YANMAR Maintenance Schedules

Find your engine below to see its maintenance intervals. Pick a series from the list or type a model into the filter.

These schedules are a guideline. Your operation manual governs. About these schedules

Current lineup

Engines currently in the YANMAR Marine lineup.

YM Series — 2YM15 · 3YM20 · 3YM30AE

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

YM Series — periodic maintenance schedule
System Item Periodic maintenance interval
Before starting Initial 50 hrs 50 hrsor monthly 100 hrsor six months 150 hrsor one year 250 hrsor one year 1000 hrsor 4 years
Whole Visual inspection of engine exterior ○
Fuel system Check the fuel level and refill if necessary ○
Drain water and sediment from the fuel tank ○ ○
Drain the fuel / water separator ○
Replace the fuel filter element ◇
Check the fuel injection timing ●
Check the fuel injector spray pattern * ●*
Lubricating system Check the engine oil level Engine ○
Check the engine oil level Marine gear ○
Replace the engine oil Engine ◇ ◇
Replace the engine oil Marine gear ◇ ◇
Replace the engine oil Sail drive ◇
Replace the oil filter element Engine ◇ ◇
Cooling system Seawater outlet ○during operation
Check coolant level ○
Check or replace the seawater pump impeller ○ ◇
Replace coolant Every year. When Long Life Coolant (LLC) is used, replace every two years.
Clean and check the seawater passages ●
Air intake and exhaust system Clean the intake silencer (air cleaner) element ○
Clean or replace the exhaust / water mixing elbow ○
Clean the breather pipe ○
Check the exhaust gas condition ○during operation
Check diaphragm assembly ●
Electrical system Check the alarm and indicators ○
Check the electrolyte level in the battery ○
Adjust the tension of the alternator V-ribbed belt or replace V-ribbed belt ○ ○ ◇
Check the wiring connectors ○
Engine cylinder head and block Check for leakage of fuel, engine oil and engine coolant ○after starting
Tighten all major nuts and bolts ●
Adjust intake / exhaust valve clearance ○ ●
Miscellaneous items Check the remote control cables ○ ○ ●
Adjust the propeller shaft alignment ○ ●

* For EPA requirements, see Inspection and Maintenance of Emission-Related Parts, p. 56 of the operation manual.

These procedures are considered normal maintenance and are performed at the owner’s expense.

EPA emission-related parts (p. 56): clean fuel injection nozzle at 1500 hrs; check nozzle pressure and spray pattern, injection pump adjustment, turbocharger adjustment (if equipped) and the ECU with its sensors and actuators at 3000 hrs.

Source: YM Series Operation Manual — p. 54–56

JH‑CR Series — 3JH40 · 4JH45 · 4JH57 · 4JH80 · 4JH110

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

JH-CR Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrsor monthly 250 hrsor 1 year 500 hrsor 2 years 1000 hrsor 4 years
Whole Visual inspection of engine exterior ○
Fuel system Check the fuel level and refill if necessary ○
Drain water and sediment from fuel tank ○initial 50 ○
Drain the fuel/water separator ○
Replace the fuel filter element ◇
Lubricating system Check the lube oil level Engine ○
Check the lube oil level Marine gear ○
Replace the lube oil Engine ◇initial 50 ◇
Replace the lube oil Marine gear ◇initial 50 ◇
Replace the oil filter element Engine ◇initial 50 ◇
Replace the oil filter element Marine gear (if equipped) ◇initial 50 ◇
Cooling system Seawater outlet ○during operation
Check coolant level ○
Check or replace the seawater pump impeller ○ ◇
Replace coolant Every year. When Long Life Coolant is used, replace every 2 years.
Clean and check the seawater passages ●
Air intake and exhaust system Clean intake silencer (air cleaner) element ○
Clean or replace the exhaust/water mixing elbow ○ ◇
Wash the turbocharger blower — 4JH80 / 4JH110 only ●
Check diaphragm assembly — 3JH40 / 4JH45 / 4JH57 only ●
Electrical system Check the alarm and indicators ○
Check the electrolyte level in the battery ○
Adjust the tension of the alternator V-ribbed belt, or replace V-ribbed belt ○initial 50 ○ ◇
Check the wiring connectors ○
Engine cylinder head and block Check for leakage of fuel, engine oil and engine coolant ○after starting
Tighten all major nuts and bolts ●
Adjust intake/exhaust valve clearance ●initial 50 ●
Miscellaneous items Check the remote control cable operation ○initial 50 ●
Adjust the propeller shaft alignment ●initial 50 ●
Replace rubberized hoses (fuel and water) Replace every 2 years.

These procedures are considered normal maintenance and are performed at the owner’s expense.

EPA emission-related parts (p. 136): clean fuel injectors at 1500 hrs; check injectors, turbocharger adjustment and the ECU with its sensors and actuators at 3000 hrs.

Source: JH Series Operation Manual — p. 134–135

4LV Series — 4LV150 · 4LV170 · 4LV195 · 4LV230 · 4LV250

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

4LV Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrsor monthly 250 hrsor 1 year 500 hrsor 2 years 750 hrsor 4 years
Whole Visual inspection of engine exterior ○
Fuel system Check the fuel level and refill if necessary ○
Drain water and sediment from fuel tank ○initial 50 ○
Drain the fuel/water separator ○
Replace the fuel filter element ◇
Lubricating system (engine) Check the lube oil level ○
Replace the lube oil ◇initial 50 ◇
Replace the oil filter element ◇initial 50 ◇
Lubricating system (marine gear) Check the lube oil level ○
Replace the lube oil ◇initial 50 ◇
Cleaning the marine gear oil strainer ◇initial 50 ◇
Stern drive system Check the stern drive oil ○ Refer to the stern drive system operation manual
Check power steering oil ○ Refer to the stern drive system operation manual
Check power trim oil ○ Refer to the stern drive system operation manual
Cooling system Seawater outlet ○during operation
Check coolant level ○
Check or replace the seawater pump impeller ○ ◇
Replace coolant Every year. When Long Life Coolant is used, replace every 2 years.
Clean and check the seawater passages ●
Clean and check the freshwater passages ●
Replace zinc anode ◇
Air intake and exhaust system Clean intake silencer (air cleaner) element ○
Clean or replace the exhaust/water mixing elbow ○ ◇
Wash the turbocharger blower ●
Replace the lagging of turbocharger — 4LV150 / 4LV170 / 4LV195 only ●
Electrical system Check the alarm and indicators ○
Check the electrolyte level in the battery ○
Check the belt damage ○
Check the wiring connectors ○
Engine cylinder head and block Check for leakage of fuel, engine oil and engine coolant ○after starting
Miscellaneous items Check the remote control cable operation ○initial 50 ●
Adjust the propeller shaft alignment ●initial 50 ●
Replace rubberized hoses (fuel and water) Replace every 2 years.
Replace the chain tensioner slippers, chain vibration dampers and chain guide ● At 8 years or 2000 hours, whichever comes first
Replace the front crank pulley (rubber damper) ● At 8 years or 2000 hours, whichever comes first

These procedures are considered normal maintenance and are performed at the owner’s expense.

Stern drive oil, power steering and power trim: refer to the stern drive system operation manual.

Source: 4LV Series Operation Manual — p. 161–162

4LV‑C Series — 4LV150(Z)C · 4LV170(Z)C · 4LV195(Z)C · 4LV230(Z)C

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

4LV-C Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrs 250 hrs 500 hrs 1000 hrsor 1 year
Whole Visual inspection of engine exterior ○
Fuel system Check the fuel level and refill if necessary ○
Drain water and sediment from fuel tank ○initial 50 ○
Drain the fuel/water separator ○
Replace the fuel filter element ◇
Lubricating system (engine) Check the lube oil level ○
Replace the lube oil ◇initial 50 ◇
Replace the oil filter element ◇initial 50 ◇
Lubricating system (marine gear) Check the lube oil level ○
Replace the lube oil ◇initial 50 ◇
Cleaning the marine gear oil strainer ◇initial 50 ◇
Stern drive system Check the stern drive oil ○ Refer to the stern drive system operation manual
Check power steering oil ○ Refer to the stern drive system operation manual
Check power trim oil ○ Refer to the stern drive system operation manual
Cooling system Seawater outlet ○during operation
Check coolant level ○
Check or replace the seawater pump impeller ○ ◇
Replace coolant Every year. When Long Life Coolant is used, replace every 2 years.
Clean and check the seawater passages ●
Clean and check the freshwater passages ●
Replace zinc anode ◇
Air intake and exhaust system Clean intake silencer (air cleaner) element ○
Clean or replace the exhaust/water mixing elbow ○ ◇replace every 2 years
Wash the turbocharger blower ●
Replace the lagging of turbocharger — 4LV150(Z)C / 4LV170(Z)C / 4LV195(Z)C only ●
Electrical system Check the alarm and indicators ○
Check the electrolyte level in the battery ○
Check the belt damage ○
Check the wiring connectors ○
Engine cylinder head and block Check for leakage of fuel, engine oil and engine coolant ○after starting
Miscellaneous items Check the remote control cable operation ○initial 50 ●
Adjust the propeller shaft alignment ●initial 50 ●
Replace rubberized hoses (fuel and water) Replace every 2 years.
Replace the chain tensioner slippers, chain vibration dampers and chain guide ● Every 2 years or 2000 hours, whichever comes first
Replace the front crank pulley (rubber damper) ● Every 2 years or 2000 hours, whichever comes first

These procedures are considered normal maintenance and are performed at the owner’s expense.

EPA emission-related parts (p. 163): clean fuel injectors at 1500 hrs. Check injectors, turbocharger adjustment and the ECU with its sensors and actuators at 3000 hrs on 4LV150(Z)C / 4LV170(Z)C, and 4500 hrs on 4LV195(Z)C / 4LV230(Z)C.

Differs from the 4LV schedule on the chain tensioner and crank pulley intervals — 2 years here against 8 years there. Match the schedule to the model on your nameplate.

Source: 4LV Series Operation Manual (common rail edition) — p. 161–163

8LV Series — 8LV320 · 8LV350 · 8LV370

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

8LV Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrsor monthly 250 hrsor one year 500 hrsor two years 750 hrsor four years
Whole Visual inspection of engine exterior ○
Fuel system Check fuel level and refill if necessary ○
Drain water and sediment from fuel tank ○initial 50 ○
Drain fuel filter/water separator ○
Replace fuel filter element ◇
Lubricating system Check engine oil level Engine ○
Check engine oil level Marine gear ○
Replace engine oil Engine ◇initial 50 ◇
Replace engine oil Marine gear (if equipped) ◇initial 50 ◇
Replace oil filter element Engine ◇initial 50 ◇
Replace oil filter element Marine gear (if equipped) ◇initial 50 ◇
Cooling system Seawater outlet ○during operation
Check coolant level ○
Check or replace seawater pump impeller ○ ◇
Replace coolant Every year
Clean and check seawater passages ●
Replace zinc anode ◇
Air intake and exhaust system Clean intake air filter ○
Clean or replace exhaust/water mixing elbow ○ ◇
Wash the turbo-charger blower ●
Replace the lagging of turbo-charger ●
Electrical system Check alarm and indicators ○
Check electrolyte level in the battery ○
Damage of belt ○
Check wiring connectors ○
Engine cylinder head and block Check for leakage of fuel, engine oil and engine coolant ○after starting
Miscellaneous items Adjust the propeller shaft alignment ●initial 50 ●
Replace rubber hoses (fuel and water) ◇

These procedures are considered normal maintenance and are performed at the owner’s expense.

YANMAR recommends that the items above be performed at an authorized YANMAR dealer or distributor.

Source: 8LV Series Operation Manual — p. 117–118

8LV‑C Series — 8LV320C · 8LV350C · 8LV320ZC · 8LV350ZC

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

8LV-C Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrs 250 hrs 500 hrs 1000 hrsor one year
Whole Visual inspection of engine exterior ○
Fuel system Check fuel level and refill if necessary ○
Drain water and sediment from fuel tank ○initial 50 ○
Drain fuel filter/water separator ○
Replace fuel filter element ◇
Lubricating system Check engine oil level Engine ○
Check engine oil level Marine gear ○
Replace engine oil Engine ◇initial 50 ◇
Replace engine oil Marine gear (if equipped) ◇initial 50 ◇
Replace oil filter element Engine ◇initial 50 ◇
Replace oil filter element Marine gear (if equipped) ◇initial 50 ◇
Cooling system Seawater outlet ○during operation
Check coolant level ○
Check or replace seawater pump impeller ○ ◇
Replace coolant Every year
Clean and check seawater passages ●
Replace zinc anode ◇
Air intake and exhaust system Clean intake air filter ○
Clean or replace exhaust/water mixing elbow ○ ◇replace every 2 years
Wash the turbo-charger blower ●
Replace the lagging of turbo-charger ●
Electrical system Check alarm and indicators ○
Check electrolyte level in the battery ○
Damage of belt ○
Check wiring connectors ○
Engine cylinder head and block Check for leakage of fuel, engine oil and engine coolant ○after starting
Miscellaneous items Adjust the propeller shaft alignment ●initial 50 ●
Replace rubber hoses (fuel and water) Replace every 2 years

These procedures are considered normal maintenance and are performed at the owner’s expense.

EPA emission-related parts (p. 118): clean fuel injectors at 1500 hrs; check injectors, turbo-charger adjustment and the ECU with its sensors and actuators at 4500 hrs.

Source: 8LV Series Operation Manual (common rail edition) — p. 117–118

6LY‑CR Series — 6LY400 · 6LY440

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

6LY-CR Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrsor monthly 250 hrsor 1 year 500 hrsor 2 years 1000 hrsor 4 years 2000 hrsor 8 years
Whole Visual inspection of engine exterior ○
Fuel system Check the fuel level and refill if necessary ○
Drain water and sediment from fuel tank ○initial 50 ○
Drain the fuel/water separator (pre filter and main filter) ○
Replace the fuel filter element ◇
Lubricating system Check the lube oil level ○
Replace the lube oil ◇initial 50 ◇
Replace the oil filter element ◇initial 50 ◇
Cleaning the engine oil cooler ●
Cooling system (seawater) Seawater outlet ○during operation
Check or replace the seawater pump impeller ○ ●
Check or replace the zinc anodes ◇
Check and clean the seawater passage ○ ●
Cooling system (coolant) Check coolant level ○
Replace coolant Every year. When Long Life Coolant is used, replace every 2 years.
Check and clean the coolant passage ●
Air intake and exhaust system Clean intake silencer (air cleaner) element ○
Clean or replace the exhaust/water mixing elbow ○
Wash the turbocharger blower ●
Electrical system Check the alarm and indicators ○
Check the electrolyte level in the battery ○
Adjust the tension of the alternator V-belt or replace V-belt ○ ◇
Check the wiring connectors ○
Engine cylinder head and block Check for leakage of fuel, engine oil and engine coolant ○after starting
Adjust intake/exhaust valve clearance ●initial 250 ●
Marine gear Check the lube oil level Refer to the marine gear operation manual.
Replace the lube oil Refer to the marine gear operation manual.
Clean the oil strainer Refer to the marine gear operation manual.
Miscellaneous items Replace rubberized hoses (fuel and water) Replace every 2 years.

These procedures are considered normal maintenance and are performed at the owner’s expense.

EPA emission-related parts (p. 139): clean fuel injectors at 1500 hrs; check injectors, turbocharger adjustment and the ECU with its sensors and actuators at 4500 hrs.

Source: 6LY Series Operation Manual — p. 137–139

6LF Series — 6LF485 · 6LF530 · 6LF550

○ Perform this item at the marked interval

6LF Series — periodic maintenance schedule
Item Periodic maintenance interval
Daily 150 hrsor monthly 300 hrsor 1 year 600 hrsor 1 year 1000 hrsor 2 years 1200 hrsor 2 years 2400 hrsor 4 years 3000 hrsor 5 years
Engine lubricant oil level check ○
Engine coolant level check ○
Drain the water from the pre-filters / filters
Check integrity of the wiring, connectors, positive and negative poles of the power supply system and check their fastening ○
Check the level of the electrolyte solution and clean the battery poles (positive – negative) ○
Check the engine mount fastening torques ○
Check the alignment of the engine with the propeller shaft ○
Check the condition of the air filter. Clean and replace if necessary ○
Check anode wear; replace *4 if necessary ○
Check the condition of the oil vapour recirculation filter; replace the filter if necessary ○
Engine lubricant oil replacement *2 ○
Replace the engine oil filter *2 ○
Check the condition of the sea strainer at the seawater pump inlet. Clean if necessary ○
Check the state of wear of the seawater pump impeller. Replace if necessary ○
Fault memory reading via diagnostics tool ○
Check the sections of the seawater cooling circuit pipes and clean if necessary ○
Check seawater / engine oil heat exchanger, seawater / engine coolant heat exchanger and intercooler heat exchanger (air – seawater). Clean if necessary *5 ○
Turbocharger visual inspection ○
Fuel pre-filter replacement *1 ○
Fuel filter replacement *1 ○
Check auxiliary belt (V-belt) — alternator and engine cooling water pump ○
Check for signs of condensation inside the fuel tank. Clean if necessary ○
Change air filter ○
Replace engine oil vapour filter ○
Replace the seawater pump impeller ○or 5 years
Coolant replacement *3 ○
Replace auxiliary belt (V-belt) — alternator and engine cooling water pump ○
Check integrity of damper pulley mounted on the crankshaft (front side) 2400 hours or 5 years, whichever comes first
Check valve clearance ○

YANMAR publishes this schedule without a symbol legend or system grouping: each item is listed flat, with a mark in the column at which it is performed.

*1 Fuel compliant with EN 590 (sulphur content less than 10 ppm) and/or ASTM D975 (sulphur content less than 15 ppm).

*2 Minimum specification of engine oil: ACEA E7 and/or API CI-4. Viscosity: see the table on p. 63 of the manual.

*3 Engine coolant standard solution: organic base compliant with ASTM D6210 Type 1-FF. Concentrated products must be mixed 50% with water.

*4 The anode must be replaced if corrosion has affected more than 50% of the volume of zinc.

*5 Seawater / comburent air heat exchanger: clean both the air and water sections. Seawater / engine coolant exchanger: clean the seawater section. If a seawater / oil exchanger is present, clean the seawater section.

YANMAR’s table shows no interval mark against “Drain the water from the pre-filters / filters”.

Source: 6LF Series Operation Manual — p. 41–42

6LT Series — 6LT500 · 6LT580 · 6LT640

○ Perform this item at the marked interval

6LT Series — periodic maintenance schedule
Item Periodic maintenance interval
Daily 150 hrsor monthly 300 hrsor 1 year 600 hrsor 1 year 900 hrsor 1 year 1200 hrsor 2 years 2400 hrsor 4 years 3000 hrsor 5 years
Engine oil level check ○
Engine coolant level check ○
Drain the water from the pre-filter ○
Check the level of the electrolyte solution and clean the battery poles ○or every 6 months
Check the condition of the air filter. Clean and replace if necessary ○ Replace
Check zinc anode wear; replace (4) if necessary. In warm and very salty waters such as the Mediterranean, check anodes every 6 months ○
Check the condition of the oil vapour recirculation filter; replace the filter if necessary ○ Replace at 600 h
Engine oil replacement (2) ○
Replace the engine oil filter (2) ○
Check the condition of the filter at the seawater pump inlet. Clean if necessary ○
Fault memory reading via diagnostics tool ○
Check the state of wear of the seawater pump rotor. Replace if necessary ○
Check the sections of the seawater cooling circuit pipes and clean if necessary ○
Check seawater / engine oil heat exchanger, seawater / engine coolant heat exchanger and intercooler heat exchanger (air – seawater). Clean if necessary (5) ○
Turbocharger visual inspection ○
Fuel pre-filter replacement (1) Replace at 600 h
Fuel filter replacement (1) Replace at 600 h
Check auxiliary belt (V belt) — alternator and engine cooling water pump ○ Replace every 3 years
Check for signs of condensation inside the fuel tank. Clean if necessary ○
Coolant replacement (3) ○
Check integrity of damper pulley mounted on the crankshaft (front side) ○
Check valve clearance ○
Check the condition of exhaust duct(s) ○
Check the oil level in the gearbox ○
Change the oil in the gearbox Refer to the marine gear operation manual

YANMAR publishes this schedule without a symbol legend or system grouping: each item is listed flat, with a mark in the column at which it is performed.

(1) Fuel compliant with EN 590 (sulfur content less than 10 ppm) and/or ASTM D975 (sulfur content less than 15 ppm).

(2) Minimum specification of engine oil: ACEA E7 and/or API CI-4. Viscosity: see the table on p. 28 of the manual.

(3) Engine coolant standard solution: organic base compliant with ASTM D6210 Type 1-FF. Concentrated products must be mixed 50% with water. Original YANMAR products are recommended.

(4) The anode must be replaced if corrosion has affected more than 50% of the volume of zinc.

(5) Seawater / combustion air heat exchanger: clean both the air and water sections. Seawater / engine coolant exchanger: clean the seawater section. Seawater / oil exchanger: clean the seawater section.

Source: 6LT Series Operation Manual — p. 43–44

Discontinued models

Parts and service still available through Mastry.

GM Engine — 1GM10

○ Check ◉ Replace ● Consult local dealer

GM Engine — periodic maintenance schedule
System Item Periodic maintenance interval
Before starting After 50 hrsor one month 150 hrs 300 hrs 600 hrsor 1 year
Fuel system * Check the fuel level, and refill ○
Drain the fuel tank ○first ○
Drain the fuel filter ○
Replace the fuel filter ◉
Check the injection timing ●
Check the injection spray condition ●
Lubricating system Check the lube oil level Crankcase ○
Check the lube oil level Marine gear ○
Replace the lube oil Crankcase ◉first ◉
Replace the lube oil Marine gear ◉first ◉
Check the oil pressure warning lamp function ○
Replace the lube oil filter ◉first ◉
Cooling system Seawater outlet ○during operation
Check cooling water level ○
Adjust the tension of cooling water pump driving belt ○first ○
Check the impeller of the cooling water pump (seawater pump) ○
Replace the fresh water cooling Every year
Check and replace the anticorrosion zinc ◉
Air intake and exhaust system Clean the element of the air intake silencer ○
Clean the exhaust/water mixing elbow ○
Clean the breather pipe ○
Check the exhaust gas condition ○during operation
Electrical system Check the charge lamp function ○
Check the electrolyte level in the battery ○ ○
Adjust the tension of the alternator driving belt ○first ○
Check the wiring connectors ○
Cylinder head, etc. Check for leakage of water and oil ○after starting
Retighten all major nuts and bolts ●
Adjust intake/exhaust valve clearance ○first ●
Remote control system, etc. Check the remote control operation ○first ●
Adjust the propeller shaft alignment ○first ●

* For EPA requirements, see also section 4.4 of the operation manual.

Source: GM Series Operation Manual — §4 Maintenance & Inspection, p. 36

YM Series, earlier manual — 3YM30

○ Check or clean ◎ Replace ● Consult your authorized YANMAR Marine dealer or distributor

3YM30 — periodic maintenance schedule
System Item Periodic maintenance interval
Before starting Initial 50 hrs 50 hrsor monthly 100 hrsor six months 150 hrsor one year 250 hrsor one year 1000 hrsor 4 years
Fuel system Check the fuel level, and refill ○
Drain the fuel tank ○ ○
Drain the fuel/water separator ○
Replace the fuel filter ◎
Check the injection timing ●
Check the injection spray condition ●*
Lubricating system Check the lubricating oil level Crankcase ○
Check the lubricating oil level Marine gear ○
Replace the lubricating oil Crankcase ◎ ◎
Replace the lubricating oil Marine gear ◎ ◎ ◎
Replace the lubricating oil Sail drive ◎
Replace the engine lubricating oil filter ◎ ◎
Cooling system Seawater outlet ○during operation
Check cooling water level ○
Check the impeller of the cooling water pump (seawater pump) ○ ◎
Replace the fresh water coolant Every year. When long life coolant of a specified type is used (see p. 24 of the operation manual), a replacement period of two years can be obtained.
Clean and check the water passages ●
Air intake and exhaust system Clean the element of the air intake silencer ○
Clean the exhaust/water mixing elbow ○
Clean the breather pipe ○
Check the exhaust gas condition ○during operation
Diaphragm assembly inspection ●
Electrical system Check the alarm lamps and devices ○
Check the electrolyte level in the battery ○
Adjust the tension of the alternator driving belt ○ ○ ◎
Check the wiring connectors ○
Cylinder head, etc. Check for leakage of water and oil ○after starting
Retighten all major nuts and bolts ●
Adjust intake/exhaust valve clearance ○ ●
Remote control system, etc. Check/adjust the remote control operation ○ ○ ●
Adjust the propeller shaft alignment ○first ●

Where an interval gives both hours and a calendar period, whichever comes first.

* For EPA requirements, see also §4.4 of the operation manual.

Source: 3YM30 Operation Manual — §4, p. 38

4JH3 Series — 4JH3‑TE · 4JH3‑TCE · 4JH3‑HTE · 4JH3‑DTE

○ Check or clean ◎ Replace ● Consult your authorized YANMAR Marine dealer or distributor

4JH3 Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrs 250 hrs1 year 500 hrs2 years 1000 hrs4 years
Fuel oil Check and supply fuel oil to the tank ○
Drain the fuel tank ○
Drain the fuel filter ○
Replace the fuel filter element ◎
Engine lube oil Check the quantity of lube oil ○
Replace the lube oil ◎1st time ◎2nd time and after
Replace the lube oil filter element ◎1st time ◎2nd time and after
Clean the engine oil cooler ●
Marine gear lube oil Check the quantity of lube oil ○
Replace the lube oil ◎1st time ◎2nd time ◎3rd time and after
Wash the lube oil filter ○1st time ○2nd time ○3rd time and after
Clean the oil cooler ●
Fresh cooling water system Check and supply the cooling water tank ○
Replace the fresh cooling water ◎
Clean and check the cooling water passage ●
Seawater cooling system Check the seawater outlet and discharge ○
Check and replace the seawater pump impeller ●
Clean and check the seawater passage ●
Piping Check and replace the fuel oil pipe and cooling water pipe ○ ●
Replace the mixing elbow ○ ●
Electrical equipment Check the alarm lamps and devices ○
Check and supply electrolyte in the battery ○
Belt Adjust the V-belt tension ○
Remote control handle Check the remote control operation, and grease ○
Adjust the remote control cable ○
Intake and exhaust system Wash the turbocharger blower ○
Adjust the intake and exhaust valve clearance ●
Lap the intake and exhaust valves ●
Fuel injection Check and adjust the fuel injection pressure and atomizing condition ●
Check and adjust the fuel injection timing ●

Not interchangeable with the 4JH4 or JH-CR schedules.

Source: 4JH3 Series Operation Manual (YANMAR 49961-202851, covering 4JH3-TE, 4JH3-TCE, 4JH3-HTE and 4JH3-DTE) — §5.1, p. 36

JH Series (pre-common rail) — 4JH‑TE · 4JH‑HTE and related mechanically injected JH engines

○ Check ◉ Replace ● Consult local dealer

JH Series (pre-common rail) — periodic maintenance schedule
System Item Periodic maintenance interval
Before starting After 50 hrsor one month 250 hrs1 year 500 hrs2 years 1000 hrs4 years
Fuel system Check the fuel level, and refill ○
Drain the fuel tank ○first ○
Drain the fuel filter ○
Replace the fuel filter ◉
Check the injection timing ●
Check the injection spray condition ○
Lubricating system Check the lube oil level Crankcase ○
Check the lube oil level Marine gear ○
Replace the lube oil Crankcase ◉first ◉
Replace the lube oil Marine gear ◉first ◉
Replace the engine lube oil filter Engine ◉first ◉
Wash the lube oil filter Marine gear ○first ○ ○
Clean the engine oil cooler Engine ●
Clean the oil cooler Marine gear ●
Cooling system Seawater outlet ○during operation
Check cooling water level ○
Check the impeller of the cooling water pump (seawater pump) ○ ◉
Replace the fresh water cooling Every year
Clean & check the water passages ●
Air intake and exhaust system Clean the element of the air intake silencer ○
Clean the exhaust/water mixing elbow ○
Clean the breather pipe ○
Check the exhaust gas condition ○during operation
Wash turbocharger blower ○
Electrical system Check the alarm lamps & devices ○
Check the electrolyte level in the battery ○
Adjust the tension of the alternator driving belt ○first ○ ◉
Check the wiring connectors ○
Cylinder head, etc. Check for leakage of water and oil ○after starting
Retighten all major nuts and bolts ●
Adjust intake/exhaust valve clearance ○first ●
Remote control system, etc. Check / adjust the remote control operation ○ ○
Adjust the propeller shaft alignment ○first ○

Not interchangeable with the JH-CR schedule. The injection-timing and spray-condition items below do not exist on a common rail JH engine.

Source: JH Series Operation Manual — §4 Maintenance & Inspection, p. 36

LH Series — 4LHA‑HTP · 4LHA‑DTP · 4LHA‑STP

○ Check ◎ Replace ● Consult local dealer

LH Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrs 250 hrs1 yr 500 hrs2 yrs 1000 hrs4 yrs 2000 hrs
Fuel oil Check & supply of oil to the tank ○
Drain the fuel tank ○
Drain the fuel filter and water separator ○
Replace the fuel filter element ◎
Lube oil Check the quantity of lube oil ○
Replace the lube oil ◎first ◎
Replace the lube oil filter element ◎first ◎
Wash engine oil cooler ●
Drive oil Check the quantity of drive oil ○
Replace drive oil Refer to operation manual of marine drive.
Check power trim oil ○
Check power steering oil ○
Marine gear oil Marine gear oil For information on marine gears, refer to the maker’s manual.
Fresh cooling water system Check & supply of cooling water tank ○
Replace the fresh cooling water ◎
Clean & check the cooling water passage ●
Seawater cooling water system Check the seawater outlet and discharge ○
Check & replace the impeller of seawater pump ○ ●
Check & replace the anti corrosive zincs ◎
Clean & check the seawater passage ●
Piping Check fuel oil pipe, cooling water pipe ○
Check mixing elbow ○
Electrical equipment Check the alarm lamps & devices ○
Check supply electrolyte in battery ○
Belt Check V-belt ○
Remote control handle Check the remote control operation & grease ○
Adjusting the remote control cable ○
Intake and exhaust system Wash turbocharger blower ○
Adjust the intake and exhaust valve clearance ●first ●
Lapping the intake / exhaust valve ●
Fuel injection Check & adjust the fuel injection pressure & atomizing condition ●first ●
Check & adjust the fuel injection timing ●

Refer to the accompanying operation manuals for periodic inspection and maintenance of the marine drive and remote control system.

Source: 4LHA Series Operation Manual — §5.1 List of Periodic Inspections, p. 43

LP Series — 6LPA‑STP2 · 6LPA‑STZP2

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

LP Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrsor monthly 125 hrsor 6 months 250 hrsor 1 year 500 hrsor 2 years 1000 hrsor 4 years 1250 hrsor 5 years
Whole Visual inspection of engine exterior ○
Fuel system Check the fuel level and refill if necessary ○
Drain water and sediment from fuel tank ○
Drain the fuel/water separator ○
Replace the fuel filter element ◇initial 50 ◇
Check the fuel injection timing ●*
Check the fuel injector pressure and nozzle spray pattern * ●initial 250 ●*
Lubricating system Check the engine oil level ○
Change the engine oil ◇initial 50 ◇
Replace the engine oil filter element ◇initial 50 ◇
Wash the engine oil cooler ●
Marine drive system Check the marine drive oil ○
Check power steering oil ○
Check power trim oil ○
Check drive oil ○
Fresh water cooling system Check coolant level ○
Change coolant ◇
Clean and check the cooling water passage ●
Clean the cooling water system ●
Seawater cooling system Check seawater outlet discharge ○during operation
Check or replace the seawater pump impeller ●
Check or replace the zinc anodes ◇
Check and clean the seawater passage ●
Piping Clean or replace the exhaust/water mixing elbow ●
Check or replace fuel line and rubber hoses ○ ●
Electrical system Check the alarm and indicators ○
Check the electrolyte level in the battery ○
Adjust the tension of the alternator V-belt or replace V-belt ○ ●
Remote control handle Check and lubricate the remote control cable operation ○
Adjust the remote control cable ○
Intake and exhaust system Wash turbocharger blower ●
Clean air cleaner ○
Adjust the intake and exhaust valve clearance ●initial 250 ●
Lap the intake and exhaust valves ●
Miscellaneous Check and adjust the power steering oil pump belt (6LPA-STZP2) ○
Replace the timing belt ●
Replace the front rubber damper ●

These procedures are considered normal maintenance and are performed at the owner’s expense.

* EPA emission-related parts (p. 56): clean fuel injection nozzle at 1500 hrs; check nozzle adjustment, repair or replace the injection pump, check turbocharger adjustment and the ECU with its sensors and actuators at 3000 hrs.

Source: 6LPA Series Operation Manual — p. 52–56

BY Series — 4BY · 6BY

○ Check ◇ Replace ● Contact your authorized YANMAR marine dealer or distributor

BY Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrsor monthly 250 hrsor one year 500 hrsor 2 years
Whole Visual inspection of engine exterior ○before starting
Fuel system Check for fuel leakage ○before starting
Check the fuel level and refill if necessary ○before starting
Drain water and sediment from fuel tank ○
Drain the fuel filter / water separator if necessary ○
Replace the fuel pre-filter ◇
Replace the fuel fine filter ◇
Replace fuel filter / water separator element ◇
Check the fuel pump and fuel lines ●
Lubricating system Check the engine oil level and refill if necessary ○before starting
Change the engine oil and replace the oil filter element ◇initial 50 ◇
Cooling system — engine coolant Visual inspection of cooling system ○before starting
Check coolant level and check for leaks ○before starting
Replace coolant ◇
Cooling system — seawater circuit Visual inspection of cooling system ○before starting
Check the seawater outlet ○before starting
Check seawater pump belt for wear, replace if necessary ◇
Check seawater filter (if equipped) and inlet ○
Replace the zinc anodes * ◇
Check or replace the seawater pump impeller ●
Air intake and exhaust system Visual inspection ○before starting
Replace turbocharger heat shield ●
Check the exhaust pipe ○
Check the air intake pipes ○
Check the exhaust / water mixing elbow ●
Clean or replace the air filter element ** ○
Electrical system Check the electrolyte level in the battery (serviceable batteries only) ○
Check the wiring connectors ○before starting
Check alternator belt for wear, replace if necessary ◇
Miscellaneous items Check the alarm and indicators (if equipped) ○
Check or change power steering fluid ○ ●
Check for water or oil leakage ○before starting
Check shift cable adjustment ●initial 50 ●
Adjust the propeller shaft alignment (if equipped with marine gear) ●initial 50 ●
Check hydraulic oil cooler ●
Check and replace rubberized hoses (fuel and water) ●

* Check zinc anodes periodically. Any anode having less than 1/2 its original size remaining should be replaced — use this to establish a regular replacement interval.

** Recommendation: use washing kit BMC WA250-355.

EPA emission-related parts (p. 82): check turbocharger adjustment at 3000 hrs.

Source: BY Series Operation Manual — p. 80–82

BY2 / BY3 Series — 4BY2 · 6BY2 · 4BY3 · 6BY3

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

BY2 / BY3 Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrsor monthly 250 hrsor one year 500 hrsor 2 years 750 hrsor 4 years
Whole Visual inspection of engine exterior ○before starting
Fuel system Check for fuel leakage ○before starting
Check the fuel level and refill if necessary ○before starting
Drain water and sediment from fuel tank ○
Drain the fuel filter/water separator if necessary ○
Replace the fuel fine filter ◇
Replace fuel filter/water separator element ◇
Check the fuel pump and fuel lines ●
Lubricating system Check the engine oil level and refill if necessary ○before starting
Change the engine oil and replace the oil filter element ◇initial 50 ◇
Cooling system — engine coolant Visual inspection of cooling system ○before starting
Check coolant level and check for leaks ○before starting
Replace coolant When Long Life Coolant (LLC) is used, replace every two years.
Cooling system — seawater circuit Visual inspection of cooling system ○before starting
Check the seawater outlet ○before starting
Check seawater pump belt for wear, replace if necessary ◇
Check seawater filter (if equipped) and inlet ○
Replace the anodes * ◇
Check or replace the seawater pump impeller ● ●
Air intake and exhaust system Visual inspection ○before starting
Replace turbocharger heat shield ◇
Check the exhaust pipe ○
Check the air intake system ○
Check the exhaust/water mixing elbow ●
Replace the air filter element ●
Electrical system Check the electrolyte level in the battery (serviceable batteries only) ●
Check the wiring connectors ○before starting
Check alternator belt for wear, replace if necessary ○ ●
Miscellaneous items Check the alarm and indicators (if equipped) ○
Check or change power steering fluid ● ●
Check for water or oil leakage ○before starting
Check shift cable adjustment ●initial 50 ●
Adjust the propeller shaft alignment (if equipped with marine gear) ●initial 50 ●
Check hydraulic oil cooler ●
Check and replace rubberized hoses (fuel and water) ●
Check flexible engine mounts ○ ●

* Check anodes periodically. Any anode having less than half its original size remaining should be replaced — use this to establish a regular replacement interval.

These procedures are considered normal maintenance and are performed at the owner’s expense.

The BY2 and BY3 series share this schedule.

Source: BY3 Series Operation Manual — p. 47–50

LY Series — 6LY2A‑UTP · 6LY2A‑STP

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

LY Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrsor monthly 250 hrsor 1 year 500 hrsor 2 years 1000 hrsor 4 years 2000 hrsor 8 years
Whole Visual inspection of engine exterior ○
Fuel system Check the fuel level and refill if necessary ○
Drain water and sediment from fuel tank ○initial 50 ○
Drain the fuel / water separator ○
Replace the fuel filter element ◇
Check the fuel injection timing ●
Check the fuel injector spray pattern ●initial 250 ●
Lubricating system Check the lube oil level ○
Replace the lube oil ◇initial 50 ◇
Replace the oil filter element ◇initial 50 ◇
Cleaning the engine oil cooler ●
Cooling system (seawater) Seawater outlet ○during operation
Check or replace the seawater pump impeller ○ ●
Check or replace the zinc anodes ◇
Check and clean the seawater passage ○ ●
Cooling system (coolant) Check coolant level ○
Replace coolant Every year. When Long Life Coolant is used, replace every 2 years.
Check and clean the coolant passage ●
Air intake and exhaust system Clean intake silencer (air cleaner) element ○
Clean or replace the exhaust / water mixing elbow ○
Wash the turbocharger blower ●
Electrical system Check the alarm and indicators ○
Check the electrolyte level in the battery ○
Adjust the tension of the alternator V belt or replace V belt ○
Check the wiring connectors ○
Engine cylinder head and block Check for leakage of fuel, engine oil and engine coolant ○after starting
Adjust intake / exhaust valve clearance ●initial 250 ●
Marine gear Check the lube oil level Refer to the marine gear operation manual.
Replace the lube oil Refer to the marine gear operation manual.
Clean the oil strainer Refer to the marine gear operation manual.
Miscellaneous items Check the remote control cable operation ○ ○
Replace rubberized hoses (fuel and water) Replace every 2 years.

These procedures are considered normal maintenance and are performed at the owner’s expense.

Source: 6LY2A Series Operation Manual — p. 54–55

6LY3 Series — 6LY3‑ETP · 6LY3‑STP · 6LY3‑UTP

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

6LY3 Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrsor monthly 250 hrsor one year 500 hrsor two years 1000 hrsor four years 2000 hrsor eight years
Whole Visual inspection of engine exterior ○
Fuel system Check the fuel level and refill if necessary ○
Drain the fuel tank ○
Drain the fuel filter and fuel/water separator ○
Replace the fuel filter element ◇1st time ◇
Check the fuel injector spray pattern ●1st time ●
Overhaul and check fuel feed pump ●
Replace rubber fuel hoses Replace every 2 years or every 2000 hours, whichever comes first.
Lubricating system Check the engine oil level Crankcase ○
Replace the engine oil Crankcase ◇1st time ◇
Replace the oil filter element ◇1st time ◇
Clean engine oil cooler ●
Cooling system Seawater outlet ○during operation
Check coolant level ○
Check the seawater pump impeller ○ ◇
Replace the engine coolant Every year. When Long Life Coolant (LLC) is used, replace every two years.
Clean and check the seawater passages ●
Clean seawater and engine cooling system ●
Replace zinc anode ◇
Air intake and exhaust system Clean the air intake silencer ○
Clean the exhaust/water mixing elbow ○ ◇
Clean the turbocharger blower ●
Flush air cooler ●
Electrical system Check the alarm indicators ○
Check the electrolyte level in the battery ○
Adjust the tension of the alternator V-belt or replace V-belt ○ ○ ◇
Check the wiring connectors ○
Engine cylinder head and block Check for leakage of fuel, engine oil and engine coolant ○after starting
Tighten all major nuts and bolts ●
Adjust intake/exhaust valve clearance ●1st time ●
Miscellaneous items Check the electronic control system operation ○ ○1st time
Adjust the propeller shaft alignment ●1st time ●
Check/replace flexible engine mounts ○ ◇

These procedures are considered normal maintenance and are performed at the owner’s expense.

Source: 6LY3 Series Operation Manual — p. 44–46

SY Series — 6SY

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

SY Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrsor one month 250 hrsor one year 500 hrsor 2 years 1000 hrsor 4 years 2000 hrsor 8 years
Whole Visual inspection of engine exterior ○
Fuel system Check the fuel level, and refill ○
Drain the fuel tank ○
Drain the fuel filter and the fuel / water separator ○initial 50
Replace the fuel filter element ◇
Check the unit injector / rocker arms * ●initial 250 ●*
Overhaul and check the fuel feed pump ●
Replace the rubber fuel hoses Replace every 2 years or every 2000 hours, whichever comes first.
Lubricating system Check the engine oil level ○
Change the engine oil ◇initial 50 ◇
Replace the engine oil filter element ◇initial 50 ◇
Replace the closed crankcase ventilation filter element ◇
Clean the centrifugal oil cleaner ○initial 50 ○
Clean the engine oil cooler ●
Cooling system Check the seawater outlet ○during operation
Check the coolant level ○
Check or replace the seawater pump impeller ○ ◇
Change the engine coolant Every year. When long life coolant is used, replace every two years.
Clean and check the seawater passages ●
Clean the seawater and engine cooling system ●
Check or replace the anodes ◇
Clean the closed cooling system (internal) ○
Air intake and exhaust system Clean or replace the air intake filter element ○
Clean the exhaust/water mixing elbow ●
Clean the turbocharger * ●*
Clean charge air cooler ●
Electrical system Check the alarm indicators ○
Check the battery charge ○
Clean the battery ○
Check battery electrolyte level ○
Adjust the tension of the alternator belt or replace belt ○initial 50 ○ ◇
Check the wiring connectors ○ ●
Engine cylinder head and block Check for leakage of fuel, engine oil and engine coolant ○after starting
Tighten all major nuts and bolts ●
Adjust the intake / exhaust valve clearance ●initial 250 ●
Miscellaneous items Check the electronic control system (EMS) operation ○ ○initial 50
Adjust the propeller shaft alignment ●initial 50 ●
Check or replace the flexible engine mounts ○ ◇

* Required to conform to U.S. EPA regulations. See EPA Requirements USA Only, p. 34 of the operation manual.

These procedures are considered normal maintenance and are performed at the owner’s expense.

Source: 6SY Operation Manual — p. 37–38

6CX Series — 6CX530

○ Check or clean ◇ Replace ● Consult your authorized YANMAR Marine dealer or distributor

6CX Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrsor monthly 250 hrsor one year 500 hrsor two years 1000 hrsor four years
Whole Visual inspection of engine exterior ○
Fuel system Check fuel level and refill if necessary ○
Drain water and sediment from fuel tank ○initial 50 ○
Drain fuel filter / water separator ○
Replace fuel filter element ◇
Replace fuel primary filter (if equipped) ◇
Check the fuel injection timing ●
Check fuel injector spray pattern * ●*
Lubricating system Check engine oil level Engine ○
Check engine oil level Marine gear ○
Replace engine oil Engine ◇initial 50 ◇
Replace engine oil Marine gear ◇initial 50 ◇
Replace oil filter element Engine ◇initial 50 ◇
Clean the oil strainer Marine gear (if equipped) ○initial 50 ○
Cooling system Seawater outlet ○during operation
Check coolant level ○
Check or replace seawater pump impeller ○ ◇
Replace coolant Every year. When Long Life Coolant is used, replace every two years.
Clean and check seawater passages ●
Replace zinc anode ◇
Air intake and exhaust system Clean intake air filter ○
Clean or replace exhaust / water mixing elbow ○ ◇
Clean turbocharger * ●
Electrical system Check alarm and indicators ○
Check electrolyte level in the battery ○
Adjust tension of the alternator belt or replace belt ○initial 50 ○ ◇
Check wiring connectors ○
Engine cylinder head and block Check for leakage of fuel, engine oil and engine coolant ○after starting
Tighten all major nuts and bolts ●
Adjust intake / exhaust valve clearance ●initial 50 ●
Miscellaneous items Adjust the propeller shaft alignment ●initial 50 ●
Replace rubberized hoses (fuel and water) Replace every 2 years or every 2000 hours, whichever comes first.

* For EPA requirements, see Inspection and Maintenance of EPA Emission-Related Parts for Non-Road and CI Marine Engines, p. 64 of the operation manual.

These procedures are considered normal maintenance and are performed at the owner’s expense.

Source: 6CX Series Operation Manual — p. 62–63

Industrial engines and generators

YANMAR industrial engines and generator sets.

L‑V Series — Air-cooled industrial — L48V and related

○ Check ◇ Replace ● Consult your authorized YANMAR industrial engine dealer or distributor

L-V Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrs 200 hrs 400 hrs 1000 hrs 1500 hrs 2000 hrs
Air intake Clean or replace air cleaner element — may need more frequent service in dusty conditions ○100 hours ◇500 hours
Cylinder head Adjust intake/exhaust valve clearance ●
Check compression ●
Electrical equipment Check battery and add water as necessary ○before operation
Check battery indicator (if equipped) and other driven machine indicators (if equipped) ○when engine is started
Emission control warranty Inspect, clean and test fuel injection nozzle ●
Inspect for serious damage or poor appearance of the muffler (DOC) — EU regulation certified L48V only ●every 3000 hours *1
Engine oil Check engine oil level and add engine oil as necessary ○before operation
Drain and refill engine oil ◇1st time ◇2nd and after
Clean, check or replace engine oil filter — replace if damaged. May need more frequent service in dusty conditions ◇1st time ○ ◇2nd and after
Check for engine oil leakage ○before and after operation
Engine speed control Check for proper operation, verify adjustment ○1st time only ○2nd and after
Exhaust system Check spark arrestor for clogging ○before operation
Fuel Check fuel tank level and add fuel as necessary ○before operation
Drain and clean fuel tank ○
Clean inlet fuel screen ○
Replace outlet fuel filter ◇
Check for fuel leakage ○before and after operation
Hoses Replace fuel system hose(s) ●or every 2 years, whichever comes first

*1 If you find any damage or dent, contact your authorized YANMAR industrial engine dealer or distributor.

This is an industrial engine schedule. It is not the marine 4LV or 8LV schedule.

Source: L-V Series Operation Manual — p. 40–41

TNM Series — 2TNM · 3TNM

○ Check ◇ Replace ● Consult your authorized YANMAR industrial engine dealer or distributor

TNM Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrs 250 hrs 500 hrs 1000 hrs 1500 hrs 2000 hrs
Cooling system Check and refill engine coolant ○
Check and clean radiator fins ○ ○
Check and adjust cooling fan V-belt ○1st time ○2nd and after
Drain, flush and refill cooling system with new coolant ◇or every 1 year, whichever comes first
Cylinder head Adjust intake/exhaust valve clearance ●
Lap intake/exhaust valve seats (if required) ●
Electrical equipment Check indicators ○
Check battery ○
Engine oil Check engine oil level ○
Drain and fill engine oil ◇1st time ◇2nd and after
Replace engine oil filter ◇
Engine speed control Check and adjust governor lever and engine speed control ○ ○
Emission control warranty Inspect, clean and test fuel injectors ●
Inspect crankcase breather system ●
Fuel Check and refill fuel tank level ○
Drain fuel tank ○
Drain fuel filter/water separator ○
Check fuel filter/water separator ○
Clean fuel filter/water separator ○
Replace fuel filter ◇
Hoses Check or replace fuel system and cooling system hoses ○ ●or every 2 years
Intake and exhaust Clean or replace air cleaner element ○ ◇
Complete engine Overall visual check daily ○

These procedures are considered normal maintenance and are performed at the owner’s expense.

Source: TNM Series Operation Manual — p. 40–41

TNV Series — 3TNV · 4TNV

○ Check ◇ Replace ● Consult your authorized YANMAR industrial engine dealer or distributor

TNV Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrs 250 hrs 500 hrs 1000 hrs 1500 hrs 2000 hrs 3000 hrs
Cooling system Check and refill engine coolant ○
Check and clean radiator fins ○
Check and adjust cooling fan V-belt ○1st time ○2nd and after
Drain, flush and refill cooling system with new coolant ◇or every 2 years, whichever comes first
Cylinder head Adjust intake/exhaust valve clearance ●
Electrical equipment Check indicators ○
Check battery ○
Engine oil Check engine oil level ○
Drain and fill engine oil ◇*1 ◇or every 1 year *2
Replace engine oil filter ◇*1 ◇or every 1 year *2
Engine speed control Check and adjust governor lever and engine speed control ○ ○
Emission control warranty Inspect, clean and test fuel injectors, if necessary ●cleaning only ●
Inspect turbocharger (blower wash as necessary) — DI engine ●
Inspect, clean and test EGR valve ●
Clean EGR lead valve — DI engine ●
Clean EGR cooler (blow out water/air passages) — DI engine ●
Inspect crankcase breather system ●
Fuel Check and refill fuel tank level ○
Drain fuel tank ○
Drain fuel filter/water separator ○
Check fuel filter/water separator ○
Clean fuel filter/water separator ○
Replace fuel filter ◇
Hoses Replace fuel system and cooling system hoses ◇or every 2 years
Intake and exhaust Clean or replace air cleaner element ○ ◇
Complete engine Overall visual check daily ○

*1 IDI model only. *2 DI model only (differs depending on the application or engine oil capacity). If the engine is equipped with a shallow type oil sump, the maintenance interval should be every 250 hours regardless of the implement.

Check the oil level daily. If it is below the lower limit of the dipstick, add new oil to keep the level between the upper and lower marks, even if the change interval has not been reached.

These procedures are considered normal maintenance and are performed at the owner’s expense.

Source: TNV Operation Manual — p. 90–91

YDG Series — YDG portable diesel generators

○ Check ◇ Replace ● Contact your authorized YANMAR dealer or distributor for these maintenance services

YDG Series — periodic maintenance schedule
System Item Periodic maintenance interval
Daily 50 hrs 200 hrs 400 hrs 1000 hrs 1500 hrs 2000 hrs
Air intake Clean or replace air cleaner element — may need more frequent service in dusty conditions ○100 hours ◇500 hours
Cylinder head Adjust intake/exhaust valve clearance ●
Check compression ●
Electrical equipment Check battery and add water as necessary ○before operation
Check battery indicator (if equipped) and other driven machine indicators (if equipped) ○when engine is started
Emission control warranty Inspect, clean and test fuel injection nozzle ●cleaning only ●every 3000 hours
Inspect for serious damage or poor appearance of the muffler (DOC) ●every 3000 hours *1
Engine oil Check engine oil level and add engine oil as necessary ○before operation
Drain and refill engine oil ◇1st time ◇2nd and after
Clean, check or replace engine oil filter — replace if damaged. May need more frequent service in dusty conditions ◇1st time ○ ◇2nd and after
Check for engine oil leakage ○before and after operation
Engine speed control Check for proper operation, verify adjustment ○1st time only ○2nd and after
Exhaust system Check spark arrestor for clogging ○before operation
Fuel Check fuel tank level and add fuel as necessary ○before operation
Drain and clean fuel tank ○
Clean inlet fuel screen ○
Replace outlet fuel filter ◇
Check for fuel leakage ○before and after operation
Hoses Replace fuel system hose(s) ●or every 2 years, whichever comes first
Generator Check brushes for wear or damage ●
Check slip rings for wear or damage ●
Check coils and Automatic Voltage Regulator (AVR) for correct operation ●
Frame Check main and sub frames for damage ●
Check engine/frame dampers for wear, damage and tightness ●
Check all fasteners for damage and tightness ●
GFCI outlet Test outlet ●

*1 If you find any damage or dent, contact your authorized YANMAR dealer or distributor.

These procedures are considered normal maintenance and are performed at the owner’s expense.

Source: YDG Operation Manual — p. 47–48

About these schedules

Daily and periodic inspection is what keeps a YANMAR engine in its best condition. The schedules below summarize YANMAR’s inspection and service items by interval for each engine series.

Inspection intervals vary with how an engine is used — application, load, the fuel and lubricating oil in it, and handling and storage conditions — and cannot be set definitively for every installation. Everything on this page should be treated only as a general standard. Schedule your own periodic inspection plan around the operating conditions of your engine, and inspect every item on it. Neglecting periodic inspection leads to engine trouble and shortens the life of the engine.

These schedules are a guideline. Your operation manual governs.

  • The operation manual for your engine is the authority. This page is a reference published by Mastry Engine Center and transcribed from YANMAR operation manuals. Where this page and the manual for your engine and serial number differ, follow the manual. If you do not have it, an authorized YANMAR dealer can supply it.
  • Items marked “consult your dealer” are dealer-level service. They call for training, tooling or measurement that is not owner-level work, and YANMAR directs that they be carried out by an authorized YANMAR dealer or distributor.
  • Emission-related and warranty work belongs with an authorized dealer. Items tied to EPA emission-related parts, and any work performed during the warranty period, should go through an authorized YANMAR dealer or distributor to keep the engine compliant and the warranty intact.
  • Drives, gears and controls are not covered here. Refer to the accompanying operation manuals for periodic inspection and maintenance of the marine drive and the remote control system.

If there is any question about an interval, a procedure, or whether an item applies to your engine, contact an authorized YANMAR dealer before working on the engine.

Items marked “consult your dealer” are dealer-level service. Mastry can point you to the nearest authorized YANMAR service center.

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