○: Check or Clean ◊: Replace ●: Contact your authorized Yanmar marine dealer or distributor
System Item Periodic Maintenance Interval
Daily Every 50
hours or
monthly
which-
ever
comes
first
Every
250
hours or
one year
which-
ever
comes
first
Every
500
hours or
2 years
which-
ever
comes
first
Every
1000
hours or
4 years
which-
ever
comes
first
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
*
●
*
Lubricating
System
Check the
lube oil level
Engine ○
Marine
Gear
○
Replace the
lube oil
Engine ◊
Initial 50
◊
Marine
Gear
◊
Initial 50
◊
Replace the
oil filter
element
Engine ◊
Initial 50
◊
Marine
Gear
(if
equipped)
◊
Initial 50
◊
Cooling
System
Seawater outlet ○
During
Oper-
ation
Check coolant level ○
Check or replace the
seawater pump impeller
○ ◊
Replace coolant Every year. When Long Life Coolant is used, replace every two
years. See Engine Coolant Specifications on page 36.
Clean and check the
seawater passages
●
PERIODIC MAINTENANCE
58 JH4 Series Operation Manual