Maintenance & Inspection - Yanmar 4LHA-HTP Operation Manual

5. MAINTENANCE & INSPECTION
Conduct Periodic Inspection for Your Safety.
The functions of engine components will degenerate and engine performance will fall
according to the use of the engine. If periodic inspections are not performed, you may
encounter unexpected troubles while cruising at sea, and consumption of fuel or lube oil may
become excessive and exhaust gas and engine noise may increase. These all shorten the life
of the engine.
Daily and periodic inspection and servicing increase your safety operation.
Inspect Before Starting.
Make it a daily rule to inspect before starting.
Monitor the hour meter and conduct periodic inspections.
Keep a daily record of operation and maintenance. When the time for an inspection
approaches, study the relevant pages in the Operation Manual. Inspections should be made
after every 50, 250(or 1 yr.), 500 (or 2 yrs.), 1000(or 4 yrs.), and 2000 hours of use.
Monitor the hourmeter and conduct periodic inspections according to the procedures
described in this Operation Manual.
Use Genuine Parts.
Be sure to use genuine parts for consumable and replacement parts.
Use of other parts will reduce engine performance and shorten the life of the engine.
Servicing Tools :
Prepare servicing tools onboard to be ready for inspecting and servicing the engine and other
equipments.
Tightening Torque of Nuts & Bolts
Over-tightening of bolts and nuts causes them to come off or their threads to be damaged.
Insufficient tightening causes oil leakage from the installation face or troubles due to the
loosening of bolts. Nuts and Bolts must be tightened to the appropriate tightening torque.
Important parts must be tightened with a torque wrench to the correct tightening torque and in
the right order. Consult with your dealer or distributor if the servicing requires the removal of
such parts.
The tightening torque for standard nuts & bolts is listed below:
[NOTICE]
Apply the following tightening torque to bolts having " 7 " on the head.
(JIS strength classification : 7T)
Tighten bolts with no " 7 " mark to 60% tightening torque.
If the parts to be tightened are made from aluminum alloy, tighten the bolts to
80% tightening torque.
Bolt dia. pitch mm
N . m
Tightening torque
(Kgf-m)
M6 1.0 M8 1.25
10.8 1.0 25.5 2.9
(1.1 0.1) (2.6 0.3)
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42
See [4.1 Inspection Before Starting]
M10 1.5 M12 1.75 M14 1.5
49.0 4.9 88.3 9.8
(5.0 0.5) (9.0 1.0)
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M16 1.5
137 9.8 226 9.8
(14.0 1.0) (23.0 1.0)