Inspection Every 2000 Hours Or 2 Years - Yanmar 3TNV Series Service Manual

2. Inspection and Adjustment

2.2.7 Inspection every 2000 hours or 2 years

Be sure to check the following points every 2,000 hours or two years operation, whichever comes first.
No.
(1) Coolant water path flushing and maintenance
(2) Fuel pipe and coolant water pipe inspection and maintenance
(3) Intake/exhaust valve seat lapping
Fuel injection timing adjustment
(4)
Fuel injection pump inspection and adjustment
(1) Coolant water path flushing and maintenance
Rust and water scale will accumulate in the cooling system through many hours of operation. This
lowers the engine cooling effect. Oil coolers (attached to turbocharged engines and some of naturally
aspirated engines) quickly deteriorate the lube oil. The cleaning and maintenance of the following
parts are necessary in accordance with the coolant water replacement.
Cooling system parts: radiator, cooling water pump, thermostat, cylinder block, cylinder head, oil cooler.
(2) Fuel pipe and coolant water pipe inspection and maintenance
Regularly check the rubber hoses of the fuel system and cooling water system. If cracked or degraded,
replace them with new one. Replace the rubber hoses at least every 2 years even if 2,000 hours
doesn't come.
(3) Intake/exhaust valve seat lapping
The adjustment is necessary to maintain proper contact of the valves and seats. Refer to 4.2.6 in Chapter 4.
(4) Fuel injection timing adjustment / Fuel injection pump inspection and adjustment
The fuel injection timing and the fuel injection pump are adjusted so that engine performance may
become the best condition. As for the inspection and adjustment of the fuel pump, it is based on the
service manual of the MP pump of the separate volume. The fuel injection timing is adjusted by the
following procedure.
As for the engine, which adopts a MP type fuel
injection pump, the fuel injection angle
adjusted for the fuel injection timing adjustment,
because the adjusting method of fuel injection timing
li ke an inline fuel pump can't be applied.
Note) The fuel injection angle
difference from the injection valve opening
angle while the fuel injection pump being driven
by a motor and the angle at the plunger lift
2.5mm of the fuel pump.
And, as for the actual fuel injection angle
the measured value is recorded on the pump
body by each every fuel pump.
The adjustment of fuel injection angle
In case that a fuel pump cover, installed with a gear
case cover and the fuel pump are removed, and
reassembled, the procedure of fuel injection angle
adjustment is as follows. (As for the disassembly of
a fuel injection pump, refer to 7.2.3 in chapter 7.)
[NOTICE]
Never loosen four flange bolts, which fasten a pump
flange and a fuel pump drive gear at the time of the
removal of the fuel pump. When it is loosened, the
adjustment of the fuel injection timing becomes very
difficult.
Inspection Item
θ
(note) is
i
θ
(cam angle) is the
i
θ
,
i
θ
i
46