Testing Engine Compression; Fuel Injectors - Westerbeke 44A FOUR-35 C THREE Operator's Manual

ENGINE ADJUSTMENTS
NOTE:
WESTERBEKE recommends that the following engine adjust-
ments be peiformed by a competent engine mechanic. The information
below is provided to assist the mechanic.
TESTING ENGINE COMPRESSION
Make certain the oil level (dipstick) is at the correct level and
the air intake filter is clean. The battery and starter motor
must also be in good condition.
1. Warm the engine to normal operating temperature.
2. Move the control lever to a position for shutting off the
fuel. (Disconnect the wires if a fuel shutdown solenoid is
used).
3. Remove all the glow plugs from the engine and install
the compression gauge/adapter combination to the cylin-
der on which the compression is to be measured.
TESTING ENGINE
COMPRESSION
ADAPTER
~WPLUGHDLE
PRESSURE
GAUGE
4. Close the raw water seacock (thru-hull).
5. Crank the engine and allow the gauge to reach a
maximum reading, then record that reading.
6. Repeat this process for each cylinder.
Compression pressure 427 psi (30 kgf/cm2) at 290 rpm.
Maximum permissible difference between cylinders is 42.7 psi
(3 kgf/cm2)
NOTE:
lfthe readings are below the limit, the engine needs
repair
7. Re-install the glow plugs (use anti-seize compound on
the threads) and reset the fuel shut-off to the run position.
8. Open the raw water seacock (thru-hull).
LOW COMPRESSION
When low compression is found, determine the cause by
applying a small amount of oil in the cylinder thru the glow
plug hole. Allow the oil to settle.
Install the pressure gauge and repeat the above test. If the
compression reading rises dramatically, the fault is with the
rings. If the compression valve does not rise, the problem is
with the valves.
A slight rise in compression would indicate a problem with
both the rings and the valves.
FUEL INJECTORS
In case of severe vibrations and detonation noise, have the
injectors checked and overhauled by an authorized fuel
injection service center. Poor fuel quality, contaminants and
loss of positive fuel pressure to the injection pump can result
in injector faults. Since fuel injectors must be serviced in a
clean room enviroment, it is best to carry at least one extra
injector as a spare should a problem occur.
Before removing the old injector, clean the area around the
base of the injector to help prevent any rust or debris from
falling down into the injector hole. If the injector will not lift
out easily and is held in by carbon build-up or the like, work
the injector side-to-side with the aid of the socket wrench to
free it, and then lift it out.
The injector seats in the cylinder head on a copper sealing
washer. This washer should be removed with the injector and
replaced with a new washer when the new injector is
installed.
Injector to Cylinder Head Tightening Torque 40 ± 4 ft-lb (5.5
±
0.5 kgf-m)
FUEL INJECTOR
Engines & Generators
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