Ignition Wires; Engine Compression Test; Torquing The Cylinder Head Bolts - Westerbeke W-70GA Operator's Manual

ENGINE ADJUSTMENTS
NOTE:
WESTERBEKE recommends that the following engine adjust-
ments be performed by a competent engine mechanic. The information
below is provided to assist the mechanic.
TORQUING THE CYLINDER HEAD BOLTS
After the initial break-in period (approximately 50 hours), the
cylinder head bolts should be re-torqued.
Tighten the cylinder head bolts according to the sequence
shown. Make sure the engine is cold when this is done, and
loosen one head bolt one-half turn and then tighten it
between 55 - 59 lb-ft (8.2 - 8.8 Kg-rn). Then proceed to the
next head bolt in the sequence. Tighten the RS (rocker cover
stud) securely.
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3
HIGH TENSION CORDS (IGNITION WIRES)
Check the ignition wires every 500 operating hours as engine
compartment heat can deteriorate the wires.
Check the resistance of each wire. Do not pull on the wire
because the wire connection inside the cap may become
separated or the insulator may be damaged. When removing
the wires from the spark plugs, grasp and twist the molded
cap, then pull the cap off the spark plug.
THE RESISTANCE VALUE IS 410 OHM PER INCH.
TESTING
RESISTANCE
4
ENGINE COMPRESSION
If it becomes necessary to check the engines cylinder
compression, warm the engine and shut it down.
Remove the spark plugs and install a compression adapter
(screws into a plug hole) with a gauge.
Crank the engine (close off the raw water) and unplug the
ignition coil. Allow the compression gauge to reach a
maximum reading and record.
Measure the compression pressure for each cylinder. Ensure
that the pressure differential for each cylinder is within the
specifications.
COMPRESSION PRESSURE AT 1400 RPM
LIMIT OF DIFFERENCE BETWEEN CYLINDERS
198.1 psi (14 kg/em')
28.0 psi (2.0 kg/em')
If a cylinder's compression or pressure differential is below
the limit, add a small an10unt of engine oil through the spark
plug hole and repeat the test. If the oil causes an increase of
pressure, the piston ring andlor cylinder wall may be worn or
damaged. If the added oil does not increase compression
pressure suspect poor valve contact, valve seizure, or valve
wear. Reinstall the plugs, ignition wires, and coil. Open the
raw water tbru seacock.
Engines & Generators
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