Engine Compression Test; Ignition Tirning - Westerbeke 8.0KW-60HZ Operator's Manual

ENGINE ADJUSTMENTS
NOTE:
WESTERBEKE recommends that the following engine
adjustments be pelformed by a competent engine mechanic.
The information below is provided to assist the mechanic.
ENGINE COMPRESSION TEST
1. To check the engine's compression pressure, warm up the
engine then shut it down.
2. Remove the spark plugs and install a compression adapter
(screws into a plug hole) with a gauge.
3. Close
0[[
the raw water intake seacock.
4. Crank the engine with the start motor and unplug the
ignition coil and allow the compression gauge to reach a
maximum reading and record.
5. Measure the compression pressure for all the cylinders.
Ensure that compression pressure differential for each
cylinder is within the specified unit.
Compression pressure should not differ by more than 14 psi (100 Kpa).
6. If a cylinder's compression or pressure differential is
below the limit, add a small amount of engine oil through
the spark plug hole and repeat steps 3 and 4.
(a) If additional of oil causes an increase of pressure, the
piston ring and/or cylinder wall may be worn or damaged.
(b) [f additional oil does not increase compression pres-
sure suspect poor valve contact, valve seizure, or valve
wear.
7. Reinstall plugs and ignition wires.
8. Open the raw water thru seacock.
MEASURING
COMPRESSION
DIAL GAUGE
Standard Compression
(limit of difference
between cylinders)
165 p.s.i. at 300 rpm
14 p.s.i.
IGNITION TIMING
1. Attach a timing light to the
#1
spark plug and mark the
front crankshaft timing groove and the timing mark on the
scale embossed on the engine's front cover.
Each timing mark represents 5°.
CRANKSHAFT
PULLEY
2. Start the engine and warm the engine to its normal
operating temperature.
3. Using the timing light, align the timing groove in the front
crankshaft pulley with the proper timing mark on the igni-
tion timing scale embossed on the engine's front cover.
Do this by loosening and slowly rotating the distributor
body. Refer
to
the timing specifications:
IGNITION TIMING AT 1800 RPM: 20° BTDC ± 1°.
Engines & Generators
27 REVISED AUGUST 2004