Spark Plugs; Drive Belt Adjustment - Westerbeke BTG 8.5 Operator's Manual

ENGINE ADJUSTMENTS
SPARK PLUGS
The spark plugs should be cleaned and regapped after the
first 50 hour break-in period, then inspected every 250 hours
thereafter and replaced as needed.
A
WARNING:
Do not remove the spark plugs while
the engine is hot. Allow the engine to cool before
removing them.
SPARK PLUG GAP: 0.031-
±
0.0002 in. (0.8-0.05 mm).
SPARK PLUG TORQUE: 10 -151b·ft (1.5 -2.31 kg-m).
NOTE:
Loctite Anti-Seize applied to the threaded ponion of
the spark plugs will retard corrosion, making future removal
of the spark plugs easier.
INSPECTING
THE SPARK
PLUGS
CHECK FOR
CARBON AND
BURNING
DRIVE BELT ADJUSTMENT
The drive belts must be properly tensioned. Excessive drive
belt tension can cause rapid wear ofthe belts and reduce the
service life of the bearing and the alternator, raw water pump,
and engine coolant pump. A slack belt or the presence of oil
on the belt can cause belt slipping, resulting in high operating
temperatures and the failure of the same components.
1. To adjust the alternator and the engine coolant belts,
loosen the alternator mounting bolts and pivot the
alternator as needed. Retighten the bolts.
2. To adjust the raw water pump belt, loosen the mounting
bolts and slide the pump up and down as needed.
Retighten the bolts.
NOTE:
When the belts are loose, inspect for wear, cracks and
frayed edges, and replace
if
necessary.
3. The drive belts are properly adjusted if it can be deflected
no less than 3/8 inch (lOmm) and no more than 1/2 inch
(12mm) as the belt is depressed with the thumb at the
midpoint between the two pulleys on the longest span of
the belt.
4. Operate the engine for about 5 minutes, then shut down
the engine and recheck the belts tension.
NOTE:
Maintain a 22 lb pressure to the belt's outer face for
proper belt operation. Spare belts should always be car-
ried on board.
21
A
WARNING:
Never attempt to check or adjust a
drive belt's tension while the engine is in operation.