Compression Pressure Check; Compression Test Procedure - Suzuki DL650 Service Manual

2-30 PERI O DI C MAI N TENANCE
COMPRESSION PRESSURE CHECK
The compression of a cylinder is a good indicator of its internal condition.
The decision to overhaul the cylinder is often based on the results of a compression test. Periodic mainte-
nance records kept at your dealership should include compression readings for each maintenance service.
COMPRESSION PRESSURE SPECIFICATION (Automatic de-comp. actuated)
Low compression pressure can indicate any of the following conditions:
*
Worn-down piston or piston rings
*
Piston rings stuck in grooves
*
Poor seating of valves
*
Ruptured or otherwise defective cylinder head gasket
Overhaul the engine in the following cases:
*
Compression pressure in one of the cylinders is 1 100 kPa (1 1 kgf/cm2, 156 psi) and less.
*
Difference in compression pressure between two cylinders is 200 kPa (2 kgf/cm2, 28 psi) and more.
*
All compression pressure are below 1 300 kPa (13 kgf/cm2, 185 psi) even when they measure 1 100 kPa
(1 1 kgfIcm2, 156 psi) and more.
COMPRESSION TEST PROCEDURE
NOTE:
*
Before testing the engine for compression pressure, make
sure that the cylinder head bolts are tightened to the specified
torque values and valves are properly adjusted.
*
Have the engine warmed up by idling before testing.
*
Be sure that the battery used is in fully-charged condition.
Remove the parts concerned and test the compression pressure
in the following manner.
Lift and support the fuel tank. ( W 5 - 7 )
Remove all the spark plugs.
( - 2 - 6 )
Fit the compression gauge in one of the plug holes, while tak-
ing care of the tight connection.
Keep the throttle grip in full-open position.
While cranking the engine a few seconds with the starter, and
record the maximum gauge reading as the compression of
that cylinder.
Repeat this procedure with an other cylinder.
a
0991 5-6451 2: Compression gauge
0991 3-1 0750: Adaptor