Testing Cylinders For Leaks
Cylinder Leakage Test1 Run engine until at normal operating temperature.
2 Blow out spark plug recesses with compressed air.
3 Remove spark plugs.
4 Top off coolant and leave filler opening at coolant expansion tank open.
5 Remove oil filler cap.
6 Remove air filter.
7 Connect cylinder leakage tester to a compressed air system and calibrate tester.
8 Position piston of No. 1 cylinder to ignition TDC. This is done by turning the crankshaft with a tool combination consisting of wrench socket (27 mm, 1/2" square) and reversible ratchet handle, at the central bolt (front of crankshaft).
Note: The respective pistons are in the TDC position when the markings shown in the drawing opposite on the vibration damper or on the belt pulley are below the TDC pointer.
9 Open throttle fully.
10 Screw connection hose into the 1st spark plug bore and attach to the connecting hose of the tester. The crankshaft must not turn when performing this step.
11 Read off pressure loss at tester.
Specified Cylinder Leakage Limits
Total pressure loss: max. 25 %
Through valves and cylinder head gasket: max. 10 %
Through pistons and piston rings: max. 20 %
12 Determine by listening whether the pressure escapes through intake manifold, exhaust, oil filler opening, spark plug bore of adjacent cylinder or coolant filler opening.
13 Test all the cylinders in the firing order.