OM 617 – Checking cylinders for leakage

Total pressure loss max. 25 %
at valves and cylinder head gasket max. 10 %
at pistons and piston rings max. 20 %

1 Warm up engine to operating temperature.
2 Unscrew glow plugs.
3 On engine models 615 and 616 featuring injection pumps with pneumatic governors, detach rubber gaiter at throttle body and set throttle valve to full delivery.
On engines featuring injection pumps with mechanical governors, detach air filter.
4 Remove oil filler cap.
5 Remove radiator cap and top up coolant.
6 Screw connector into glow plug hole of No. 1 cylinder.
7 Set piston of No. 1 cylinder t o ignition TDC.
To do so, turn engine at crankshaft, using tool combination.
8 Connect cylinder leakage tester to air system Calibrate tester.
9 Screw tester connecting hose to connector.
Make sure that crankshaft does not turn.

10 Note pressure loss on tester.
11 Listen to check whether pressure escapes through intake pipe, exhaust, oil filler cap, glow plug hole of adjacent cylinder or radiator cap.
12 Check all cylinders in firing order.

Note: The reading will be falsified if the piston ring gaps of a particular piston are directly above one another.
In case of doubt, continue to run engine and then check cylinders for leakage again after some time has elapsed.

Leave a Reply

Your email address will not be published. Required fields are marked *