Power Solutions International — Cylinder Leakage Test
Testing & diagnosis · Engine
From a Power Solutions International service manual — check it applies to your exact model before use.
Applies to: General Motors 8.8L engine
Before you start
- It may be necessary to hold the crankshaft balancer bolt to prevent crankshaft rotation
Procedure
- Disconnect the battery ground negative cable.
- Remove the spark plugs.
- Rotate the crankshaft to place the piston at Top Dead Center of compression stroke.
- Install the cylinder leak down tester.
- Apply shop air pressure and adjust according to manufacturer's instructions.
- Record the cylinder leakage value.
- Perform the leakage test on the remaining cylinders and record the values.
Tools required
- Cylinder Head Leakdown Tester Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Cylinder leakage that exceeds 25 percent is considered excessive
Source: Power Solutions International service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.