Operation CHARM: Car repair manuals for everyone.

Compression Check: Testing and Inspection

Compression pressure, checking/values

Test conditions
- engine oil temperature minimum 30°C (86°F)
- throttle plate completely open
- fuse 18 removed
- ignition coil lead removed from ignition distributor

- check compression with pressure recorder US 1120
- follow recorder instructions

- operate starter until recorder unit indicates no further pressure increase

Pressure values, bar (psi)

New Wear limit
11-13 (160-189) 7.5 (109)

- maximum permissible difference between all four cylinders: 3 bar (43.5 psi)