Compression Pressure
EM-199prose procedureApplies to CD20 (diesel) engine.
Compression Pressure (continued)
- 6Fit compression gauge to cylinder head.
SEM505D - 7Crank engine and read compression gauge indication.Cranking speed: 200 rpm
- 8If the pressure appears low, pour about 3 mℓ (0.11 Imp fl oz) of engine oil through nozzle holes and repeat test. For indications of test, refer to the following table.
| Specification | Value |
|---|---|
| Cranking speed | 200rpm |
| Compression pressure (Standard) | 2,942 - 3,236kPa29.4 - 32.4, 30 - 33bar, kg/cm²427 - 469psi |
| Compression pressure (Limit) | 2,452 (24.52, 25.0, 356)kPa (bar, kg/cm², psi) |
| Limit of difference between cylinders | 490 (4.90, 5.0, 71)kPa (bar, kg/cm², psi) |
Cranking speed
200rpm
Compression pressure (Standard)
2,942 - 3,236kPa29.4 - 32.4, 30 - 33bar, kg/cm²427 - 469psi
Compression pressure (Limit)
2,452 (24.52, 25.0, 356)kPa (bar, kg/cm², psi)
Limit of difference between cylinders
490 (4.90, 5.0, 71)kPa (bar, kg/cm², psi)
Compression test trouble diagnosis
Reading increases on second test (after adding oil) — first reading vs second/increased reading
Trouble diagnosisPiston rings are worn or damaged.
Same reading maintained on second test (no change after adding oil)
Trouble diagnosisIf two adjacent cylinders are low, gasket is damaged. Valve is sticking. Valve seat or valve contact surface is incorrect.