Tools Required

J 26999-30 Compression Gauge Adapter

1. Remove the air cleaner.
2. Disconnect the pink wire from the fuel solenoid terminal of the injection pump.
3. Disconnect the wires from the glow plugs. Remove all the glow plugs.
4. Screw J 26999-30 into the glow plug hole of the cylinder that is being checked. Connect to the compression gauge.
5. The batteries must be fully charged.
6. The engine must be warmed up (engine oil is hot).
7. Crank the engine. Allow six puffs per cylinders.

NOTICE: Do not add oil to any cylinder during a compression test as extensive engine damage can result.

8. Make the compression check at each cylinder. Record the readings.
9. The lowest reading cylinder should not be less than 80 percent of the highest reading cylinder. No cylinder should read less then 2625 kPa (380 psi).
10. Normal compression builds up quickly and evenly to the specified compression on each cylinder. Readings should be in the range of 2625-2760 kPa (380-400 psi).
11. Leaking compression is low on the first stroke and tends to build up on the following strokes but does not reach normal.