1. Bring the engine to operating temperature, with batteries fully charged.
2. Remove the B+ wire from the fuel shut-off solenoid wire on the injection pump.
3. Remove the glow plugs for all cylinders (use tool J 39084 to remove the glow plug wires for cylinders #4 and #6).
4. Install compression gauge adapter J 26999-10 into the glow plug hole of the first cylinder to be tested (see Figure 2-39, view A).
5. Connect compression gauge J 26999-12 to the adapter (see Figure 2-39, view B).
6. Crank the engine for six “ puffs,” observing the following
• Rate of pressure increase with each “ puff”
• Final pressure reading
7. Install the compression gauge and adapter in the next cylinder to be tested.
8. Test each cylinder, noting the pressure readings.
9. Analyze the test results:
• Pressure should build rapidly and evenly to a minimum of 2625 to 2760 kPa (380 to 400 psi).
• No cylinder should read less than 2625 kPa (380 psi).
• The lowest-reading cylinder should not be less than 80 percent of the highest-reading cylinder.
Note: Do not add oil to perform a “wet” test on any cylinder, as immediate engine damage will result.
10. Install the glow plugs (tighten to 11 to 16 N-m [8 to 12 Ib-ft] torque).
11. Connect the B+ wire for the injection pump fuel shut-off solenoid.
12. Check the engine operation and charge the batteries.