If engine is not new or has not been rebuilt, refer to section 2.6.
To determine if a missing rocker arm shaft plugs are causing low oil pressure, perform the following steps:
1. Remove the rocker arm cover, (two piece, three piece); refer to appropriate service manual, engine chapter.
2. Visually inspect the rocker arm shaft for missing or leaking shaft plugs.
[a] If the shaft plugs are present and are not leaking, check the oil cooler for restriction;
refer to section 2.6.
[b] If the shaft plugs are missing, refer to section 2.5.2.
[c] If the shaft plugs are leaking, refer to section 2.5.1.
2.5.1
Leaking Rocker Arm Shaft Plug Repair
Perform the following steps to repair leaking rocker arm shaft plugs:
1. Remove damaged shaft plugs; refer to appropriate service manual, engine chapter.
2. Inspect rocker arm shaft for damage. If damage is found, replace the rocker arm shaft;
refer to appropriate service manual, engine chapter.
3. Install new shaft plugs; refer to appropriate service manual, engine chapter.
NOTE: Shaft plug must be installed 1.0 – 1.3 mm (0.040 -0.050 in.) below surface using J–36236.
4.5.Install rocker arm cover; refer to appropriate service manual, engine chapter.
Verify repair made to the rocker shaft plugs; refer to section 2.5.2.1.
2.5.2
Missing Rocker Arm Shaft Plug Repair
Perform the following steps to repair missing rocker arm shaft plugs:
1. Inspect rocker arm shaft for damage. If damage is found, replace the rocker arm shaft;
refer to appropriate service manual, engine chapter.
2. Install new shaft plugs; refer to appropriate service manual, engine chapter.
NOTE: Shaft plug must be installed 1.0 – 1.3 mm (0.040 -0.050 in.) below surface using J–36236.
3. Install rocker arm cover; refer to appropriate service manual, engine chapter.
4. Verify repair made to the rocker shaft plugs; refer to section 2.5.2.1.
2.5.2.1
Test Engine with Repaired Rocker Shaft Plugs
Perform the following steps to determine if repaired rocker shaft plugs resolved low oil pressure:
1. Connect to DDDL 7.0.
2. Start and run engine speed at 1800 rpm.
3. Check DDDL 7.0 for oil pressure reading.
[a] If DDDL 7.0 indicates 241 kPa (35 psi) or more at 1800 rpm, shut down the engine
and disconnect DDDL 7.0. No further troubleshooting is required.
[b] If DDDL 7.0 indicates less than 241 kPa (35 psi) at 1800 rpm, shut down the engine and disconnect DDDL 7.0. Check the oil cooler for restriction; refer to section 2.6.
