Engine Symptoms Diagnostics; Air Compressor Leak Test - Navistar International DT 466 Diagnostic/Troubleshooting Manual

110
9. Remove the oil pan following the procedure in the
Engine Service Manual.
10. Install radiator pressure
appropriate adapter.
WARNING: To avoid serious personal
injury, possible death and damage to the
engine:
• Always allow the engine to cool for 15
minutes.
• Wrap a thick cloth around the cap.
• Loosen cap slowly a quarter to half turn.
• Pause for a moment to avoid water or
steam scalding.
• Continue to turn the cap and remove.
• Never add cold coolant to a hot engine.
This can result in a cracked cylinder head
or crankcase.
• Never use water as a coolant substitute.
Figure 124 Bottom of engine
11. Pressurize cooling system to 96 kPa (14 psi).
Look for coolant leaks.
• If the engine is equipped with an air
compressor, and
compressor oil drain-back hose or from the
left side of the front cover, do "Air Compressor
Leak Test."
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.

4 ENGINE SYMPTOMS DIAGNOSTICS

tester with the
is leaking from the
EGES-270-1
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.
• If the engine does not have an air compressor,
and is leaking from the front cover area or the
oil pick-up tube, do "Front Cover Inspection"
(page 111).
• If a leak is noticed between the cylinder
sleeve and piston, replace the injector sleeve
for that cylinder. Follow the procedure in the
Engine Service Manual.
• If a leak is noticed between the cylinder
sleeve and the engine block, replace the
cylinder sleeve crevice seal for that cylinder.
Follow the procedure in the Engine Service
Manual.
• If a leak is noticed from the oil drain-back ports
(camshaft side), do "Cylinder Head Leak Test"
(page 112).
• If no leak is noticed, leave pressure on cooling
system overnight and check the following day.
• If no leak is noticed after overnight pressure
test, do the following sequential tests until
problem is found:
A. "Front Cover Inspection" (page 111)
B. "Cylinder Head Leak Test" (page 112)
12. After any repairs are complete, test the cooling
system again to validate the repair.

Air Compressor Leak Test

Figure 125 Air compressor test setup
1. Drain coolant from the system.