User Manual

Page 9-8
200 TROUBLESHOOTING
HIGH EXHAUST TEMPERATURE
200780a
Possible Cause Correction
1. Operating chassis in wrong gear ratio for load,
grade and/or altitude.
1. Instruct operator on correct gear selection for load and grade
conditions.
2. Restrictions in the air induction system. 2. Inspect air induction system. Remove restrictions and/or replace
defective parts.
3. Air leaks in the air induction system. 3. Check pressure in the air intake manifold. Look for leaking piping,
and/or loose clamps. Make necessary repairs.
4. Leaks in the exhaust system (before the
turbocharger).
4. Check exhaust system for leaks. Make necessary repairs.
5. Incorrect fuel injection pump-to-engine timing. 5. Check fuel injection pump-to-engine timing. Adjust as required.
6. Restrictions in the exhaust system. 6. Inspect system. Make necessary repairs.
7. Improper valve lash adjustment. 7. Adjust valve lash setting to specified clearance.
8. Defective fuel injection nozzle assembly. 8. Isolate defective nozzle assembly. Remove, repair and/or replace
and reinstall.
9. Incorrect fuel injection pump calibration. 9. Remove injection pump and nozzle assemblies. Send fuel
injection pump to an authorized MACK Fuel Injection System
Repair facility for recalibration. Then reinstall the pump and nozzle
assemblies.
High Pyrometer — Normal Boost
10. Loose ducting. 10. Repair loose connections.
11. Core fin obstructions. 11. Clean core fins.
High Pyrometer — Low Boost
12. Blockage in ducting between the air cleaner
and the turbocharger.
12. Check for blockage and repair.
13. Dirty turbocharger. 13. Remove turbocharger and clean.
14. Leaks in the pressurized side of the air
induction system.
14. Check for leaks. Repair as required.
15. Core leak or inlet manifold leak. 15. Check for damaged core gaskets.
16. Open petcock. 16. Close petcock.
17. Core leakage. 17. Pressure test core. Remove, repair or replace core if test results
are unsatisfactory.
5-101.bk Page 8 Friday, March 17, 2006 11:05 AM