Trouble Shooting (Engine)
DETROIT DIESEL 53
ABNORMAL ENGINE OPERATION
1. Check the engine coolant temperature gage and, if
exhaust back pressure. Clean, repair or replace faulty
the temperature does not reach 160 o to 185 oF. while
the engine is operating, consult the Abnormal Engine
Check the compression pressures (consult the Hard
Coolant Temperature chart.
2. Check engine fuel spill back and if the return is less
9. Incorrect operation of the engine may result in
than specified. consult the No Fuel or Insufficient Fuel
excessive loads on the engine. Operate the engine
according to the approved procedures.
3. Check the injector timing and the position of the
10. Refer to Item 13 on Chart 4.
injector racks. If the engine was not tuned correctly,
perform an engine tune-up. Erratic engine operation
11. Check the ambient air temperature. A power
may also be caused by leaking injector spray tips.
Replace the faulty injectors.
depending upon injector size, for each 10 oF.
temperature rise above 90 oF. will occur. Relocate the
4. Check the compression pressures within the
engine air intake to provide a cooler source of air.
cylinders and consult the Hard Starting chart if
compression pressures are low.
12. Engines lose horsepower with increase in altitude.
The percentage of power loss is governed by the
5. Erratic engine operation may be caused by
altitude at which the engine is operating.
governor-to-injector operating linkage bind or by
faulty engine tune-up. Perform the appropriate engine
13. Fill oil bath air cleaners to the proper level with
tune-up procedure as outlined for the particular
the same grade and viscosity lubricating oil that is
used in the engine.
Clean the air box and drain tubes to prevent
6. Perform an engine tune-up if performance is not
accumulations that may be picked up by the air stream
and enter the engine s cylinders.
Check the engine gear train timing. An improperly
Inspect the blower oil seals by removing the air inlet
timed gear train will result in a loss of power due to
housing and watching through the blower inlet for oil
the valves and injectors being actuated at the wrong
radiating away from the blower rotor shaft oil seals
time in the engine s operating cycle.
while the engine is running. If oil is passing through
the seals, overhaul the blower.
7. Perform a Fuel Flow Test and, if less than the
specified fuel is returning to the fuel tank, consult the
Check for a defective blower-to-block gasket. Replace
No Fuel or Insufficient Fuel chart.
the gasket, if necessary.
8. Check for damaged or dirty air cleaners and clean,
14. Refer to Item 1 of this chart.
repair or replace damaged parts.
15. Check injector timing and the position of each
Remove the air box covers and inspect the cylinder
injector rack. Perform an engine tune-up, if necessary.
liner ports. Clean the ports if they are over 50%
If the engine is correctly tuned, the erratic operation
may be caused by an injector check valve leaking,
spray tip holes enlarged or a broken spray tip. Replace
Check for blower air intake obstruction or high
SEC. 15.2 Page 9