Generac Power Systems MAC 750F Owner's Manual page 24

Troubleshooting
Problem
Exhaust Smoke is White
Exhaust smoke is Black
Engine Overheats
Oil Pressure Does Not Rise
Engine Has No Power
Overheat/shutdown condition
20
Cause
Needs more warm-up time.
Too much engine oil.
Engine control system fails.
Injection pump failure.
Fuel system failure.
Long time idling (more than two hours).
Excessive speed.
Injection pump failure.
Air cleaner is clogged.
Intercooler is clogged.
Fuel system failure.
Exhaust system is clogged.
No coolant.
Front of radiator is clogged with dust.
Sub tank cap is not tightened.
Coolant is fouled.
Oil is in coolant.
Thermostat failure.
Engine oil viscosity is incorrect.
Engine oil level is not sufficient.
Engine failure.
Meter, lamp or switch failure.
Air cleaner is clogged.
Pre-fuel filter is clogged.
Fuel filter is clogged.
Strainer is clogged.
Engine control system failure.
Engine failure.
Exhaust system is clogged.
Fuel system failure.
Type of fuel is incorrect.
Electromagnetic type fuel pump failure.
Access doors are open
Air outlets are not open
Front radiator or rear oil cooler are full of
debris
Engine RPM is set too high based on
ambient temperature
Faulty temperature sensor
Blower fan not operating correctly
Solution
Conduct warm-up operation.
Correct oil level.
Contact Generac Technical
Service.
Keep stopping the equipment and
press throttle pedal.
Verify engine RPM.
Check AVR adjustment.
Contact Generac Technical
Service.
Clean or change element.
Contact Generac Technical
Service.
Add coolant.
Clean with soft brush.
Tighten or replace sub tank cap.
Clean inside of radiator and
change coolant.
Contact Generac Technical
Service.
Change thermostat.
Change with oil of correct viscosity.
Replenish.
Contact Generac Technical
Service.
Clean element.
Remove water and change
element.
Contact Generac Technical
Service.
Close all access doors
Open the air outlets and verify
there are no obstructions or kinks
in the ducting
Clean the machine
Lower the engine RPM
Check air outlet sensor operation
Remove ducting; check blower fan
operation
Owner's Manual for Flameless Air Heater