BMW E36 RADIATOR AND COOLING SYSTEM TROUBLESHOOTING - bmw e36 cooling system
Most cooling system faults can be grouped into one of three categories :
When investigating the cause of overheating or coolant loss, begin with avisual inspection . Be sure to check the condition and tension of the coolant pump drive belt. Check hoses for cracks or softness . Check clamps for looseness. Check the coolant leve¡ and check for evidence of coolant leaks from the engine.
Check that the radiator fins are not blocked with dirt or debris. Clean the radiator using low-pressure water or compressed air. Blow outward, from the engine side out.
Inspect the coolant pump by first removing the drive belt from the pump. Firmly grasp opposite sídes of the pulley and check for play in all directions. Spin the pulley and check that the shaft runs smoothly.
NOTE
The coolant provides lubrication for the pump shaft, so an occasional drop of coolant leaking from the pump is acceptable. If coolant drips steadily from the vent hole, the pump should be replaced.
The cooling system becomes pressurized at normal operating temperature, which raises the boiling point of the coolant. Leaks may prevent the system from becoming pressurized, allowing the coolant to boil at a lowertemperature. If visual evidence is inconclusive, a cooling system pressure test can help to pinpoint hard-to-find leaks.
If the cooling system is full of coolant and holds pressure, the next most probable cause of overheating are:
NOTE
* Some early style coolant pumps were fitted wíth fiberlplastic type impellers . Over time, this impeller can wear away and result in overheating. The plastic impeller can also slip or free-wheel on the pump shaft. If the engine overheats and no other faults can be found, the old style impeller may be the cause of the
problem.
* Only pumps with the updated metal impeller should be used for replacement.
- Cooling system leaks
- Poor coolant circulation
- Radiator cooling fan faults
When investigating the cause of overheating or coolant loss, begin with avisual inspection . Be sure to check the condition and tension of the coolant pump drive belt. Check hoses for cracks or softness . Check clamps for looseness. Check the coolant leve¡ and check for evidence of coolant leaks from the engine.
Check that the radiator fins are not blocked with dirt or debris. Clean the radiator using low-pressure water or compressed air. Blow outward, from the engine side out.
Inspect the coolant pump by first removing the drive belt from the pump. Firmly grasp opposite sídes of the pulley and check for play in all directions. Spin the pulley and check that the shaft runs smoothly.
NOTE
The coolant provides lubrication for the pump shaft, so an occasional drop of coolant leaking from the pump is acceptable. If coolant drips steadily from the vent hole, the pump should be replaced.
The cooling system becomes pressurized at normal operating temperature, which raises the boiling point of the coolant. Leaks may prevent the system from becoming pressurized, allowing the coolant to boil at a lowertemperature. If visual evidence is inconclusive, a cooling system pressure test can help to pinpoint hard-to-find leaks.
If the cooling system is full of coolant and holds pressure, the next most probable cause of overheating are:
- Faulty radiator fan
- Loose or worn drive belt
- Failed thermostat or coolant pump
- Clogged/plugged radiator or coolant passages
NOTE
* Some early style coolant pumps were fitted wíth fiberlplastic type impellers . Over time, this impeller can wear away and result in overheating. The plastic impeller can also slip or free-wheel on the pump shaft. If the engine overheats and no other faults can be found, the old style impeller may be the cause of the
problem.
* Only pumps with the updated metal impeller should be used for replacement.
BMW E36 RADIATOR AND COOLING SYSTEM TROUBLESHOOTING - bmw e36 cooling system Up
Read also: