overheating problem

[deepblue]

Friends,

Na browse ko na buong tsikot concerning my overheating problem pero none is similar kaya I started this new thread. My ride is Revo 2000. Recently, i experienced engine overheat. What I did is I turned off the a/c, waited for 10 secs, then turn the a/c on again and presto, back to normal temp yung engine. I did it without stopping or turning off the engine. What could be the possible culprit? Isa lang ang fan ng REVO, my a/c was cleaned about a month ago, oks naman coolant level. Di ko lang alam kung sa talyer o sa aircon shop ko dadalhin ang ride ko. Pls help.

thanks

[albert_b]

Have you checked whether your fans (main + aux) are still working?

You might also want to invest on some coolant ;-)

[deepblue]

Thanks sa reply sir, kapapalit ko lang ng coolant about 3 months ago. Yung REVO naman has no aux fan, 1 radiator fan lang. Funny thing is, occasional lang yung overheating problem. Posible kayang battery? more than 2 years na kasi battery ko.
thanks again

[purple0rkid]

malamang slipping compressor clutch yan. madali lang i-repair yan sa mga suking talyer.

[mikaztro]

Engines are designed to operate within a "normal" temperature range of about 190 to 220
degrees F. A relatively consistent operating temperature is absolutely essential for proper
emissions control, good fuel economy and performance.


Possible problems:

1. Make sure it is really running hot. It may be a failed temperature sending unit. Check the coolant temperature with an accurate temperature measuring device.

2. If it really is running hot check the thermostat.Severe overheating can often damage a good thermostat. Therefore, if the engine has overheated because of another problem, the thermostat should be tested or replaced. One way to check the thermostat is to start the engine and feel the upper radiator hose. The hose should not feel uncomfortably hot until the engine has warmed-up and the thermostat opens. If the hose does not get hot, it means the thermostat is not opening.

3. Check the Belts & hoses: Check belt tension and condition. A loose belt that slips may prevent the water pump from
circulating coolant fast enough and/or the fan from turning fast for proper cooling.Check if there are leakages in your hoses(collapsed lower radiator hose).

4. Check the cooling fins on the radiator to ensure that they are firmly attached to the cooling tubes. Check for defective radiator cap.

5. Check your aux fans if they are running properly according to their specified RPMs. Are they turning on while idling on traffic?
(inoperative electric cooling fan)

6. Check for slipping clutch fan

7. Check for eroded or loose water pump impeller. Water pump can cause an engine to overheat if the impeller vanes are badly eroded due to corrosion or if the impeller has come loose from the shaft.

If the engine overheats and exceeds its normal operating range, the elevated temperatures can cause extreme stress in the cylinder head which may result in a head gasket failure.

If the engine overheats despite all, then you have no choice but to do Cylinder hydro test or top overhaul.