A few weeks back my magna had some wierd problems where when it was hot, it would start make a top end ticking noise and when I continued to drive it, it stalled and wouldnt turn over. Anyway, the mechanic serviced the radiator as it had a rather big hole in it, though now the car is over heating after about 20kms of driving. I have replaced the thermostat but the overheating is still occuring. There is no oil in the radiator, and no water in the oil, so im guessing its not a head gasket problem. What else could it be? There is no leaks under the car at all.

A few weeks back my magna had some wierd problems where when it was hot, it would start make a top end ticking noise and when I continued to drive it, it stalled and wouldnt turn over. Anyway, the mechanic serviced the radiator as it had a rather big hole in it, though now the car is over heating after about 20kms of driving. I have replaced the thermostat but the overheating is still occuring. There is no oil in the radiator, and no water in the oil, so im guessing its not a head gasket problem. What else could it be? There is no leaks under the car at all.


does the engine light appear when this happens, it could be your coolant temp sensor causing issues with the fans not coming on??

Engine light doesnt appear to come on, and the thermos seem to be working. I can hear the water boiling which isnt a good sign. I havent had a chance to check the water level yet, because its still to hot.

"I have replaced the thermostat but the overheating is still occuring. "

is it possible you fitted this the wrong way around? Also re above comment re temp sensor and fans you did't clearly answer - does the main fan come on just after warm? (mid point on the gauge). What is the temperature gauge saying when this boiling sound happens?

Could be a busted fuse for the cooling fan.

put some water in it:bowrofl:

Engine light doesnt appear to come on, and the thermos seem to be working. I can hear the water boiling which isnt a good sign. I havent had a chance to check the water level yet, because its still to hot.


sounds to me like it is the coolant temp sensor, but then again it could be something else, check the sensor anyways they are only $25 from repco trade price and it may fix your issue!!

what about the water pump?

Is there a easy way to test if its the water pump or a sensor?

Is there a easy way to test if its the water pump or a sensor?

If you know where the sensor is, unplug it and unscrew it and see if its rusted or corroded, if so its most likely faulty, make sure its plugged in correctly and the lead is not damaged etc!!

Anyway, the mechanic serviced the radiator as it had a rather big hole in it, though now the car is over heating after about 20kms of driving.

Just how big was this hole and what did your mechanic do to fix it? - im thinking 2 things here.....1. your mechanic may have stuffed up in repairing the hole and effectivly blocked the water fins in the repair area, reducing water flow through the radiator - in turn reducing the rate at which water can flow throughout the whole system - 2. whatever method your mechanic used to repair said hole could have resulted in residue blocking even more water fins, reducing flow even further

You say you travel about 20km before it overheats - sounds like a gradual build up of heat, and you water stsyem isnt flowing fast enough through the radiator too keep the water at the correct temp.....sounds quite feasable to me......

Is there a easy way to test if its the water pump or a sensor?

A complete water pump failure without visible leaking would be rare, wheras fried sensors from overheating are quite likely.

There are 2 sensors with wires coming off them on the top of the thermostat housing near where the top radiator hose goes into the engine. With the car cold, remove the wire off the larger sensor and briefly start the car. Check if the main radiator fan is running, then shut off the car (ie don't run it too long with that wire off). During this test, if the fan doesn't run, its a fan or fan wiring problem, if the fan runs, the sensor is faulty.