whats causing my r reg 1.4 merit astra to overheat?

yeah the radiator is still cool, when the gauge has gone up. Have just bought a new theromstat that a friend is going to put on for me. Hopefully thatll be it. Thanks for all advice, will let ya all know if it works.

welshbyrd
April 2009

Hitting the red after only a few mins i would think its a faulty gauge.best bet is to turn on ignition 1st thing in the morning and see if it gos straight to red.if it does then no immidiate worry but will need sorting as soon as,summers coming and you really need a gauge but car will be drivable.if it stays at the bottom but heats up fast when driving then as already suggested i would have the thermostat tested then it can only be a blockage or waterpump,but water pumps often leak when they fail

mikc
April 2009

OK, as the water is actually there...you probably have a thermostat problem - this thing opens automatically when the engine reaches 90 deg C and allows the cooling water to circulate through the radiator, keeping the water temperature constant.
Or - the temperature gauge may just have gone faulty!
To sort of check the thermostat, when the temperature gauge reads very hot, feel the surface of the radiator - chances are its still cool. This is not a guaranteed test though! Watch out for the electric cooling fan - they start automatically.

John
April 2009

checked the radiator, doesnt seem to be a problem there, and water wasnt oily.

welshbyrd
April 2009

If the car gets so hot after such a short drive, you can expect the thermostat to have failed, but check the water level in the radiator first - and look for any signs of an oily emulsion in there.

John
April 2009