97 Corsa overheating?

[lee1933]

Hi,
I have just bought a '97, Corsa Breeze, 1.4, and the temp gauge quickly gets into the red.

The fan doesn't kick in, so I have bridged the connections so that it now runs with the ignition, but the gauge still hovers at the bottom of red.
I have run the car with the reservoir cap off, with the heaters on full, and it still climbs all the way up to the bottom of red. As soon as I stop the heaters and fan, the water starts to escape from the top of the res' and the temp gauge has shot to the top of red. I can't see any air bubbles though.

The thermostat has apparently been changed, but the upper pipe on the left hand side (as i'm stood looking at it = drivers side) is hotter than the pipes on the right.

I took it for a run and managed to keep the temp in the bottom of the red, got home, turned the engine off and removed the res' cap and there was no bubbling or hissing, so I am wondering if it could be a faulty sensor, or should I go ahead and change the water pump, etc? I would rather not have to start changing things that don't really need to be changed yet.

Thanks in advance for any advice

[phil w]

Are you loosing any water ? do you have any mayo in the oil at all ? ,if the answer to these 2 questions is no and if you are still getting hot air through the heater and the system is not presurising and boiling over ,
I would say try changing the temp sensor first

[lee1933]

Hi Phil. Thanks for the response!

There is no "mayo" in the oil at all, and the only time it loses water is if I take the res' cap off (water seems to swell out of the top) when the temp is up to the top of red, but saying that, I hear no hissing or gurgling before I remove the cap, but once I loosen the cap, water starts to escape. Now, when I have run the car with the heaters on, and then taken the res' cap off, no water escapes at all and the water in the res' is calm and I can dip my finger into the res' water without getting burned, yet the temp gauge will still be reading 105+ on the dash.

[vcorsab]

probably nothing to do with it but just throwing in ideas, could it be the head gasket ? cause my girlfriends mk5 fiesta was pouring out the res cap, and it turned out the head gasket needed done, hope it helped a bit

[phil w]

Lee I would say it's the temp sensor mate , because all you are describing doesn't show any signs of actualy overheating just a high temp reading which to me is false ,
Water will swell out of the header tank as the sytem is presurised to a degree when hot, and hot water and air rise to the highest piont ,with the heater on you have the blower blowing cold air through the heater matrix ,although this is
giving hot air in doing so it is still cooling the water down as it blows through the matrix ,this is a small radiator so it is acting the same as the fan on the main radiator but nowhere as efective ,
I hope this has helped a little
Phil