engine coolant warning light

[redmoog]

2003 vectra 1.8sri 16v.........advice needed please
enginee coolant now needs topping up every other day, level drops 1 inch or so every time. up until a week ago topup maybe 1 every 2 months
mechanic has checked this several times, gas test on engine....dye in the header tank not leaking! he suggested the only other thing could be the head gasket (gulp) but its running sweetly so dont want to spend £500 if not required!
not sure if relveant but i'll mention it anyway temp gauge doesnt move from its lowest level (hasnt done for months), had new resistor fitted 2 weeks ago as heated only work on 4, last few days only warm air blwing out
anybody else had similar problems, if so is there an easy fix!
thanks in advance
mick

[Big Dave]

mechanic has checked this several times, gas test on engine....dye in the header tank not leaking!

Did he carry out a sniff test of the coolant to see if hydrocarbons are present?

No, I don't physically mean a sniff test with his nose, but with a proper tester. That should tell you if the head gasket has gone.

Also, has he tried pressure testing the system?

[Das]

Seen a couple of post now regarding splits in the header tank so might be worth taking that off and having a good look. Does it only drop the 1 inch, if you leave it longer does it drop further? Temp gauge is an easy one, Thermostat is goosed. Is yours the vvti engine?

[bigdave1701]

It may only be a temporary fix but have you got some radweld from halfords? Drain the coolant system, fill it with fresh stuff and add the bottle of radweld. If theres a leak, it'll find it and gum it up! Its handy so far as you'll be able to follow the coolant flow and find the crusty splodge where the radweld had bubbled through a gap.

[mccluskey119]

sounds very similar to my car although the water level hasnt went down in a while now ?
I just posted in another thread about my temp gauge not moving unless idling for a while
mines isnt the vvti

[cont1204]

It may only be a temporary fix but have you got some radweld from halfords? Drain the coolant system, fill it with fresh stuff and add the bottle of radweld. If theres a leak, it'll find it and gum it up! Its handy so far as you'll be able to follow the coolant flow and find the crusty splodge where the radweld had bubbled through a gap.

However you're then left with a bottle of radweld floating round the system! I'd do that to find the leak and as soon as it was fixed, thoroughly flush the whole lot out again to get rid of any left overs.

[ChrisBilly]

I had the same, it was a small vapour leak in the corner of the radiator.
I only found the leak by looking with a torch in the dark on a cold evening with the engine hot and running. It was then easy to spot the steam coming from the rad.
And more recently I replaced the expansion tank as it developed a small leak.
I personaly wouldn't use radweld type products for fear of damaging the heater matrix.

[carpet]

If you only have warm air coming from the heater matrix and your temperature gauge is stationary I would look towards replacing the thermostate. Do not over fill the header tank as the surplus may be ejected, only fill to the mark. As Big Dave said, how about a pressure test?

[Bigtee]

Coolant pressure test is the way forward. Poke and hope and rad weld is for bodgers.

Find the leak and fix it done.

[redmoog]

thanks for the tips lads, i'll pass them on to the mechanic and let you know if he solves the problem