Cooling Issues

[ACT10N]

Hey guys, pretty fresh to this and would really appreciate any help anyone can give. Have 94 ABY S2 and last weekend drove it for 30 minutes normal driving. When stopped at home the coolant tank was steaming and boiling over. All oil and coolant temps were in normal range. Car was used for many long trips in the days before this with no problems. Aux rad is disconnected. Car used to run normally above 90 degrees with no issues. Is this a thermostat problem or a sign of knackered water pump? Thanks for any help anyone has
Regards, David !!!!

[Jas11n]

Sounds like it "could" be an airlock? is the aux rad removal recent?

[ACT10N]

Cooling Problem

Hi thanks for that. I have the car three months and it was disconnected over a year ago as far as im aware. Is that a matter of bleeding the system or could it run itself out?

[s2driveruk]

should be a small bolt (10mm) on the main rad, open this is slightly, run the car up to temperature with the heater on full heat and that should bleed it as far as i know.

Hope that helps,
David

[Jas11n]

There is also the bleed screw on one of the heater matrix hoses that goes through the bulkhead.
Just be VERY careful with this bleed screw as they like to seize up over time and can break.
It could also be a borked thermostat, ie it won't open.
Try the airlock route first though.

(anyone know why it's commonly stated to turn your heater to blow hot? coolant flows through the heater matrix regardless of what the control knob is set to )

Jas..

[ACT10N]

Cooling Issues

Cheers guys, help much appreciated. Is it fair to say then that these are symptoms of an air lock rather than someting more serious on an S2?

[s2driveruk]

...ditto that Jas, mine did

[s2driveruk]

only other thoughts would be head gasket, maybe a failure of the water pump or some other kind of blockage in the water circuit? Also known coolant to blow out when the expansion tank cap has failed...

Does the car drive/pull ok aside from this? nothing on the oil cap or in the header tank to suggest Mr Oil and Mr Water have had a meeting?

[Jas11n]

Cheers guys, help much appreciated. Is it fair to say then that these are symptoms of an air lock rather than someting more serious on an S2?

Depends what you mean by serious. First off airlock, second stuck shut thermostat, third blocked main rad, third "maybe" old style plastic bladed waterpump impellers all broke.
It's unlikely to be a seized waterpump. as you'd know for 100% definite if it was that.

Jas..

[ACT10N]

Cooling Issues

Definitely no sign of the headgasket throwing a wobbler anyway!Thank god!
Ok cheers for that guys, will try find time to give the bleeding a go later and i'll post up the results. Like i said, help really appreciated. Could get hooked on this bloody Forum! have a few repairs/changes to make to her and will be searching the old threads for quite a while! thanks, David

[Jamo]

Have the coolant tank sniffed. I had this on my current avant and it was the head gasket.

Would only happen when warm as it had gone on the exhaust side and it was letting exhaust gasses into the coolant.

[Acidburn]

Its a 13mm bolt on the top of the radiator as I had to slightly tighten mine yesterday when I topped the water up.

Does your fan kick in etc. I found with mine it was playing up sometimes and would use the water in the expansion tank before blowing.

Also when I bled david's car, I undone the bolt on the top of the radiator but had the expansion tank open and let the car warm up with him inside telling me when it was coming out hot and just topping up the coolant etc. It went well and got the air out the system.

[s2driveruk]

yep, level has been bang on ever since

[ACT10N]

Cooling Issues

Thanks for all the info there, will try what you said 'Acidburn' in the morning, weather was not too good for working on her today at all! Will try bleeding it as described tomorrow. It seems that there is a cool portion of piping where there shouldnt be, just coming up from the bottom of the rad whereas everything else is as it should be. Thanks again, will post results