ticky

Having just done the cam belt yesterday, re-fitted the rad and added water (slowly). Ive managed to get an air lock. Heaters blowing cold air then sometimes hot. Cannot drive the car at all as it overheats quickly.
I then let the system cool down, topped up the rad with water again, but still no joy.
I know its been done to death but could some advise the correct method of re-filling the rad without causing an air lock. Or any other sollutions?

CataIunya

Have you tried squeezing the rad pipes at each end top and bottom to force out the air ?

ticky

Yes I have tried that today but still no joy.
I left the rad cap off last night & checked the water level, seems to have gone done. So topped it up again (slowly).
This time after getting the engine up to normal temp (heater was still blowing cold air) water started to bubble/boil & come out of the expansion res (I think thats what you call it).
I just hope it not the head gaskets, I have already been there & done them 4000 miles ago for the same symtoms.
I only changed the cam belt yesterday & I cannot see how they would go again.

When I was warming up the engine just to make sure there were no air locks The temp needle would stay at normal level (middle) however when I raised the rpm to about 3000 stand still the temp needle would go pass mid way (max 3/4). I would then immediatly turn engine off, ign still on (fans stayed on). Waited for everthng to cool down & re-top up the rad with water.
So I don't know if this would cause the head gaskets to blow?

dij

Strange one.

When did you last change the thermostat?

Did this problem only start to occur after the rad was removed?

If youre still having problems,try and remove the thermostat and then run it.

ticky

Thermostat was changed prior to new head gaskets, as I thought this could be one of the problems. New thermostat fitted & old thermostat was checked by putting it in boiling water (worked fine) ?

This new problem only started after removing the rad for better access to do the timing belt. I wish I had just removed the electric fans now & leaving the rad in place.
Before the overheating problem I would usually get a few droplets of water coming through the back box on start up, possibly a bit of condensation in the exhaust system. But once the engine had warmed up, then no droplets?
Now I seem to be getting more droplets of water coming out the back box, even when the engine has warmed up. This was one of the symptons last time the head gaskets when. Water being pulled into the cylinders?
I just wanted to try other prefered methods of getting rid of an air lock.
Before I start to think of taking the engine out (yet again)

Which way does the water in the coolong system flow, does it come from the bottom hose rad (by therm) through the rad to the top hose etc.
How much of difference will it make with out the thermostat in place?

Thanks Ticky

cong

try filling the tank up and filling up and let the engine warm up and keep topping up water eventually it will fill up but im sure there is a bleed nipple somewhere hopefuly somone on here can help

ticky

Thanks Cong,

I have tried filling it up when started but it just seems to overflow as the pressure builds up or temperature.
The bleed nipple is on the botom left hand side of the rad, it is possible to get access from under neath the car, but dont want to cut my fingers off trying to open it (close by the fans) if you no what I mean.

dij

there is no bleed nipple,the tap on the bottom of the rad is to drain the coolant out of the system.
the fact that the reservoir is at the highest point in the system means that the air should come to the top itself,and no bleading should be needed.

If you remove the thermostat,then you dont have to keep waiting for the temp to rise every timre you check.

TBH,it seems like you might have a problem,poss head cracked (if the gasket was done properly).I hope im wrong.

BTW,have you checked wether the hoses are all getting hot?
Might be worth while taking out the tstat,and running it again,before you think about removing the engine.

Good luck

RaymondH

I've just drained and refilled mine to change the antifreeze and filled it up very slowly, letting the tank run right down before putting more in (for the record, the system holds 7.6 litres and I managed to get 6 in so there's 1.6 left in the engine after draining. I also kept squeezing the bottom hose as suggested above. When I started the car I kept the cap off the tank and revved the engine to about 2000 revs - the water level dropped and you could see the coolant starting to circulate so I topped it up. When the thermostat opens the tank overflows instantly (as I found out the hard way ) so put the cap back back on as soon as you feel the coolant getting warm. I ran the engine to normal temp and checked for leaks. Check the level in the tank again when cold and don't forget the level in the expansion tank - it's just in front of the battery. Hope this helps.

N500OBY

This is exactly what hapened to mine. I thought it was an air lock but just kept over heating all the time. Even when the temp guage was on half, opened the bonnet and water bubbling out the expansion bottle. Now the engines out, and found out that the head gaskets have gone. Putting it back together this weekend. A right pain in the ****. Hopefully it will last.