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My RB20 is pumping coolant out of itself and I've got no fking idea why. On a very short drive just now it near on filled the overflow bottle and there was bugger all coolant in the rad. The other day I took it for a decent thrash and the overflow bottle was bubbling away and pissing fluid out, the rad was pretty much dry, but the car didn't overheat or even rise in temp.

It seems like the cooling system is under way too much pressure. About the only thing I can think of that'd cause that would be blown head gasket, but there is no oil in the coolant and absolutely no smoke coming from the exhaust under load.

Is it possible to blow a hg in just the right spot to pressurise the cooling system but no have coolant enter the combustion process or would there be another reason for this?

I've tried to bleed out the air bubbles in the system using the little bolt on the front side of the inlet mani & also using the rad cap, both times it basically never stopped blowing bubbles out. Not sure if this is a clue or not to what could be happening.

Also, first time time I noticed this problem was after popping a cooler hose off when the turbo spiked to 1.5bar :D

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My RB20 is pumping coolant out of itself and I've got no fking idea why. On a very short drive just now it near on filled the overflow bottle and there was bugger all coolant in the rad. The other day I took it for a decent thrash and the overflow bottle was bubbling away and pissing fluid out, the rad was pretty much dry, but the car didn't overheat or even rise in temp.

It seems like the cooling system is under way too much pressure. About the only thing I can think of that'd cause that would be blown head gasket, but there is no oil in the coolant and absolutely no smoke coming from the exhaust under load.

Is it possible to blow a hg in just the right spot to pressurise the cooling system but no have coolant enter the combustion process or would there be another reason for this?

I've tried to bleed out the air bubbles in the system using the little bolt on the front side of the inlet mani & also using the rad cap, both times it basically never stopped blowing bubbles out. Not sure if this is a clue or not to what could be happening.

Also, first time time I noticed this problem was after popping a cooler hose off when the turbo spiked to 1.5bar :D

head gasket.. doesnt have to have oil in the coolant or smoke/steam in the exhaust.. its combustion pressurizing the coolant.. maybe when your boost spiked, it was enough to blow a hole in the head gasket.

is the car hard to start?? this can be a case of coolant in the combustion chamber and loss of compression due to it going into the coolant. pressure test the radiator.. if it drops but theres no external leaks, then its head gasket.

could also just be that your radiator cap has shat itself. however the chances that it just happened to stuff up at the same time as the cooler hose popped off would be pretty low.

i would more be leaning towards the head gasket though. i had an EA falcon as my first car and i did 2 headgaskets in it. both times it was around the time that it got a coolant leak (one time was a hole in a radiator hose, the other it blew a hole in the end tank of the radiator). both times i never had any water in the oil, or oil in the water, but it was hard to start and blew the smokey mist out the rear only when it was started after sitting for a while. in normal running it wouldn't

my money is on head gasket but i slight possibility if your turbo is water cooled is that it could be a blown gasket in the turbo between water and compressor. very slight possibility and not that many turbos are water cooled..

if it is head gasket dont drive it 2 much or you wont do 2 much good to the head or the mating face or the block either... its a day job to fix it by yourself.

if it is head gasket dont drive it 2 much or you wont do 2 much good to the head or the mating face or the block either... its a day job to fix it by yourself.

:thumbsup:

Have done about 30mins of sliding 2nd and 3rd through some quicker corners near my house after trying to fix some of the symptons described in the first post :(

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