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hey guys,

Got more issues with my rb25det...

My car used to overheat heaps, so i got a new radiator and thermostat and since that the car was sweet with water temps around 80C on my PFC,

then one day i got home and there was white smoke coming from the rear of the motor (firewall side), it was pretty bad, it kept goin for a few mins after turning the car off, a fair bit of coolant leaked somewhere from the block (it looked like it came from the rocker cover gasket),

Now the car starts and runs weird as if itdropped a couple cylinders,

whats your thoughts on what it could be? headgasket? or am I up for a rebuild?

Cheers

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theres a coolant line running around back of the engine and a welsh plug in the rear of the head. if its not coming from there then headgasket is likely. especially if its running crap. run it with the radiator cap off and see if there are bubbles.

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theres a coolant line running around back of the engine and a welsh plug in the rear of the head. if its not coming from there then headgasket is likely. especially if its running crap. run it with the radiator cap off and see if there are bubbles.

so start it up and on a cold motor see if there are air bubbles in the coolant ?

if it is the headgasket, how much $$$ am I up for roughly ?

thnx

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I would strongly advise you not to run the car without a radiator cap. If you run the engine without the radiator cap on, all the coolant will be spooling out due to expansion of the water. You will lose all the coolant within minutes of starting the engine. Best to take it to a mechanic to get it pressure tested. That's the best way to see where the problem really is.

Edited by theponyremark
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I would strongly advise you not to run the car without a radiator cap. If you run the engine without the radiator cap on, all the coolant will be spooling out due to expansion of the water. You will lose all the coolant within minutes of starting the engine. Best to take it to a mechanic to get it pressure tested. That's the best way to see where the problem really is.

Sorry bro but don't listen to this.

This will only happen if you're coolant is at normal running temp, otherwise, you wont loose any coolant, won't burn ya etc... Do it with the engine sorta cold, if you can take the rad cap off without coolant boiling everywhere, then its safe to run the engine to check for bubbles. Bubbles in the rad means you have coolant leaking into the cylinders/air entering in the coolant system...

Side note: pretty sure one of the water lines for the turbo runs around the back of your motor, check that its all still fine and dandy.

Are you leaking coolant/oil on the ground? What does this smoke smell like?

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Sorry bro but don't listen to this.

This will only happen if you're coolant is at normal running temp, otherwise, you wont loose any coolant, won't burn ya etc... Do it with the engine sorta cold, if you can take the rad cap off without coolant boiling everywhere, then its safe to run the engine to check for bubbles. Bubbles in the rad means you have coolant leaking into the cylinders/air entering in the coolant system...

Side note: pretty sure one of the water lines for the turbo runs around the back of your motor, check that its all still fine and dandy.

Are you leaking coolant/oil on the ground? What does this smoke smell like?

Yea when i drove the car home that night, the white smoke didnt really smell it was like hardcore steam, only coolant leaked and it came out from somewhere behind the block which is also where the steam came from......

I was told $1500 to fix if its a headgasket...seems quite steep.... :S

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yeah i would imagine 1500 is fair for headhgasket if the do everything including timing belt etc .depends on brand of head gasket.i meant earlier about running without radiator cap not to be driving it around town but just start and check for bubbles. pressure test coolant system on a warm engine and see where it leaks from

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if the engines cold then you can start it with the radiator cap off and run it up to operating temp and you wont lose coolant, as long as the car isn't driven. i have done this many times. but don't drive it like that.

im in nz and my head gasket job came to just shy of 3000, that was with new water pump, cam belt, head studs and a couple other bits and pieces. i got a few quotes first and the one place i went to that had done RB25 head gaskets before told me approx 3000 and the other garages that hadn't done that engine before quoted 2000 so of course i went with 2000 but ended up costing 3000, obviously a bit more to it than some think.

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