Coolant Lost And Filling

[GT500_Racer]

Hi guys got a weird one going on with the rb25....

Its only started happening the last 2 weeks, so the car will drive fine, but on a recent long drive i saw the temp needle move pass half... alarmed me for a bit, but it came back down, odd, but when i parked, i discovered my over flow was empty filled it up an she was sweet again, temp never moved again, low on coolant i guess

SO upon inspection i have found 1 leaking hose, replaced that, and went through the system and didnt really find any other leaks besides that one.

But still doesn't account for the lost of coolant every drive, i did a quick visual check of the water pump, no signs of leaks and under the sump area, its kinda got me stumped

Once the car shuts off after a long drive over an hour on freeway, i can hear the over flow bubbling, and it over fills and pukes, than after 10 minutes i can hear the upper radiator sucking the coolant back in....

Car does not blow white smoke on start up or driving, shows no symptoms of bubbling coolant in rad or over flow, so cant be head gasket right?

are there specific hoses prone to leaking that are behind the block?

cheers guys

[ShortCircuit]

It may be worth doing a system pressure test on your car to help you narrow down where it's leaking from.

[Ben C34]

Have you bled it correctly?

[Birds]

Can easily be a headgasket (the early start of one).

Pressure test the cooling system for leaks.

Inspect inside the radiator itself for any milky deposits and have a look/smell of your oil too. The coolant is going somewhere, either leaking out or getting burned up in combustion once the engine is warm.

[GT500_Racer]

Yeah tried bleeding it 3 times, left the car warm, and cracked the bleeder open and tried the old fashion way of bleeding it through the radiator

So went for a drive, and found out that the lower rad hose isnt even remotely warm, either a blockage or most likely a faulty thermostat.

No milky deposits, im guessing the thermostat is getting stuck and causing boiling, making the radiator cap open, causing coolant to boil into the overflow resulting in the coolant lost

Fingers cross it is a faulty radiator or thermostat

cheers lads

[Gareth]

I had this exact same problem on my old rb25, couldnt find the leak but after awhile it got worse and it was the radiator, so replaced that and then not long after the heater core went and leaked coolant all over the passenger footwell.

As others have said get a pressure tester, i know own one and its great, they dont cost much from ebay. Also just keep an eye on the passenger footwell, mine took forever to dry out and even longer for the smell to go