Hey Guys,

I changed my coolant recently on my 2006 STi. Made sure all the air bubbles were cleared and I also fitted two new STi radiator caps.

Now, I've noticed when I take her for a drive the coolant seems to overflow into the resevoir bottle. Is this normal? I've checked the thermostat and this is working fine becoz the bottom hose heats up after the car gets to operating temp.

Any advice would be great.



Cheers

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MY06 STi

Sounds like air is still in the system... How exactly did you do the coolant change?

I initially filled radiator then put the cap on, then filled the top resevoir but leaving the radiator cap off. Filled the overflow bottle up to the full mark.

I ran the car with only the top resevoir cap removed until the fans kicked in. It burped during this stage eliminating the air pockets but didn't a little after the fans kicked in.

Should I redo this again?

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MY06 STi

Issue also occurs when caps don't hold the rated pressure. Albeit their Sti caps did they come off the internet, EBay in particular?

I had some issues with Zerosports ones ... Assumed after issues they were poorly made copies.

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[COLOR=Black]Liberty GT Spec B tuned 240 HP & 372 Nm at the hubs.[/COLOR] "Instead of banning high performance cars - ban low performance drivers"

I hope not. I purchsed both the STi Radiator caps from Subaru. I'm going to run my car again, top it up if need be and see if she settles. Fingers crossed!

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MY06 STi

Best way fill the system is through the coolant line coming off the turbo and into the engine. This way you will be pushing out any air that is caught up in the back of the engine. Will need a funnel to do this as it is a fairly slim line.

Did you change the thermostat at the same time?

I left the thermostat alone. Looking at the paperwork that came with the car it was changed by the previous owner.

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MY06 STi

Did anything prompt you to change the coolant? Ie issues

sounds like air in the system but honestly it could be a lot of different things causing this mate...anything from a leaky head gasket to a bad thermostat to a bad cap to a cracked hose.
if you've burped the system a few times and it still does it then i'd take it to stechnic or another reputable workshop

Well I have been through this with mine I had resigned to the fact I had a blown headgasket after I thought I bled it properly. I ended up taking it to stechnic at Cannington who picked I had the wrong pressure cap on had thermostat changed and a genuine suby thermostat but looked very old and bled it properly with a special funnel they use.

Now it has been about 4 days with a bit of on boost action it is has been fine so fingers crossed if I had gone on boost before she would overflow the coolant. The thing with mine is you drove it off boost it was fine.

Good luck Mark

Oh also they did the tk test for the headgasket on mine showed nothing...