Had a bit of an overheating issue with my W Reg uk turbo impreza it was rebuilt by Sheffield Subaru specialists and had brand new tripple ply stainless steel headgaskets fitted 7000 miles ago. The car runs sweet as but I noticed the rad was fooked so I replaced that bled the system up let it sit on the driveway for a good 20 mins and it was fine the temp stayed at the normal point so I went out for a blast, and it overheated! I was giving it some stick and had it on boost for most of the 'test run' when I pulled it back on the driveway it had spat the coolant out of the overflow quite alot too! The fan came on and it cooled down pretty quick which it diddnt do before I changed the rad. So at least that has improved, the bottom hose seemed to be cool and the thermostat housing was red hot as if the stat wasn't opening and letting the water through? Is that possible or does it sound like my car is well and truly shot? In a nutshell it overheats when it's on boost to be honest.

 

Bumpy bumpy

 

may want to ask admin to remove this thread or ask for them to change the tilte, stress not many people will look as you can see.
Should have titled it overheating??

Don't have a clue but may be worth trying a new stat

 

Fair does, admin can u change title to strange overheating problem please?! Got a new stat today so will fit it at the weekend and try again! Hope it's not a bloody headgasket

 

Admin don't read all threads, you will have pm one. Click on News & Announcements and pm stu @ Internet brands.

 

If part of the rad is cold, then i would have thought that the thermostat is permanently closed, ie: needs replacing.

 

Sweet I really hope that solves the problem

 

Changed the thrmostat bled the cooling system as you should, no change still overheats! Found out that one or both the heads have warped. Grim times ahead!

 

How did you find this out ? are the heads now off ?

 

I was told by the specialist that it's not the gasket that's gone as there's no oil in the water and the cars not using it it's definately down to one of the heads being warped and it's letting the boost pressure into the coolant and over pressurising it causing it to spit out of the overflow pipe. All I need now is £850...

 

Thats a shame for you mate, was just interested as i havent heard of too many heads actually being warped, ther are quite a few things that can cause ur symptoms.
Certainly not doubting your mechanic, thats not what i mean atall, they will be able to diagnose better in person than anyone over the net

Hope u get it sorted and get her rolling again lad , all the best

 

It keeps air locking due to the boost forcing the coolant out I'm presuming? I don't know I'm not a mechanic just a sprayer lol I've been down just about every other route it could be but it seems like this is the big problem here, I think the original rad caused the initial problem by not cooling the system properly but there's not really much else I can think of that would cause the problem.

 

i think you should go to a garage and ask them to do a sniffer test which will tell you 99.9% if head gaskets are gone or not ! its a blue solution poured into a tester placed over the coolant bottle , if it changes colour from blue to yellow is a clear indication of head gasket failure .

 

Hang on. The heads gaskets have 'gone' because they aren't sealing the heads to the block - boost is pressuring the coolant. When HG's go on a scoob it is very rare to fail so that oil gets into the water - or water into oil, at least 1st anyway.

If they had done a proper job replacing the HG in the 1st place they should have ensured the mating faces were flat within tolerance.

You also need to know if the overheating is either the symptom or the cause.

 

I had a split header tank which looked 100% to the eye , but the split was opening under pressure, so everything was fine , but the car was over heating like mad, and i mean severe overheating. when i discovered the problem, and sorted it there was no more overheating,

I was pulling the engine for some other maintenance and tidyup work, so i did the head gaskets as a precaution, but after savage overheating on 3 occasions , the heads were still perfectly flat,its peace of mind for me now knowing whats in there (fibre gaskets changed for Cometic MLS). I have a few mechanic friends who have seen similar situations with the EJ20

 

Also rereading your thread it seems your HGs went, they were replaced, but the cause of the overheating (blocked rad) was not replaced until 7k miles after the HGs were replaced?

If true then it seems your old rad has done the HG twice

 

That's what I'm thinking, well I hadn't had the gaskets replaced myself thaey were already done when I bought the car I replaced the rad etc once this overheating lark kicked off. Not a nice introduction to the world of the Subaru! I'm 3.5k in debt for it so I'm gna have to sell my everyday mondeo st24 to finance the repair bills! I only had the Scoob a month before it died! Sooo pissed off now! I never wanted a car as much is I did with the impreza, it's my dream car and now it's turned into a nightmare lol I don't think I'd buy another Subaru unfortunately which is a shame because other than what's gone on with it I love it to bits but I think it's gonna have to be fixed minted up and sold. Can't afford it to go **** up again.