C_RHYS

I’m hoping someone on here will be able to shed some light on my problem. My car is a K plate WRX.

Every time my car is driven the coolant system gets pressurised.
I first noticed this when the car over heated a few months ago, while checking the coolant system I found the bottom outlet on the front of the header tank was blocked with what seemed to be Rad Weld. I changed the tank but after a while the problem returned, next I found the feed and return pipes for the turbo were both leaking a tiny little bit of coolant, so i changed the pressure clips on all of the top hoses for jubilee clips and it was ok for about a week then the problem returned. So I changed the cap on the header tank to a blitz 1 as I didn’t get a new 1 with the tank but that did no good.
Next I found that 1 of the head gaskets had gone so I had both of them changed and the heads pressure tested and skimmed.
The garage (which is owned by a friend of mine), took the car out for a long drive, about an hour, and had no probs but after I got it back the problem returned. I have now replaced most of the coolant hoses with Samco ones, except the little 1 by the manifold at the front/bottom of the engine, the small 1 by where the air con compressor sits and the 2 that go between the header tank and the rad/overflow. There are also the 2 heater matrix hoses that I haven't changed.
I killed the first engine last year and also broke the rad. The rad is one i got from eBay, new (although could well be a re-con) and the engine was a complete 2nd hand engine (about 50,000m) but when I had the head gaskets done we used the block from my old engine with the heads from the new one as my old bottom end was better, and my new heads in much better condition.

I'm starting to loose the will to live with this now, the car hasn't overheated or pushed any coolant into the overflow bottle that im aware of since the head gaskets were done. When sat in traffic jam the other week the temps did rise slowly to the point where the fans where cutting in then the temps would drop back to under 1/2 way. The car doesn't run hot when you’re driving day to day.

Any and all idea/solutions/theories welcome.
I'm going to take the rad off the car and put pressured water from the garden hose through it to see what sort of flow i get from the other end, then hot water through it to see if it gets hot all over. I'm also going to change the 2 hoses from the header tank that are still standard to silicone ones.

Sorry for the long thread and I appreciate all help that you guys can give.
Chris

AndyC_772

iTrader: (2)

Sorry mate, I don't quite see the problem - cooling systems are meant to be pressurised. Is yours actually leaking or blowing hoses off?

If the pressure is excessive, maybe all you need is a new radiator cap?

scooby88

it sounds as if the car is working how it should the car will get to temperature for the cooling fans to cut in whilst sat in traffic only need to worry if temp gauge goes into the red

C_RHYS

Thanks for the replays guys.

I didnt explain fully tho loking at it, its pressurising because there is air in the coolant system (airlocked).

|The heaters still work and the coolant still flows round the system as the thermostat is still opening (the bottom rad hose gets hot).

Chris

scooby88

un do the coolant tank cap slightly and drive round a bit all the air will come out, it just a lazy way but beats standing squeezing the hoses till all the air is out

WRX_Dazza

is the rad hot all over??

if the right hand side of the rad stays cool (as you look at it) then probably an airlock and you'll need to idle it, with the expansion cap off until warm, then whack the heater on full and top up. pumping the lower right hand hose at this point will help (keep fingers and arms away from moving bits and hot bits!!!

you will feel the top right hand side of the rad get hot, when the airlock is out! (if that is the problem..!)

good luck

C_RHYS

Cheers that sounds like it could save me some time getting this airlock out.

I need to find out how it getting in there though. I may just have to keep changing things till its all changed.

WRX_Dazza

check the thin little pipe that comes out the header tank...

my one had split near the fixing clip, a while back, i had to cut it back and reconnect it.

C_RHYS

I haven't changed those 2 hoses yet but I have got a length of silicone hosing on its way to me atm so will fit that and see what happens.

C_RHYS

Has any one had any probs with there heater matrix? im gona bypass mine to see if that fixes the prob.