Cannon Fodder

iTrader: (100)

I have a problem with my MY04 Spec C which is really baffling me.

The coolant when it gets up to operating temp ie the thermostat has opened and the fans are working is being dumped into the expansion bottle.

I've bled the system through the turbo coolant hose in order to try and reduce the problem of an air lock, the heaters get warm and the coolant is circulating as well. If the car is driven on boost it'll empty the coolant in a matter of seconds.

I have carried out a hydro carbon test on the coolant which should eliminate a head gasket problem pressurising the coolant and the hoses aren't going hard either.

My thoughts are now to change the header tank and radiator caps in order to eliminate them or find fault with them.

Has anyone suffered from a similar problem and what was the cause?

And where can I source some uprated STi / HKS caps from?

jura11

iTrader: (7)

HKS distributer is here Sumo Power(i have been there few times and just look at R35 GT-R from GT series,worth drive there).
Here is few
http://www.scoobyworld.co.uk/catalog...p?keywords=cap
http://www.japanesecarimports.net/pa...pressure%20cap
http://www.grahamgoode.com/subaru/pa...em=15009-AK002
http://j-w-racing.co.uk/product.php/...m_type_2___red


Jura

P1#1015

iTrader: (14)

Drop Tim at Scoobyparts an email, always had fantastic next day service from him

prodriverules

iTrader: (52)

I got a genuine sti 1.3 bar one from subaru,£29 if i remember rightly.

A.D.Edmundson

Unfortanetly sounds like head gasket to me, but its definately worth trying a rad cap and the cheaper things first and also try a pressure test, But if it is throwing it on boost it sounds like head gasket.....

Ant

Cannon Fodder

iTrader: (100)

If it is a head gasket failed then it's not leaking any carbon gases into the coolant, there is no cross contamination of oil or coolant, it is still possible I suppose but I believe the hydro carbon test I carried out should have eliminated that.

Cannon Fodder

iTrader: (100)

Thanks, I'll have a look on Sumo's website.

I've used them before and they do offer a very good service.

I'll give my local dealer a ring, you never know they might have one on the shelf.

Cannon Fodder

iTrader: (100)

Anyone else encountered this problem?

prodriverules

iTrader: (52)

Did this problem just start up out of the blue or did you replace coolant?

Butty

iTrader: (2)

I had the exactly the same symptoms and it was the HGs.
They only leaked above 1 bar, so the sniff test didn't work as the contaminants had evaporated/degassed by the time the test was done back at base after a road run.

It took something like 7K miles and 9 months of trying everything else and emptying the expan. tank every day before it became bad enough to do a rebuild.
It never overheated but sure filled up with air through the system.

Cannon Fodder

iTrader: (100)

I had very slight coolant leak from the top radiator hose coming loose, I tightened up the hose clamp and topped up the coolant.

Everything was fine until I was about 5 miles from home, the heaters went cold so I pulled over and found the expansion bottle full of coolant, I took the bottle out and topped up the coolant into the header tank and radiator plus I added a little water which had been lost.

At first I thought air lock, tried to bleed the air lock out and thought I had succeeded but when the car is under load (ie when boosting) you can hear the coolant being dumped into the expansion bottle. It sounds almost like a bloody coffee perculator.

Like I said earlier today I did a sniffer test on the coolant when the engine was at operating temperature and the coolant is fine, I did this test twice just to make sure.

I hope that it is just the radiator cap opening and then not closing allowing the coolant to be dumped into the expansion bottle, but this is literally emptying the coolant out of the system.

If it's not the cap at fault then I'm really confused.

prodriverules

iTrader: (52)

When you found the loose clamp and filled it up,how much coolant did you need to put in the system?
It could very well be a air lock as i suffered when i rebuilt my engine recently,it took many attempts at refilling and bleeding to get it finally out of the system and i mean 7/8 go's with quite a few miles up and down the road to try and shift the air lock round and out.
I'll be honest when i say i almost got convinced it was a HG failure but turned out not to be thank god lol.
It certainly does pay to get a 1.3 bar cap as it raises the boiling point of the water as well as being new of course so id get it and also try getting the car at running temp and then turn it off and leave over night as that can allow an air lock to come out whilst cooling.

The king

Shure, tiny chance for the cap, but Ive only seen this once, and a quick inspection of the cap will reveal any faults there.. So if the spring is tight, and the gasket is fine, then you should do another test. Make shure you have good operating temperature, a good drive before the test wont hurt. Then rev it like a madman. The tough ones usually colours the water better on boost.

And reading your post above told me what you already know. Head gasket. cold heater + full ex. tank, + bubbling under load = Sorry. Do the test again.


PS

Ive been fooled by this test before. Some rev limiting, and using the clutch to build boost changed things, but only slight discolouring was seen.

wrx fifer

iTrader: (34)

i hope its not for you mate as i been through it and its a nightmare i done head gasket and it went a second time as well. very similar though kicking the coolant out etc

Cannon Fodder

iTrader: (100)

Well I have tried a new rad cap and it does look 99.99% likely that I have a head gasket failure, same symptoms as soon as any boost is used the coolant is dumped into the expansion bottle.

So what next?

Do I just renew the head gaskets and do an ARP 11mm head stud conversion or go the whole nine yards...

I'm leaning towards the above plus

Mahle forged pistons
ACL racing bearings
Uprated con rods
Exterior oil cooler
Plus a few other options yet to be decided

Bang goes my Scoobyclinic SC46 turbo, for a while anyway.

And I thought the JDM twin scroll engine were pretty much bomb proof.

eggy790

iTrader: (20)

mate, come back bigger and stronger, use it as an excuse, save the pennys and get a 2.1 cdb in their from engine tuner, and then watch how lively that sc46 will be

53

iTrader: (41)

How many miles has the car done ?

prodriverules

iTrader: (52)

Sorry to hear this mate,not good right after crimbo

ScoobyDoo69

iTrader: (17)

You haven't mixed two different types of coolant have you?

Cannon Fodder

iTrader: (100)

Thanks, I was considering a 2.1 but I really like the high revving 2.0 engine, the only extra expense really with the 2.1 is the crank and the machining required.

Just over 43,000 miles, might just be one of those things.

Cheers, I don't think that there is ever really a good time but never mind onwards and upwards.

prodriverules

iTrader: (52)

Good luck with it

Cannon Fodder

iTrader: (100)

No it has the Shell anti-freeze which Subaru supply, I had a full service on the car when I got it as the previous owner didn't service it to schedule as the timing belt was at least 18 months overdue.

The coolant system was drained and then refilled with a fresh coolant mixture.

prodriverules

iTrader: (52)

Just sound's like it was her time to go im afraid.

jura11

iTrader: (7)

Hi matey i go personally this month for 2.1 with AVCS(engine will be built Neil Case@Slowboy Racing for £2.8k),because is not worth just go for forged built and for these money you have great 2.1 stroker.Mine engine has possibly HG failure(just turn 95k) and is not that bad as yours and piston ring failure as on mine(just one piston have low compression) as well.
Good luck matey and hope you get sorted.


Jura

Sc0oby

check your waterpump first or replace the water pump before pulling apart the engine

bugeyejohn

iTrader: (11)

The pump impellers have been known to sheer of stopping the water to circulate correctly causing the same problems as you have,id check that first