acstua

iTrader: (1)

as above, pretty sure i know the answer...

anyhow ive read various things on here, and kinda convinced my self my HG is going on my 26k Hawkeye STI ;|

If i get the HG replaced is it just as likely to go again, or can it be sorted and made reliable again ?
dont really wanna spend a grand on a car thats likely to go pop again so have to flog fairly quickly

GBH Motorsport have my car at the moment, and should be letting me know what the exact problem is with it (losing coolant when cars driven hard)
Really needed to get to Cornwall tomorrow, any ideas how long to change a HG?

Steve001

iTrader: (7)

its quite a big job, engine out, heads skimmed etc etc etc if it is the HG then you will need another car to go to cornwall (unless GBH M.sport employ WRC mechanics, then it will be done in half an hour ) i had mine done 20K ago no problems since it was done, but its allways in the back of my mind and i watch the temp guage like a hawk

muzzler

TonyBurns

Try PM to him..he seems really clued up regards this..

53

iTrader: (41)

I wouldn't put 2 and 2 together and make 5 until you know where the leak is coming from Could be anything from a split rad/pipe of failed pinch clip opening on expansion. HG failures that I have read about on Snet have usually been sneaky and over time rather than unexplained leaks All the best mate

acstua

iTrader: (1)

I like to get scared about stuff as im usually good at getting shafted for huge repair bills etc :/ one of my first fiestas needed a new ecu accordin to ford due to a fuel injection fault..


anyhow GBH Motorsport have come back to me

So atm they are saying the Rad has an obvious leak. Until they have fixed that they can't confirm its just that as wont keep pressure till have swapped the Rad.
He was pretty sure it is just the Rad and not HG as well, will find out at midday.

If its an obvious Rad leak why'd the other mech not see it...

...Might still get to Cornwall afterall!

53

iTrader: (41)

You never know mate that drivers side corner might have put a hairline in it ?

acstua

iTrader: (1)

ooo thats a very good point, although the water seems to be around the front passenger side
noticed a repaired crack on the front bumper under the headlight last weekend too btw :s

Must admit i was confused to how water got up onto the rad fan etc, maybe it didnt get "up" just got blown out :E

i double checked it when he said was an obvious fault, not just a maybe issue with rad, and he came back with a very obvious fault with the rad

ho hum, im sure the last mech was just not fully awake, or due to my thoughts on why/where the leak was didnt look at other options

juggers

iTrader: (1)

It could be any of the above It happend to me a few weeks back turned out to be a split hose.

Immy

53

iTrader: (41)

Splits and hairlines will throw coolant everywhere mate. This was a pinch clip fail on my classic, nothing major but looks nasty.

http://a6.sphotos.ak.fbcdn.net/hphot..._2452641_n.jpg

juggers

iTrader: (1)

Correct me if I am wrong but you will get a slight oily smell in the water bottle next to the rad if the gaskets gone?

ALi-B

iTrader: (1)

NO!

Common misconception that people keep bleating about in hearsay. Head gasket failure does not automatically mean oil-water mixing - that is only one kind of the many types of head gasket failure, and that depend on which area of the gasket fails. That being:

Failure between cylinders = loss of compression.

Water jacket to cylinder = Coolant loss, excessive cooling system pressures, hydrocarbons in cooling system, airlock, overheating and hydrolock.

External oil leakage = patch of oil on teh floor

External coolant leakage = coolant loss, maybe airlock (which will cause overheating).

Failure between oilways and water jacket = water and oil mixing.

A HG failure may result any one or combination of the above. Overheating as a result of coolant loss/air lock will often cause it to fail totally. But not always.

acstua

iTrader: (1)

touch wood, my cars never over heated
even after the few times i have "thrashed" it

i left it idling in the car park at work after a good drive around some country roads
the fan kicked in with the temp not getting much above mid point on

scooby1929

iTrader: (1)

A sniff test would tell you very quickly if it was the headgasket

ALi-B

iTrader: (1)

Chances are you're probably fine. Problem is the Impreza's temperature gauge, like many modern cars is a very poor indicator of engine coolant temp: It is not proportional to actual coolant temperature.

The coolant temp gauge will only go into the red once the engine is well and truely cooking. For some reason the mid range of the guage is calibrated for a range wide of of roughly 80 degrees and 110 degrees...only until temps get past 110degrees will it shoot over into the red. Its not gradual either...one second it will be "normal" several seconds later it'll quickly move over to the red. As soon as the temp drops a few degrees, it drop straight back down to normal again.

And that's assuming there is coolant flow - if you have airlock, the gauge will say normal, but the engine will be cooking away. The first sign of trouble is the heater stops blowing warm.


I guess the gauge's "dead spot" is to stop drivers getting overly-concerened over the temperature gauge moving around depending external air temperature and/or heater settings. Problem is it only shows overheating once the engine really is cooking. There is no inbetween "nearly overheating" like you'd get on a car from the 1980's. In many a case I've come across cars with a stuck open thermostat and rubbish heater yet still read normal on the temp gauge. But a laser thermometer reading on the thermostat housing shows the actual coolant temp is 20degrees less than what it should be - but the gauge reads no different!

F1 CJE UK

iTrader: (8)

Head gasket was one of the key factors that pushed me down the route of getting a full RCM build. Lost confidence in the car, 2.5l and the Subaru warranty so instead of getting a hatch sti I took my money to RCM.

acstua

iTrader: (1)

Just got a call back from GBH Motorsport, they are sure it was only a rad issue

All fixored and awaiting pickup

Only cost 360quid :s still cheaper than a HG issue!

SpecDscooby

Dont believe all you read about HG failures on 2.5's.....while i can agree they aren't appearing as solid as the 2.0ltr's i dont agree there is a widespread issue. Far Far more owners have no issues, than those who have had issues....All we are experiencing is the vocal folks who have had an issue. Again i do accept the 2.5 is not the engine the 2.0 was....

acstua

iTrader: (1)

well its back, had a quick trip down the A12, can still see abit of coolant coming out a t connector which is connected by a bit of pipe to the expansion tank

also noticed the levels actually on max now (exp tank), even when the engines hot
before it was right up the top when hot
im sure before it went right up when hot

no matter im going to cornwall in it in 30mins , so should be a good test

JAutos

iTrader: (5)

the lever will change when hot and cold and also its just had a radiator ond new coolant so you need to ignore what it did previosuly really as check the new level when cold and thats what you need to keep a check off as it wont have exactly the same level of coolant in now as whole system has been changed

53

iTrader: (41)

If it was over filled last time it would go right up to the top of the expansion tank

As a guide mine usually goes up by about an Inch when in use and back to level when cold

Alan Jeffery

In that case, you're going right by our door, so drop it in if you break it!

53

iTrader: (41)

^ almost worth breaking it Job done

juggers

iTrader: (1)

£360 for a rad issue you could of had a new one fitted for that much

trevsjwood

iTrader: (2)

For peace of mind it would be worth fitting a good aftermarket water temp gauge for the reasons Ali-B mentions
Trev

andythejock01wrx

One point..... no-one has answered the OP's question to date:

- Will it go again?

So if th e HG is replaced after failure on a Hawk STi is it just as likely to go in another 20k miles or should it be pretty reliable?

Does anyone have experience of this? Has anyone had 2 head gaskets go on their Hawk Sti?

No-one has commented on what causes this issue - it can't be the gasket itself?

ALi-B

iTrader: (1)

A headgasket going the second time is 90% of the time caused by not fixing the cause that made it fail in the first time round.

That cause can be a number of things - a minor leak that causes an airlock being one example. A dodgy water pump seal being another.

greatgonzo

iTrader: (1)

ALi-B if that is correct and its not the fault of a gasket, is there a common fault why there seems to be a few problems with the 2.5l ?

greatgonzo

iTrader: (1)

I read a lot on here of people having the HG replaced on the 2.5l but never anything else connected to the issue so maybe it is just a crap gasket
Also dont a lot of people have the Cosworth gasket fitted after a failure?

andythejock01wrx

Not sure. Is the cosworth gasket better? So no-one knows the cause of the failures? If it's an inherent issue, surely ther's a single common cause?

greatgonzo

iTrader: (1)

That's what im trying to find out, I have my suspicions its just the gaskets are the cosworth stronger? Do uprated head bolts make a difference?