This is quite a long one but I wanted to get all of the relevant information
in.

Since purchasing my GT4 about a month ago I have had an overheating problem :-((
I have scoured the GT4 goups and a friend of mine (scooby owning) suggested I try here.

The car will run normally under zero or low boost, e.g. motorway at 70MPH
but if I floor it the temp gauge starts to rise rapidly.
From a warm engine and rolling start if I give it some gas (not quite
redline) through the first three gears the temp rises rapidly into the red.
When I pull over the engine appears to be venting steam from the hole at
the top of the radiator expansion tank, it also sounds like the water in the
radiator is boiling!
On top of this I am losing a lot of water, but can't find where it is going.
I don't think enough water is venting from the expansion tank as I can lose
3 pints over 40 miles with out any trace of it ??

I have had my local garage look at it while they were doing the
service/cambelt, but they said at the outset that didn't have the correct
kit to check properly, however they have checked for all external leaks
pipes etc and found nothing.

I have subsequently had a discussion with a Toyota service department who
suggested that the worse case could be a cracked head which is venting to
the exhaust, hence no visible sign of coolant loss.
I was also told that the water flow through the head of the GT4 is very
restricted, so any loss of water for however short an amount of time can
have a serious effect.
The approximate cost for removing, finding prob, replacing/fixing and
refitting could be anything between £3-4K :-((

Does any one (in the UK) have any idea if this is a reasonable amount and
any idea of what else I could look for ??
The other option was the head gasket, which I assume would provide the same
symptoms if it was venting to the exhaust ?
Can someone tell me what they have been charged to have the head gasket
replaced and whether it would be best to have Toyota do it or take it to a
performance specialist ??

If it is a cracked head, is this common ?? If so does anyone make an uprated
head that combats this. I would hate to have mine fixed/replaced only for it
to happen again :-(

If anyone has any help I would be grateful

Many Thanks for taking your time to read this

Chris

 

Sounds silly but try the rad cap and see if there is any seepage.

I'll ask a mate of mine at work who is a memeber of the GT4 owners club.


AllanB

 

 

Hi there,
I'm no expert but if it ain't leaking from the radiator or other pipe then it sounds a bit like it's being consumed by the engine : cracked head or head gasket as you've suggested ? Is there any visible water in the engine bay after you've given it a hard drive ?
Fensport in Cambs might be a good first port of call : they seem to have a good reputation for working on Toyotas :
+44 (0) 1354 696968 or +44 (0) 7000 336776 or http://www.fensport.co.uk/
£3 - 4k seems extremely excessive for a head + rebuild : I don't know how much a brand new head from Toyota would cost (if it's required) but at £4k the head must be valued at about £3k !!! I'd have thought you should really be looking at £1k at worst.

Hope this helps a little.

 

Hi,

Which one is it? ie st185? I had one of these, a pipe had a little hole in it and sprayed coolant onto the turbo. Problem was it was behind the turbo so all I could see was steam.

Have you tried the gt4oc, they are based on Yahoo Groups, there is a guy on there called Ian Smith and Stewart something? who know these cars inside out.

sorry I cant be of more help

 

Any garage with an exhaust gas analyser should be able to check if the head or head gasket is playing up as this would show up quite easilly. If the head gasket had gone perfomance would normally be lower and fuel consumption would be up. If you start the car up and warm it up with the cap of the expanison tank you would normally get some bubbles in the expansion tank if the gasket has gone or head is cracked with some water in the exhaust. Also check the oil to see if there is any water or mayonaise like residue.

let me know how you get on and I'll tak to my Celica onwning friend , Martyn Jones , tomorrow.


AllanB

 

Thanks andyr
I've mailed Fensport to see if they can help.

Sorry I should have said, its a 1994 ST205 WRC

I've posted on there too, after reading about a few similar problems that aren't quite the same.

All comments or help gratefully received

Thanks
Chris

 

Did you buy from a dealer? go back if you did

Bad news that mate, first few weeks are always a nightmare when buying another motor, all the best with it but does sound like it could be the gasket, weird that temp gauge lowers tho!! what about the water pump??

 

Having only owned the car for a short time, I have no basis to make a judgement about performance, but the engine seems to be running fine, no problems starting, missing, or stuttering.

I don't think there is a coolant to oil leak i.e. no mayo.

Bought it privately :-(
However I did have an AA inspection which states, and I quote
'Coolant level is low, check for leaks' I did that, no leaks!
'Cooling system does not pressurise correctly when hot' Not being a mechanic, I thought this was just because of the low coolant...obviously not !!

Think the next step will be to get it to a garage and let them try to narrow the options as I don't have the neccessary equipment.

Will keep you posted
Thanks
Chris

 

Sounds like the AA man did pressure test the system and it wasn't sealed.

If you are lucky, it is just a hose off/split somewhere. The coolant line for the turbo is a good bet.

Also, get someone to do another pressure check and a hydrocarbons test on the cooling system. A bad case would be a head gasket gone. Or (I've heard of this before) the head just needs re-torquing.

Worse still (and I really don't hope this has happened) is that the block has cracked. The space between No.2 and No.3 is very small and it is thought the biggest stress on the block is at this point also.

Friend of mine had has go here which led to a crack in the bore of No.2. Was an engine out and rebuild with liners put in place. This didn't last long and actually required a new block.

Best bet ? Get it checked by a knowlegable independent, steer clear of the Toyota dealerships.

Good luck.

Ian