Help! Overheating - trying, failing to resolve

[RoccoGTII]

Hi,

Hopefully you guys can help! Ive got a GTII weber carb - manual choke - all 2E2 parts disconnected. Overheating when 2e2 was fixed prior and also before Jetex exhaust.

So far the car has had the following parts replaced:

* Jetex exhaust fixed from downpipe
* Weber carb
* Water pump
* Thermostate in the water pump.
* Radiator thermostate switch (fan switch)
* Flushed engine and replaced with recommended VW coolant
* Cleaned out expansion tank so all the rubbish is out.
* Distrubutor moved to correct timing

Symtoms:-

car runs well but overheats after driving for ten minutes. once you stop at lights needle movers further to the right. Car still runs ok. Get home and open the bonnet so not to burn the underside of the bonnet (foam is getting thin and paint bubbles as so hot). Feel the top radiator pipe, very hot and cannot be squeezed due to pressure in system. Feel the bottom radiator pipe going to water pump, this is very hot and cannot be squeezed. Infact all pipes and radiator very hot and untouchable - what you might expect maybe. Not loosing any water or oil. Yesterday the fan did not come on at all, maybe the fuse has blown - not had chance to check but can't see this being the real problem im trying resolve.

Can anyone suggest the obvious before I try the next few things:

* Temperature sender unit (located in the heat exchange hose connecting flang on the rear of the cylider head
* Thermo witch - (intake manifoled preheater) located on the top face of the hose connector on the spark pulg side of the sylider head.
* Radiator
* Give up and get a garage to resolve?

If I can get this fixed, then Ill get my arse down to another Scirocco meet.
Would appreciate your advice, thank you in advance.

[whatalotafun]

try replacing the thermastat and while the water is out backflush the system. make sure the rad is free of rubbish that builds up over the years.

FAILING THAT I WOULD SUSPECT A HEADGASKET GONE!

[monzajake]

As above.
Also have you topped up the water before all this started ?
If so you might have air trapped in the system. Park the car so that the front is higher than the back run engine with the filler cap loose and heater blowing on hot, you should get some water run out over the header tank, than the fan should kick in, as youve released the presure in the system. Tighten cap job done.

No promises but worth a pointer..

Hi,

Hopefully you guys can help! Ive got a GTII weber carb - manual choke - all 2E2 parts disconnected. Overheating when 2e2 was fixed prior and also before Jetex exhaust.

So far the car has had the following parts replaced:

* Jetex exhaust fixed from downpipe...wont affect
* Weber carb..wont affect, as manual choke
* Water pump..Complete water pump or the half part you can get via ebay etc ?
* Thermostate in the water pump... Have you tried the saucepan with boiling water trick to make shaw it's not faulty..wont be the first..
* Radiator thermostate switch (fan switch)...Wiring all ok making good contact ? also bridge the two wires together and see if fan then spins up..
* Flushed engine and replaced with recommended VW coolant..
* Cleaned out expansion tank so all the rubbish is out. wont affect anything if all outlets are clear running
* Distrubutor moved to correct timing wont affect, much just cause's pinking and a slightly higher temp reading.

If there is no mayo under the oil filler cap, no what so ever oil in the water or vise versa then i think it's some thing to do with what has been changed.

[whatalotafun]

i had a head gasket goon the wifes motor, no water in oil, no oil in water. but air was being pumped into the cooling system, only way to check, if you run the car to a garage they can do a simple test to check if there is exaust gases in your coolant by pluging a little bung into your coolant resevoir. cost £5/10.

[RoccoGTII]

Olla,

Always greatful for response :D

Drove car tonight and still very hot . I hate mayo, yuk!! good news i have none in mee engine. Will try the trick that monzajake suggested, if fails, ill have to take to garage. You fix one thing, then another thing goes.

I'll let you how it goes....probably get chance at the w/e.

m

[GT Matt]

With regret, it sounds like head gasket to me. When the hoses go hard, this is usually caused by the combustion gasses escaping past the head gasket itself and pressurising the system. As these gases are also extremely hot, this in turn increases the temp of the cooling system immensely. This particular type of failure would not display any type of 'mayo' whatsoever.

As suggested earlier - get a 'block test' done on your cooling system. It simply looks (or sniffs) for Carbon Monoxide in the coolant which would indicate exhaust/combustion gases present.

[RoccoGTII]

Hi Mate,
I've got some more questions now...
1. Do you reckon its due to the new exhaust being fitted too?
2. Kwik fit should have this machine i guess?
3. Whats involved in rectifying the problem?

no more questions, promise....

[Nate]

as above, it wants testing for head gasket failure. either get a garage (please note: garage, not fast fit centre) to do a sniff test, or get yourself one of the chemical test kits (you mix the chemical with coolant water and it changes colour in the presence of exhaust / hydrocarbons).

i'll stick a fiver on a h/g failure. sorry dude

[whatalotafun]

rectifying the problem would involve removing the cambelt, inlet/outlet manifolds then the head and replacing the head gasket and putting all back together.

this may sound simple, but.......(no offence intended in the next bit).......if you had to ask how to rectify it, you would probably want someone else to fix it.

although, on these cars it is quite straight forward for someone with a bit of mechanical knowhow.

probably a 3/4 hr job with all the correct tools.

[Nate]

rectifying the problem would involve removing the cambelt, inlet/outlet manifolds then the head and replacing the head gasket and putting all back together.

the head would probably want skimming too, otherwise you'd just end up having the gasket replace again a few hundred miles later

[whatalotafun]

rectifying the problem would involve removing the cambelt, inlet/outlet manifolds then the head and replacing the head gasket and putting all back together.

the head would probably want skimming too, otherwise you'd just end up having the gasket replace again a few hundred miles later

good that others are on here, cheers.

yeah in cases of over heating this is a very wise thing to do, usuaslly costs about £35/45 to have it tested and skimmed

[RoccoGTII]

Great advice and diagnosis people. Your right, I've not an idea how to replace it - wish I could watch someone changing and skimming it.

Just bought a thermo switch anyway today to replace that. Booked it into garage Friday next week to get it sorted - looks like its the head from everyone asked and whats been replaced. Can't see how I can still drive whilst its like that - hope its won't cause any damage to anything else????

Ill post the outcome to finish off this thread for future ref . . . ;)

UPDATE: got car back from garage and had radiator repalced and a faulty thermostate changed after all that. Running well. Will keep an eye on just in case the Head goes.

[RoccoGTII]

Update - Sorted the overheating issue myself.

After changing the water pump, radiator and cleaning the path of water in the entire system the problem was still there.

Then serviced the car changing the oil, plugs,filter, etc. etc. and it got slightly better.

Then looked underneath the car trying to spot gaps in installation of the Jetex exhaust. Decided to wrap some repair stuff around each join to see if it made any difference. Hey presto found the cause . The guage is now back in middle. very strange but its seems to be doing the trick.

Now I have a car than is running nicely apart from gear 1 and 2 selection issues which im trying resolve. I need for some struts in the front and back and some new wheels, then ill be happy.........................