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Ok, I was driving home from the city today and I noticed Shaz was creeping toward the warm section of the temp gauge. Being quite a warm day I just turned the heater on full blast thinking this would help to fix the issue.

It didn't. At a set of lights (quite conveniently near a service station) I noticed a hissing sound to accompany the increasing heat. I pulled in to the servo and let it sit for a while. The hissing died soon afterwards, but there was coolant dripping onto the ground. It is coming from the driver's side of the engine near the firewall (the pool of coolant is under the driver's side of the gearbox).

After 10 minutes I took a rag and opened the radiator cap; being careful to let the pressure off gently... There was no pressure; and the radiator took close to 3 litres of coolant. Coolant was checked 3 days ago and was full at that time.

Oh feck. I couldn't feel any scaulding hot coolant when I put my hand underneath the intake plenum and round the back of the head. So, I have no idea what it could be. I was thinking the head gasket might be gone, but the coolant is gushing out, and the car still runs smoothly on 4 cylinders and there is no white residue in the exhaust tip; so it seems unlikely.

Are there any heater hoses or seals around there? I have checked the heater hoses on the pax side of the engine bay and they are dry. There is no coolant smell inside the car, and the carpet is not wet.

Any help is appreciated.

Cheers,

Boags

isn't the water pump and associated hoses in that location? rear of engine, drivers side?

There are water hoses that go into a collar behind the oil filter (sort of a ppor man's oil cooler). That's the only thing I can think of that is under there....heater hoses are on the other side...

Babalouie wrote:There are water hoses that go into a collar behind the oil filter (sort of a ppor man's oil cooler). That's the only thing I can think of that is under there....heater hoses are on the other side...

I think that is only on the 1.8

on the B6 engine there is a blanking plug around the back of the head ( opiside to the heater hose ) these have been know to cause a problem is the olde life of the B6 engine.
also remove the oil cap and check for white goo in the cam cover
if it white the the bad news is a head gasket is gone . mind you I have had temps off the gauge and my engine is still alive ( JUST)
the blanking plug is the only thing I can think of

rhysk wrote:

Babalouie wrote:There are water hoses that go into a collar behind the oil filter (sort of a ppor man's oil cooler). That's the only thing I can think of that is under there....heater hoses are on the other side...

I think that is only on the 1.8

Ah. Righty-O.

well heres a good photo, i gather it'd be that infamous black cap to the right of the green plug. it's already been dealt with on my NA6 by a past owner. all i can see on mine is a screw in it with a hose clamp.




while you were at the servo did you make sure to get some petrol?

Yep, probably either the little black cap or the gasket on the thermoswitch housing. If you can lift the coilpacks out the way you usually get a better view down there, but it is still a rotten job with the motor in the car/gearbox still attached.

The good news is the motor is probably fine, I had a stuck thermostat push all the coolant out late last year and see some very high temps on the gauge and the motor is still holding in despite numerous and severe thrashing (including a track day). Tough little buggers these B6's.

john

My money is on the blanking cap. Engine should be OK.

The fact the coolent is on the outside is good news Geoff.

Its not the head gasket although if it got too hot it could cause it to blow.

My bet is that stupid water house at the back of the head.

Best thing to do is fill it full of water, run it till its hot and have a look.

Neil

Or fill it with water and take it (gently with cap loosened) to a radiator place and get it pressure tested.

Or buy a pressure pump and test it yourself.

(but that's dodgy )

Check your petrol guage Boagsy?

but on a more serious note.......doesn't the engine need to come out for that?

It can be done in the car - a bit awkward though.

check the sidetanks for leaks.(i think that's what its called)

i remember my nissan had a similar problem and would hiss as well.

I think your engine will be fine. My bet's also on either the blanking plug or the hose at the back of the engine.

Other than that there's only the 2 heater hoses back there.


Jules