Vectra coolant leak

[terry paget]

[/img]https://www.dropbox.com/s/ftc2fwijxqiuhw5/VECTRAleak2.jpg?dl=1[/img]
Vectra C 1.8 petrol manual
Found a puddle under this car this morning. Seems to be coming from a metal pipe beneath the thermostat, which then disappears behind the front heat shield. It's a simple joint, torx screws either end, got no excuse to leak now. Does anyone know, is it a flat paper gasket seal, or an O-ring?

[terry paget]

pic of leaking joint

[dave the builder]

looks like a flat fiber gasket ,but ,as I said before(when you replaced the wet stat), the thermostat housing is prone to cracking
especially if any fixing is over-tightened
a smear of instant gasket on the old gasket should solve a leak from the gasket
it won't solve a leak from a crack in the housing
so examine closely ,torch and magnifying glass is a help 

[Doctor Gollum]

Neither...

It's normal condensation from the aircon system. Ignore it and do something more important 

[Doctor Gollum]

Neither...

It's normal condensation from the aircon system. Ignore it and do something more important 

That said, if it's dripping down to that then it may well be the thermostat seal.

[Sir Tigger KC]

Neither...

It's normal condensation from the aircon system. Ignore it and do something more important 

Terry said he came out this morning to find a puddle.  An aircon condensation drip would have dried up overnight. 

[Doctor Gollum]

Neither...

It's normal condensation from the aircon system. Ignore it and do something more important 

Terry said he came out this morning to find a puddle.  An aircon condensation drip would have dried up overnight. 

Had a further look at the picture, hence my subsequent post

[terry paget]

Thanks for advice, gentlemen. Taste test confirms it is coolant.
Odd it should decide to leak after 11 years service; I reckon Dave could be right, that the housing has cracked. I see on e-bay I can get a thermostat for £15, or a thermostat with housing for £23. The housing assembly will involve more connections, but seems safer route to me. Any comments?

[Doctor Gollum]

Change it as an assembly

[terry paget]

www.ebay.co.uk/itm/FOR-VAUXHALL-INSIGNIA-1-6-VECTRA-C-SIGNUM-1-8-THERMOSTAT-WITH-HOUSING-SENSOR/251437585024
This thermostat and housing assembly has what looks like a coolant connection below the thermostat. I imagined it was an aircon pipe. It seems to go below the thermostat to connect with the heater input hose.

If so, that poor connection could be my coolant loss.

[Doctor Gollum]

www.ebay.co.uk/itm/FOR-VAUXHALL-INSIGNIA-1-6-VECTRA-C-SIGNUM-1-8-THERMOSTAT-WITH-HOUSING-SENSOR/251437585024
This thermostat and housing assembly has what looks like a coolant connection below the thermostat. I imagined it was an aircon pipe. It seems to go below the thermostat to connect with the heater input hose.

If so, that poor connection could be my coolant loss.

If, as that link suggests, the housing is plastic, I would be inclined to change the whole assembly as the plastic is likely to be getting brittle, and therefore leaky

[terry paget]

The thermostat housing is indeed plastic, thus prone to cracking if screws are overtightened.

My theory is that the thermostat housing does not need changing. The leak is the junction between the heater pipe from the block at its connection to the base of the thermostat housing. Do you agree?

[Doctor Gollum]

Not necessarily, that pipe flange could be below the leak...

[dave the builder]

The thermostat housing is indeed plastic, thus prone to cracking if screws are overtightened.

My theory is that the thermostat housing does not need changing. The leak is the junction between the heater pipe from the block at its connection to the base of the thermostat housing. Do you agree?

as I said before(when you replaced the wet stat), the thermostat housing is prone to cracking
especially if any fixing is over-tightened
a smear of instant gasket on the old gasket should solve a leak from the gasket
it won't solve a leak from a crack in the housing
so examine closely ,torch and magnifying glass is a help 

we can't remote examine where the leak is Terry
you can get the housing off and physically look at it 

[terry paget]

Or maybe you think that a crack in the thermostat housing is the cause of the leak in the heater pipe junction. So the cure is to change the thermostat housing.