Overheating git

[Nevin]

That's it really. Coolant is boiling pretty much immediately. Any thoughts would be appreciated.

Please say something other than gasket trouble, as I have had that done in the last two years at great cost

Ta

[Nevin]

Quinny said:

I'd start by having a look at the thermostat, if it's boiling that quick I'd guess it's failed in the closed position. Hope it hasn't got to hot, or you will be looking at head gaskets again Andy.

Will get it into the garage soonest. It hasn't got above 100, so here's hoping on the gaskets.

[GreenV8S]

If the cooling system is blowing when the engine is started from cold, that's a pretty strong clue that the head gasket has failed. You could confirm with an HC check on the coolant.

[Nevin]

GreenV8S said:

If the cooling system is blowing when the engine is started from cold, that's a pretty strong clue that the head gasket has failed. You could confirm with an HC check on the coolant.

It takes time to heat up (although not as long as usual) and I can drive it at motorway speeds with the temp needle at just below 90, but when you stop there is some fair heat there.

In fact, in ton driving on the way back it was actually fine until I stopped then as well.

[GreenV8S]

So it is genuinely overheating not just blowing gas out? Might still be HGF, but check for more obvious cooling system problems first. Is the water level correct? Do the fans come on and stay on when it gets hot?

[jsr]

Apart from when my water pump failed, i've found the only time my engine gets really hot is when the coolant level is low.

Bleed the system (loosen the nut on the radiator until coolant leaks out) then top up the coolant level.

[Nevin]

Thanks guys. Airlocks/bleeding the system did actually enter my head, so i will have to try that. Anyone know where the bleed nut is on the radiator (can't find my bible)?

Cheers

Nev

[seasider]

Nevin said:

Anyone know where the bleed nut is on the radiator (can't find my bible)? Cheers Nev

Offside top corner

[JonRB]

I have had quite a history of overheating problems with my Chimaera 500 over the years. Based on my experiences you could check for:

1. Failed thermostat / otter switch
2. Failed fan(s), which includes the fuse(s), wiring and the connectors.
3. Damaged radiator
4. Buggered pressure cap (the blue one on the expansion tank)
5. Cracked head.

I've had all of the above at various points.

It could also easily be a head gasket failure or water pump failure.

Edit: There is a procedure for bleeding the system which involves more than just the bleed screw on the rad.

>> Edited by JonRB on Monday 8th August 14:47

[Nevin]

Will just go to the garage then I think

[scared but happy]

Have you checked your fans (not just one) are running.
Antifreeze?
What is your oil pressure?
Any gunk in engine?
Is your rad matrix ok? mine was shot and needed a recore.
Where is your number plate?



Bleed procedure:-
Turn car heating to HOT.
Remove screw from swirl tank.
Remove blue cap and 1/2 fill.
Fill swirl top of thread - and watch out for an overflow, oh and use a funnel.
Loosen rad bleed screw VERY gently and do NOT remove it! wait until you have a GOOD flow (ie no air) and replace.
Top up swirl tank to top of screws - Watch out that you do not damage threads.


But heating up that fast sounds bad.