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Over heating issues

Posted: Thu May 26, 2005 1:35 pm
by stappin
Over heating issues...

When the car is moving the Temp is fine and also when idiling at lights or in traffic. But say for instance I pull over to get fuel when I restart the engine the Temp is well up nearly 3/4 is this due to the fan being crap?

I've changed the thermostat and that hasnt helped anyideas? :cry:

Posted: Thu May 26, 2005 1:37 pm
by BrAdZ
try changing the blue temp sensor and see what that does :cool:

Posted: Thu May 26, 2005 1:38 pm
by Davenotouring
Mine used to do this, but as soon as you start the engine it shoots back down to normal. Never caused me any problems. :)

Posted: Thu May 26, 2005 1:45 pm
by Toby_Unna
as long as it drops back to somewhere near the middle fairly soon after you start driving it should be ok.

when you stop the engine when it's already hot-ish from idling or whatever, the coolant stops circulating through the radiator and in some areas (the cylinderhead) the temp will continue to increase for a while after it's switched off.

Posted: Thu May 26, 2005 3:16 pm
by Martinaston
As toby explained once the key is turned off the car is left to cook.
No auxilery fans were fitted to these old bangers back then.
I'm pretty sure this is what leads to all those cracked head units people are always on about on the zone.

Posted: Fri May 27, 2005 11:53 am
by stappin
Can anyone recommend a lecy fan to replace the existing one?

Posted: Fri May 27, 2005 11:58 am
by JoeP
Martinaston wrote:No auxilery fans were fitted to these old bangers back then.
I'm pretty sure this is what leads to all those cracked head units people are always on about on the zone.
Is it possible to retro fit one then? anyone?

Posted: Fri May 27, 2005 12:38 pm
by craigieeb
iv heard that you can actually use an electric fan from anything realy, there easy enough to fit, there is a few people on here who have done this, and im sure 1 person used a fan from an escort turbo, (cant remember his name tho :roll:

Posted: Fri May 27, 2005 1:03 pm
by Jos
Its called 'heat soak' happens to all engines to some degree, when you switch the engine off the water stops circulating, as the engine still has a lot of heat stored in the block it heats that water up resulting in a higher reading if the engine is restarted soon after. Generally nothing to worry about.

If you have a cooling problem when running normally heatsoak can be a problem as the engine gets really hot when stopped, worst case that can happen is the head or block warps slightly..which is bad.

We had a speedboat with a 3.0l engine in it that the water pump failed in, when the engine was stopped you could hear the water boiling in the block! Needless to say the engine is dead..

Posted: Fri May 27, 2005 1:38 pm
by stappin
Is a 40mm Electric fan ott or just about right?

Posted: Fri May 27, 2005 1:41 pm
by Ade
stappin wrote:Is a 40mm Electric fan ott or just about right?
it shouldnt matter if its controlled by a thermostat, or only switched on if the engine starts to get hotter than you want.

Posted: Fri May 27, 2005 1:59 pm
by Jos
stappin wrote:Is a 40mm Electric fan ott or just about right?
40mm?!

Little small I would have said.. seeing as thats 4cm :lol:

Posted: Fri May 27, 2005 2:35 pm
by stappin
Make that 40cm hahahaha :lol: I was just gonna have it running all the time to be honest unless thats gonna cause any other problems?

Posted: Fri May 27, 2005 2:40 pm
by 320Touring
stappin wrote:Make that 40cm hahahaha :lol: I was just gonna have it running all the time to be honest unless thats gonna cause any other problems?
if the engine is too cold it may overfuel all the time, leading to huge fuel bills and poor lubrication, a cold engine is not always a happy one!

Posted: Fri May 27, 2005 2:41 pm
by stappin
320Touring wrote:
stappin wrote:Make that 40cm hahahaha :lol: I was just gonna have it running all the time to be honest unless thats gonna cause any other problems?
if the engine is too cold it may overfuel all the time, leading to huge fuel bills and poor lubrication, a cold engine is not always a happy one!
Well if it's cheaper than a cracked head I'll be happy :lol:

Posted: Fri May 27, 2005 7:42 pm
by Andy_magic
If its too cold you will overfuel causing borewash. Borewash takes the oil off the bores and wears the pistons out and waters down the oil which if left for a long time will wipe out the bottom end.

Posted: Fri May 27, 2005 9:31 pm
by Brianmoooore
Electric fan won't help with heatsoak. It's the water pump stopping that's the problem, not the fan.
If you have an electric fan running after the engine has stopped, it'll just cool the water in the rad, and give the engine an even greater thermal shock when you start it up.
Get into the habit of driving gently for a mile before you stop the engine.
If you need to stop the engine immediately after caning it, say after a mororway cruise at 90+, then ley the engine idle for 30 seconds before you turn it off.

Posted: Sun May 29, 2005 9:17 pm
by stappin
FOUND THE POXY PROBLEM!!! It was the bloody belt that seems to drive everything on the front end of the m20 block it was slipping but not squealing. Tightened this bugger up and all seems well (even with a spirited 70mph+ test run).

Still cant get any hot air in the cab though. Doesnt appear to be an air lock as water comes out the screw hole on top of the thermostat when warm any ideas?

Posted: Sun May 29, 2005 9:48 pm
by Brianmoooore
You can get an air lock in the top heater pipe. Fill the header tank to the top and release the top heater pipe at the bulkhead, and let some coolant/air out before you push it back on.
Other possibility is that the electric heater control valve has jammed shut.

Posted: Mon May 30, 2005 9:50 am
by stappin
Brianmoooore wrote:You can get an air lock in the top heater pipe. Fill the header tank to the top and release the top heater pipe at the bulkhead, and let some coolant/air out before you push it back on.
Other possibility is that the electric heater control valve has jammed shut.
Is that to be done with the heater control open or shut?

Posted: Mon May 30, 2005 9:52 am
by Brianmoooore
open