Need technical Q/A then you're in the right place
Moderator: martauto
-
stappin
- E30 Zone Newbie

- Posts: 146
- Joined: Fri Mar 25, 2005 11:00 pm
Thu May 26, 2005 1:35 pm
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?

-
BrAdZ
- E30 Zone Regular

- Posts: 645
- Joined: Mon May 02, 2005 11:00 pm
- Location: Bedford/Milton Keynes
Thu May 26, 2005 1:37 pm
try changing the blue temp sensor and see what that does

-
Davenotouring
- Married to the E30 Zone

- Posts: 7962
- Joined: Mon Jan 10, 2005 11:00 pm
- Location: Cambridge
Thu May 26, 2005 1:38 pm
Mine used to do this, but as soon as you start the engine it shoots back down to normal. Never caused me any problems.


Nissan 200SX S14a - Track Slag
BMW 328i Cab - Daily Slag
-
Toby_Unna
- Boost Junkie
- Posts: 2183
- Joined: Mon Jan 10, 2005 11:00 pm
- Location: Sheffield
Thu May 26, 2005 1:45 pm
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.
-
Martinaston
- E30 Zone Addict

- Posts: 3749
- Joined: Mon Mar 14, 2005 11:00 pm
- Location: London
Thu May 26, 2005 3:16 pm
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.
-
JoeP
- E30 Zone Regular

- Posts: 461
- Joined: Wed Mar 09, 2005 11:00 pm
- Location: The Bunge, Waveney Valley, Norfolk/Suffolk border
Fri May 27, 2005 11:58 am
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?
Alpine White 325i touring
Saying 'No' to saloon and cabriolet wrongness

-
craigieeb
- E30 Zone Addict

- Posts: 4988
- Joined: Mon Jan 10, 2005 11:00 pm
- Location: In my man cave modifying... something
Fri May 27, 2005 12:38 pm
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

M50 Turbo!!!

I shall say no more

-
Jos
- E30 Zone Camper

- Posts: 1104
- Joined: Mon Jan 17, 2005 11:00 pm
- Location: Belfast
Fri May 27, 2005 1:03 pm
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..
'89 Touring - slightly rippled with a rusty underside
'94 e36 tree climber
-
Ade
- E30 Zone Newbie

- Posts: 98
- Joined: Wed Feb 02, 2005 11:00 pm
Fri May 27, 2005 1:41 pm
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.
-
Jos
- E30 Zone Camper

- Posts: 1104
- Joined: Mon Jan 17, 2005 11:00 pm
- Location: Belfast
Fri May 27, 2005 1:59 pm
stappin wrote:Is a 40mm Electric fan ott or just about right?
40mm?!
Little small I would have said.. seeing as thats 4cm

'89 Touring - slightly rippled with a rusty underside
'94 e36 tree climber
-
stappin
- E30 Zone Newbie

- Posts: 146
- Joined: Fri Mar 25, 2005 11:00 pm
Fri May 27, 2005 2:35 pm
Make that 40cm hahahaha

I was just gonna have it running all the time to be honest unless thats gonna cause any other problems?
-
320Touring
- E30 Zone Team Member

- Posts: 12316
- Joined: Fri Feb 11, 2005 11:00 pm
- Location: Glasgow (Scotland)
Fri May 27, 2005 2:40 pm
stappin wrote:Make that 40cm hahahaha

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!
-
stappin
- E30 Zone Newbie

- Posts: 146
- Joined: Fri Mar 25, 2005 11:00 pm
Fri May 27, 2005 2:41 pm
320Touring wrote:stappin wrote:Make that 40cm hahahaha

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

-
Andy_magic
- E30 Zone Camper

- Posts: 1121
- Joined: Tue Feb 22, 2005 11:00 pm
- Location: Cambridge
Fri May 27, 2005 7:42 pm
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.
-
Brianmoooore
- E30 Zone Team Member

- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
Fri May 27, 2005 9:31 pm
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.
-
stappin
- E30 Zone Newbie

- Posts: 146
- Joined: Fri Mar 25, 2005 11:00 pm
Sun May 29, 2005 9:17 pm
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?
-
Brianmoooore
- E30 Zone Team Member

- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
Sun May 29, 2005 9:48 pm
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.
-
stappin
- E30 Zone Newbie

- Posts: 146
- Joined: Fri Mar 25, 2005 11:00 pm
Mon May 30, 2005 9:50 am
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?