overheating 320i

[trickey]

hi people i have just bought my 4th e30 after trying out an e36 e34 and a e39, after problems with the e39 i got rid and got a proper beemer, it has a couple of problems though when sitting in traffic or slow moving traffic she overheats but when you get moving again its fine,and also the temp gauge doesnt move up to half way like all my other bms it sits just over the red,any help would be great cheers.

[snoops]

this was happening to my 325 its probably the viscous fan that needs replacing

[320Touring]

hi people i have just bought my 4th e30 after trying out an e36 e34 and a e39, after problems with the e39 i got rid and got a proper beemer, it has a couple of problems though when sitting in traffic or slow moving traffic she overheats but when you get moving again its fine,and also the temp gauge doesnt move up to half way like all my other bms it sits just over the red,any help would be great cheers.

if she only overheats when stationary or moving slowly, its likely to be the fan thats causing the problem.

the viscous wax clutch in them can go bad, meaning that they dont spin with enough force to draw sufficient air.

pop the bonnet, start the car and take a rolled up newspaper- hold it against the fan.

If the fan stops its damamged.

If the paper gets shredded then we need to look elsewhere for the problem!

good luck

[snoops]

yeh this was happening 2 my 325 lyk wen i tuk it for MOT it was running and started overheating and also when it was idling it started to overheat but no problems when driving,i replaced the viscous fan and its alryt now

[Brianmoooore]

Seems like you may have two faults.
The temp increase in traffic and idling is almost certainly a dud viscous fan coupling, but are you saying the gauge needle is still in the red when moving along normally?
Most E30s run with their temp gauges between the quarter mark and just over the centre mark.
First thing I would do is take out the instrument cluster and tighten the small brass nut on the back directly behind the gauge. If that doesn't help, then fit a new thermostat, and then a new brown temp sensor.

[Andyboy]

I had to fit a new viscous fan to my 730i last week. It normally sat bang in the middle of the gauge but on a cold day I noticed that at most speeds it sat just over. In traffic it was running too hot and even out on the road (A1 M) it took about 10 miles for the needle to move back down to the middle. I rang a mate and they got a new coupling in for me and when I turned up, I let the car idle for 5 minutes. The needle started to head towards 3/4 and the viscous fan was doing nothing.

One new fan coupling later, cured. As soon as the needle started to edge over the 1/2 in traffic you could hear the fan cutting in and the needle edged down again. Viscous fan are not just for traffic - anything up to 30 mph in fact.

The viscous on mine was the original 262'000 mile item from 1989 so it had a good innings!

[daimlerman]

If you still have problems after trying all of the above,the radiator core could be getting choked up.Must try a different fan coupling on mine,I dident think of that....

[trickey]

i have just fitted a new fan coupling and it has done nothing still overheats, all the pipes are getting hot the water is circulating there is no creaminess in the oil and the heater gets hot,i also flushed the radiator and put in fresh anti freeze,i thought it was maybe a faulty gauge but it did evaporate the water, help.

[Mahmood]

I had overheating problems on mine so I had Ant remove the viscous and install an electric fan.

I have also added something to the coolant from Demon Tweeks (recommended by Bharat) that reduces the chance of the car overheating. So far, so good.

[Brianmoooore]

E30s are not marginal in the cooling department by any stretch of the imagination. No need for aftermarket fans or snake oil in the coolant. Just a standard system in good order filled with good quality coolant is more than adequate for the job.
Trickey - What evidence do you have that the car is actually overheating, other than the gauge?

[trickey]

its using water as i say i thought it might just be a faulty gauge as it doesnt sit in the middle like all my other bms but when the gauge was going up i parked the car up and when i returned it had used water.its a mystery

[Brianmoooore]

Does the water boil if you take off the pressure cap?
Water loss may well be a small leak.

[trickey]

no it doesnt boil and ive checked all the pipes dont think there is a leak.

[Brianmoooore]

If it doesn't boil, then I doubt if it's overheating.
Have you tightened the gauge nut? Check a round multipin plug and socket fixed to the metalwork under the inlet manifold for corrosion.
Water leaks are not always obvious. Took me eighteen months to catch one particular water pump in the act. Radiator leaks can evapourate almost instantly, and of course, it could be a minor headgasket problem.
Has your pressure cap been replaced? (Subject of a recall a few years ago).

[trickey]

no the pressure cap is pretty old might replace that next gonna have a try at the gauge on wednesday see if that helps,

[kirils]

i blocked the viscous and it's running all the time, it' interesting of the sound it makes, the car never heats anymore... but i'm not sure how goo it is for speed over 140-150 km/h???

[daimlerman]

Sorry to seem to be on my soapbox with this,but all cars were built as Brian has said with adequate cooling.Over years of use radiators silt up,although the damn things pass water on a reverse flush and therefore we think they are OK,in fact the tubes are partly blocked and they are not passing coolant through fast enough.Radiators are on the costly side so if nothing else has worked,try a new one!!This worked for me with the Daimler V8 earlier this year,having the radiator recored solved overheating in traffic.

[Brianmoooore]

As I've posted before, radiators are a 100,000 mile service item. £100 or so gets you a nice new one.

[chief]

would i be correct in saying that the radiator fan has 2 speeds, and speeds up after a certain temperature. can this be a problem. think i may have this problem on mine. i was in horrendous traffic on the a406 last night, i knew it would of overheated but i put the heater fan on number 4 and full temp i got hot feet but not the engine.
where can the 2 speed connections be found, does anyone have a picture a good description

[Brianmoooore]

would i be correct in saying that the radiator fan has 2 speeds, and speeds up after a certain temperature. can this be a problem. think i may have this problem on mine. i was in horrendous traffic on the a406 last night, i knew it would of overheated but i put the heater fan on number 4 and full temp i got hot feet but not the engine.
where can the 2 speed connections be found, does anyone have a picture a good description

Thick you may be getting confused between the auxiliary electric fan fitted to aircon cars (which has two speeds, controlled by a two temp. thermoswitch in the radiator) and the viscous coupled mechanically driven fan, which all E30s have. This fan is either unlocked (free wheeling), or locked (turning at engine speed).
The locking mechanism and it's temp. controlled mechanism is all contained in the coupling itself. No electrics involved.

[chief]

thanks for that brian
damn i was hoping that would be the only answer as i have replaced radiator, flushed fluid added coolant checked pipes. looks i need to keep looking.