Engine Fan always on!

[AntB]

Well - went back out to the car after it was sat on the drive for just over 2 hrs after te drive home and the engine fan was on - slowley like it is when you switch off and the engine is HOT and it runs for a few mins..

Started the car up and the fan came on at full speed.... (engine cold)

Turned off - and continued running again at slow speeds.

I have taken the Fan relay (big silver one) out of the fuse box and the fan stops - so the battery isnt dead in the morning - but wondering now what is wrong????

Is it the relay do you think - or is there something else that is at fault - wondering if this was common, not happened before tonight..

Help greatly appreciated

Anthony

 

[AntB]

Upon reading here - wonder if it could be the thermo switch on the rad - as the slow fan never stops when the engine is off (unless I remove the Relay) - or does that mean its the relay - oh I dont know.... HELP!! grrr

 

[sawood12]

Could be the thermo switch. Might be worth replacing anyway as if it isn't knackered now it wont have much life left in it. There has been some debate as to how the fans work on these cars. I was told by my indie that when the engine is running both fans will run when the temp gets high enough until such time the temp comes down and the fans switch off. However if you turn the engine off then only one fan will run to conserve battery life, so this could explain why you get the two operational speeds going on. In any case if the thermo switch fails it fails safe, so the fans will run continuously even once you've switched off your engine until the battery runs flat.

What you could do in the interim is to pull the fan relay to stop the fans from flattening your battery till you get it fixed.

 

[944 man]

The relay can/does stick on series two cars too. If its a series one car then its only likely to be the radiator switch.

 

[AntB]

would be easier if it was the relay... much easier to change

if its the rad switch - is it a coolent drain job?

Cheers

 

[sawood12]

Not a full coolant drain. All you need to do is to drain the top few inches or so of water out of the radiator as the thermo switch is located at the top right hand corner as you look down onto the engine. However the access to the switch is not great. I think I have a spare used relay in my garage that was on standby when I had my problem, but it turned out to the be switch and not the relay. I'll have a look for it today and you are welcome to it if you want to try the relay before replacing the switch.

 

[AntB]

thanks for the great help guys..

A quick trip to GT One in Chertsey this AM - and they have replaced the relay as a test and that made no difference - do rad thermo switch it is.

GT One are getting me one in for Monday and will fit it for me ehilst I wait Tuesday am... GREAT Service.... Peter @ GT One is a top bloke.

for reference if anyone is interested... My car is a 1989 2.7 Lux with AirCon, and the rad switch is a two prong not three - with one variable speed fan on the rad.

Cheers again

A

 

[Copperman05]

ORIGINAL: AntB

My car is a 1989 2.7 Lux with AirCon

Lucky b*gger[]

 

[AntB]

ORIGINAL: Copperman05

ORIGINAL: AntB

My car is a 1989 2.7 Lux with AirCon

Lucky b*gger[]

[] Ice cold too []

 

[mr brightside]

Just another quick one, when i changed the temp switch in mine i forgot to put a bowl under it to catch my antifreezed water and had to go buy some more antifreeze to avoid diluting the coolant too far.

 

[AntB]

ORIGINAL: sc0tty

As long as you keep the coolant expansion tank filler cap in place, you shoud not lose much coolant. Just top up afterwards with water, and make sure to remove any air locks from the system.

Thats exactley what GT One said - they will have the old one out and new one in within seconds so coolant loss will be a minimum...

 

[AntB]

well a update for completeness - a quick trip out at lunch - and 30 mins later sitting in GT One reading a few porsche mags - the car was done, with a new Porsche rad switch fitted... []

Fan cuts in an out as needed now - and actually turns off when the car does - or stays on until it cools as it should also []

Well chuffed - GT One come very highly recommended in my opinion... I was listening to them on the phone as I was in there room waiting - and just there general chat and knowledge on the cars as they were talking to customers was second to none - they just seem always happy to help where they can - certainly I will be using them for all things Porsche related that I will not do....

Cheers for all the help anyway people..