It all got a bit warm...

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jas025
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Sun Aug 02, 2015 10:42 am

Yesterday I ventured south of the river once more to see my osteopath and then came back through the blackwall tunnel hitting the usual backlog which was back to the sun in the sands roundabout.

I've previously replaced thermostat, blue and brown sensors and fan switch but the car got really warm as we sat in the traffic. The gauge is pretty good, sitting normally round the mid point or a little below but when it gets a bit warmer it has a habit of dancing about. It seems to jump up a section and then sometimes come down again. It never quite got in the red zone but got far too close for my liking.

I've read that there's some nut on the back of the instrument panel that often needs tightening and also that the service indicator batteries can do strange things when they're knackered. I've seen the rev counter dance about with the ignition off before and someone has said that this is the SI batteries so I'm planning on replacing those in the near future.

My question is - does the instrument panel have anything to do with when the fans cut in or is that separate? With the temperature gauge nut needing tightening then can I believe what it's saying at all once it gets above a certain temperature?

Thanks in advance as always.
DanThe
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Sun Aug 02, 2015 11:04 am

If you have never replaced the viscous fan then that would be my first job, radiator also.

Fan switch? Does your car have air con?
jas025
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Sun Aug 02, 2015 2:39 pm

The car does have air con and it's an electric fan.
DanThe
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Sun Aug 02, 2015 8:58 pm

Does that mean you have removed the viscous fan? If so then that will be the problem
jas025
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Sun Aug 02, 2015 10:22 pm

I've not removed the fan. Car is a 92J 325i auto with factory air con.
jas025
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Sun Aug 02, 2015 10:51 pm

So I reread the wiki and it says that all e30s have the viscous - I had it with a mechanic and he said that it had an electric fan so I'd discounted issues with the viscous coupling. I'll do the newspaper test on it and have another look.

Apologies for being a complete numb nuts on this.
daimlerman
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Mon Aug 03, 2015 7:47 am

The fan that you are looking for is on the engine side of the radiator and is surrounded by a plastic shroud.
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jas025
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Mon Aug 03, 2015 4:07 pm

Thanks - I'll have a look at this this week.
jas025
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Mon Aug 03, 2015 10:20 pm

So there is an electric fan but it's the one in front for the AC behind the bumper.

Coolant level is fine so ran the car for a fair while and let it get to temperature. Did the newspaper test on the fan while cold and then again when warm. The car didn't really get much above the mid mark but when it got a little hotter the gauge started to dance about a bit up to 3/4 and then came down after. The secondary fan kicked in on the front periodically but the main one didn't feel like it got any quicker. The newspaper test was pretty much the same hot and cold but I don't really know how hot it got due to the gauge dancing about.

Reading more in the wiki, the actual amount that it increased might not have been that much if the gauge isn't reading right so I'm going to sort out the gauge before I do anything else to tighten the nut on the back. Then I'll monitor the temperature and if it gets up to 3/4 I'll do the test again. All the time I had it running it sat around the centre but it was a cooler day today and I didn't have time to take the car anywhere.
DanThe
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Mon Aug 03, 2015 11:10 pm

The viscous is dead, the elec fan does not cut in until 91° which should not happen when parked up.
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