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Temp Gauge Help!

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So my temperature gauge is sitting just above the half way 12 o'clock mark, so far its had a new radiator, new thermostat and water pump and new viscous coupling but still the temp gauge sits just above the halfway point?

 

Once there the temp reading doesn't fluctuate and the car never overheats. All the heater works perfectly and doesn't lose any coolant either.

 

I though I may have air on the system following the rad change but ive followed the steps online to bleed the system and i don't think its that?

 

Is there anything else that would cause it to run a little hot? or is it ok that the gauge sits just above the centre line?

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New thermostat- you said it. This one want the car to run hotter. Its the only explanation i can think off. The thermostat controls the coolant temperature.

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15 hours ago, Iain525 said:

Mine used to be bang on middle. About 5 years ago I did similar servicing and it's been just above half ever since. Not a problem IMO

 

 

hmmm, maybe nothing to worry about then? It never moves above the mark even in traffic, long journeys etc

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21 minutes ago, bm0p700f said:

New thermostat- you said it. This one want the car to run hotter. Its the only explanation i can think off. The thermostat controls the coolant temperature.

 

The only thing is it was like it before I changed the thermostat, I thought the new thermostat might resolve it but still exactly the same, really odd!

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Well you changed a good thermostat for another good one then. The temp guage may it self be faulty. In fact there may be no fault. Its not overheating.

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I know where you're coming from, when I first noticed it sitting differently I was concerned there's a problem but now don't bat an eyelid.

 

My 2nd 525i does sit bang in the middle with a new genuine BMW thermostat.  Could be ours open at a diff temp, eg 92 and OE are 88/90?

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If it's spot on all the time I wouldn't worry.

 

Mine sits just under the middle mark after replacing the radiator with a cheap Hella valueline.

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Thanks for the replies everyone.

 

I'll leave things be with it for the time being then, hopefully it should be ok as is :D

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On 4/27/2021 at 12:32 AM, dmarkovina1 said:

To be on a safe side I would use a temp measurement gun and read the temperature off the thermostat. Very handy device in cases like these. 

Ok I can probably get hold on one, does anyone know what temp it should be at once fully warm? 
thanks

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I'm not convinced point an IR thermometer at a piece of engine is going to be that realiable or useful, especially without a measurement pre thermostat change. Happy to be proven wrong!

Sent from my ANE-LX1 using Tapatalk

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11 minutes ago, Iain525 said:

I'm not convinced point an IR thermometer at a piece of engine is going to be that realiable or useful, especially without a measurement pre thermostat change. Happy to be proven wrong!

Sent from my ANE-LX1 using Tapatalk
 

 

Yeah, I'd tend to agree there. 

 

Keliuss

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7 hours ago, dmarkovina1 said:

You can read out the exact coolant temperature via OBD data, accessible in the cluster hidden menu:

 

http://mr-fix.info/bmw-e39-obc-hidden-menu-diagnostic-mode/

 

Test No 7. What does it read - when the needle points to the right? 

 

That's an E39 trick. 

 

Keliuss 

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Update....

 

so thermostat changed for a genuine bmw item and it’s still exactly the same :mellow:

 

the temp stamped on the aftermarket sensor was 82 degrees and on the bmw part 88 degrees so I’m assuming with the bmw part it will run hotter???

 

not sure where to go with it now?

only thing maybe is temperature sensor, the one that sends the signal to the gauge but I’m assuming that is working correctly as behaves as you would expect from cold??

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Don't forget the dash gauge isn't really calibrated, its an indication. So we have no idea how much hotter it's running. 

 

If you're really worried my suggestion would be a proper temp gauge fitted to monitor exactly what the water temp is. But sounds like overkill.

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