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Old 13th November 2019, 13:02   #1
Dave6
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Default Operating Temperature

Hi all. Over recent months I have had new belts, thermostat, water pump, 2 speed fan and radiator. Temp is rising to 110 in stop start traffic before high speed fan brings it down. Operates at 92-97 in free flowing traffic. Getting cool air in passenger footwell and hot in drivers. Any idea what could be causing 110 operating temp and is this a problem?
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Old 13th November 2019, 13:10   #2
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Sure you don't mean low speed fan? All fairly normal, the fan's doing it's job but your heater matrix is probably blocked.

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Old 13th November 2019, 14:40   #3
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All fairly normal, the fan's doing it's job ...
I beg to differ Mike. The slow speed fan should run well before 110 degrees is reached.
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Any idea what could be causing 110 operating temp and is this a problem?
Dave,

First of all and most importantly, your profile says that you haven't got a car. If we are to help you with any degree of accuracy you need to tell us which engine you have. This is essential information in order to diagnose cooling system problems. So please could you correct your profile straight away. Please don't tell us in a posting and leave your profile as it is. Many thanks.

To answer your question in general terms:
  • Fan resistor open circuit.
  • Air lock in cooling system.
  • Expansion tank cap seals flattened.
  • Other defect in cooling system preventing proper pressurisation.
  • K-seal.

Yes, it's a problem.

Simon
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Last edited by SD1too; 13th November 2019 at 14:43..
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Old 13th November 2019, 14:47   #4
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Sorry Simon misread the post to mean 100. Specsavers ?

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Old 13th November 2019, 16:40   #5
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2.5 V6. Cooling fans coming on at 100 and 106.in traffic. It will cool down to 92 via fans and driving. Then will go back to 105 plus when it hits traffic again. Sometimes it will go down from 105 to 92 in seconds. I've also had it sat on the driveway at home and the low speed fan at 100 soon cools it back to 92. So it seems to do this high temperature thing only whilst driving and when in lots of stop start driving.

Last edited by Dave6; 13th November 2019 at 16:47..
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Old 13th November 2019, 16:47   #6
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Quote:
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2.5 V6. Cooling fans coming on at 100 and 106. It will cool down to 92 via fans and driving. Then will go back to 105 plus when it hits traffic again. Sometimes it will go down from 105 to 92 in seconds.
So what is the problem?
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Old 13th November 2019, 21:09   #7
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Quote:
Originally Posted by Dave6 View Post
Hi all. Over recent months I have had new belts, thermostat, water pump, 2 speed fan and radiator. Temp is rising to 110 in stop start traffic before high speed fan brings it down. Operates at 92-97 in free flowing traffic. Getting cool air in passenger footwell and hot in drivers. Any idea what could be causing 110 operating temp and is this a problem?

The heat imbalance from each side of the cab heater is a sign that the matrix is silted up. A hosepipe back-flush with the inlet/outlet hoses detached from the system may well fix it.


Did the reported temperature/fan activity start when the new fan was installed? Is it an MGR fan or after-market?



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Old 14th November 2019, 08:15   #8
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Thank you for the responses. The two speed fan system is working at the correct temperatures according to the OBD so perhaps this is a pressurisation issue. I will buy a new expansion tank cap and if that doesn’t work I will get a reputable garage to refill and bleed the coolant to eradicate any possible air lock. Lots of niggly problems for what otherwise is a good car to drive.
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Old 14th November 2019, 08:43   #9
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Quote:
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The two speed fan system is working at the correct temperatures ...
Apologies for my confusion Dave. I see that you have said several times that you have a 2 speed system. Thanks for the correction.
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I will get a reputable garage to refill and bleed the coolant to eradicate any possible air lock.
I would urge you to do that yourself but if not, print the MGR procedure specifically for the KV6 and give it to them.

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Old 14th November 2019, 10:40   #10
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Did the reported temperature/fan activity start when the new fan was installed? Is it an MGR fan or after-market?
Any info on this Dave?

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