The 75 and ZT Owners Club Forums

The 75 and ZT Owners Club Forums (https://www.the75andztclub.co.uk/forum/index.php)
-   Technical Help Forum (https://www.the75andztclub.co.uk/forum/forumdisplay.php?f=11)
-   -   Operating Temperature (https://www.the75andztclub.co.uk/forum/showthread.php?t=300787)

Dave6 13th November 2019 14:02

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?

vitesse 13th November 2019 14:10

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.

Regards

SD1too 13th November 2019 15:40

Quote:

Originally Posted by vitesse (Post 2775421)
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.
Quote:

Originally Posted by Dave6 (Post 2775420)
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. :duh: 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

vitesse 13th November 2019 15:47

Sorry Simon misread the post to mean 100. Specsavers ?

Mike

Dave6 13th November 2019 17:40

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.

kaiser 13th November 2019 17:47

Quote:

Originally Posted by Dave6 (Post 2775452)
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?

Dave6 13th November 2019 17:53

It occurred to me that the temperature fluctuations were quite large and I would have thought that the slow speed fan would have kept things in check most of the time. Is it normal for the high speed fan to come on regularly in stop start traffic? I have also seen 110 which worried me a little.

T-Cut 13th November 2019 18:11

You've fitted a new 2-speed sytem in your KV6 I believe?


TC

kaiser 13th November 2019 18:13

Yes, normally the low speed fan should keep things in check. But with that, you can see 105 degrees.
I would try and clear all debris out from behind the fan motor. There most likely is quite a bit sitting in the "shadow" of the fan motor. That means no air is passing here.
How have you read your temperatures?
And how do you drive?. Coming off a highway and stopping in stop start traffic will mean a lot of pent up heat has to be released.

Dave6 13th November 2019 18:24

Yes it's a new two speed fan that is coming on at the correct temperatures according to the OBD. The issue seems to arise when it hits heavy traffic after a fast drive on a motorway or similar. If I leave the car for a couple of hours it will soon display high temperatures again particularly in stop start traffic. If I leave it overnight and then go for a leisurely drive on A roads and little stop start traffic, then it will operate at about 92-96.


All times are GMT +1. The time now is 03:14.

Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Copyright 2006-2020, The Rover 75 & MG ZT Owners Club Ltd