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Discussion Starter · #1 ·
Whilst in a queue to get my car washed last saturday i looked down to notice my cars temperature gauage had gone about 3/4 of the way up. It has never been above 1/2 before even after hours of driving. As soon as i was moving again it came back to 1/2 way. I guess that the rad fans were not kicking in but wanted to check at what point they should. All the other cars i've ever owned never let the temp gauage get above 1/2. Also, is there away to check the fans work, can i earth the sensor or something similar so at least i can at least narrow down the problem.
 

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The Hong Kong Nutzer
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i had same problem before, but only for a little while before I (Durango Richard on here actually) found out the reason

same as you, when the car is idling it goes up to 3/4
then when it moves it goes back down to halfway

I thought it was the rad fan or water pump, however end up having a leaky heater hose and the water level inside the rad is low... hence cooling effect during idling wasnt enough resulting in slight overheating

it might be your fan of course, just want to share my experience
hope it helps

p.s. if your car got A/C, try turning it on and both fans should turn
if turns then it means your fan works

it might also be your thermostat
 

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Rollin' on 15's, baby!
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Also, is there away to check the fans work, can i earth the sensor or something similar so at least i can at least narrow down the problem.
Very easy on a 1.6 Mk1. Pull the connector off the thermo switch on top of the thermostat housing and bridge the contacts in the connector.

Not so easy on other models as the fans are ECU controlled, unless you have Air Con as already mentioned.
 

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Discussion Starter · #6 ·
Thanks for the responses. I do have aircon so will give this a try later. I hope i haven't got a leak, i do check the coolant and although the expansion bottle was a little low there was plenty in the rad (i.e full under the filler cap). The rad looks pretty new too.
 

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The Hong Kong Nutzer
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Thanks for the responses. I do have aircon so will give this a try later. I hope i haven't got a leak, i do check the coolant and although the expansion bottle was a little low there was plenty in the rad (i.e full under the filler cap). The rad looks pretty new too.
If the fan turns when you turn on the air con, it means the fan itself is working. It doesnt mean the fan kicks in at right time. You may then well check the relay and thermostat

if the coolant in expansion bottle keeps decreasing slower it may suggest something
could be a leak or some bigger problems

give it a proper check before too late
good luck
 

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Sinatra

I had this problem myself on my old mk1 it turned out to be a very small leak in the radiator so small i couldnt notice it dripping onto the road, i replaced the rad and problem went.

Not saying your problem is the rad it could be the tempreature sender unit that sits on the top of the thermostat housing. I have one in perfect working order in my box of tricks i think, if you pm me your address i can send it out in the post for you to save you spending ?20 on a new one. If you would like to try this pm me.


Cheers
Liam
 

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Discussion Starter · #9 ·
Well i finally got round to seeing what was what. To start with i stuck the aircon on. Both fans started but one was slower than the other. After a few seconds (about 10-20) they both stopped spinning but the aircon was still on. I turned the a/c off and on and only one fan came on. If i turn the car off and stick the a/c on both will spin again. So the fans work, both spin freely but i guess one motor could be more tired than the other. Then i tried to check the temp sender unit that fits into the thermostate housing. I managed to break this buy pulling it apart. I'm not too sure if the rubber above the nut had perished or what but there was just one connector inside that was soldered to a wire. I will try and get a new sender and see if that helps, but not too sure if its the fans that are knackered.
 

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There could be some sort of blockage somewhere, that is restricting the flow of water, so that the water in the block is getting too hot, but the water in the radiator is still cool hence the fans not coming on.
I would check all over for leaks and see if there is any temp discrepancy when moving, when the fans turn off what happens to the temp of the hot air from the heaters?
An old favoutite is the thermostat, thease are quite cheap and easy to change - it might be worth trying.

P.S. I had loads of weird problems with my cooling system that magically disappeared when I changed the battery!
 
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