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Old 17th April 2021, 17:19   #1
bilsan330
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Default Electric Fan not working.

Hi Guys....from my post a couple of weeks back re overheating and the fan blade thats come off...well I have put it all back together now and tested the electric fan, it works ok.

But now I need to get it going when the engine gets hot because it does not kick in...which could be the problem of the overheating

So its going to be some sort of electric/senor fault..

Can you suggest where to start... what would be the best part to replace first.

Thanks

Bill waiting for my second jab.
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Old 17th April 2021, 17:28   #2
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Have a look at this checklist from Jules it may be of help.

https://www.the75andztclub.co.uk/for...ight=jules+fan
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Old 17th April 2021, 18:09   #3
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Can you suggest where to start... what would be the best part to replace first.
Hi Bill,

Let's see if we can make sure that you only have to buy one part, the right one! To do this we need to gather information and do some thinking.

You say that your fan does not run when the engine gets hot. What is "hot"? Your fan should not trigger until the coolant reaches 104˚C. Have you activated the instrument pack digital temperature display to see if your engine is achieving that temperature?

How did you test the fan? Have you carried out the "demist test"?

Simon
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Old 17th April 2021, 20:16   #4
bilsan330
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Default Electric fan

Yes carried out a demister test fan motor works fine...and no I have not checked the temp yet on the gauge.
But because the car is now on sorn I can only run it on my drive even so after about 20 mins and dont forget the car is stationery I would have thought the fan would come on like in heavy traffic,,,,It was working up to about 4 months ago.
The other issue I dont understand is the water pipes around the engine seem to be hot...but when I take the water cap off ( I know slowly) the water in the reservoir is only luke warm...
lastly...what sensors would you suggest I need to replace can you name them

Thanks

Bill
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Old 17th April 2021, 21:04   #5
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The other issue I dont understand is the water pipes around the engine seem to be hot...but when I take the water cap off ( I know slowly) the water in the reservoir is only luke warm.
Hello Bill. The reason for that is the header tank isn't part of the cooling circuit. It's a sort of stagnant branch that holds a small reserve of coolant and provides space for thermal expansion of what's circulating the main system. There is a small bore hose connection to the inlet manifold which provides an escape route for air in the cylinder head. That's primarily used when refilling and bleeding the cooling system. Once everything's full and air-free, there's very little if any flow to/from the header. This is slghtly different from the KV6, which seems to have more propensity to pump coolant though the head bleed hose. In all cases, the header contents will eventually warm up through heat conduction up the connecting hose to the main system. Note that the hoses attached to the header tank are considerably smaller in diameter than the main circuit ones. That tells you they don't form part of the main cooling system. In short, what you observe is normal.



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Old 18th April 2021, 06:12   #6
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Default Fan not working

Hello T Cut I find your posts very informative...so could I ask you another question regarding this problem. The fan blades came away from the spindle so obviously the fan was not working..after a great effect I have manged to put back on again securing with a screw and some glue...

The motor works in the demisting mode...but I am trying to find out why the fan does not come on..it used but stop which I think is causing the over heating problem

So heres the question......People on here have said it could be the resistor in the fan housing a sliver type...which could mean taking the whole front off again, I really dont want to do this.

Do you think it could be the resistor as the motor works ?? or should I be looking elsewhere

If I do need to replace could i fit between the blades without taking the fan off again.??

Any advise would be gratefully received.

Thanks

Bill
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Old 18th April 2021, 07:20   #7
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... I can only run it on my drive even so after about 20 mins and dont forget the car is stationery I would have thought the fan would come on like in heavy traffic ...
Hello Bill,

There's no need to worry, it won't. An idling engine isn't under load so produces far less heat than when it is propelling the car. I see no evidence that there's anything wrong with your cooling system.

You say that the "demist" test is positive so there cannot be anything wrong with your silver resistor. There's absolutely no need to take off the bumper again.

Your previous overheating problem would have been caused by the fan blades being detached from the motor. Now that you have repaired that, you should expect no further trouble.

Simon
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Old 18th April 2021, 09:00   #8
bilsan330
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Default Electric Fan

Thanks thats encouraging to know I dont have to to take the front of again.

I will post later when I can get the car out for a spin.

But a Big thanks for your reply.

Bill
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Old 18th April 2021, 10:49   #9
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HI Bill
If the silver or when it fails which it will one day, change it for a gold one, you can fit it between the blades of the fan as a couple of sections are larger than the others.

https://www.the75andztclub.co.uk/for...d.php?t=216734
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Old 18th April 2021, 16:52   #10
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Default Electric fan not working

Hi Guys....here is the latest with this fan problem

I took the car out for a little drive before I did I disconnect the temp sensor clean it and left it unconnected....started the car and the fan kicked straight away. So I am confident for the time being its not the sensor on the fan housing. would this be right ??

Drove for about 1/2 an hour temp gauge shown half way can I assume by this that the car is not overheating. ??

However for some reason the electric fan is not kicking in it normally does if the car is stationary for a time.

Could you advise how I can check or to get it working..

Thanks

Bill
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