Radiator fan not kicking in

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Mocki
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Re: Radiator fan not kicking in

Post by Mocki »

Yes change the rad switch as per link above from BW 
You upload direct from phone or pc by clicking the "big I" 
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UnsyP
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Re: Radiator fan not kicking in

Post by UnsyP »

Hi again, thanks for all the advice. I've managed to bridge the switch and the fan works. I've replaced the switch from Brickwerks also. I've blead the coolant and refilled with blue coolant. I was sat in traffic the other day and still no fan kicking in! Fuse good too. Could it be the thermostat?

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Re: Radiator fan not kicking in

Post by JeffRoo »

Hi, first things first, the anti freeze is usually pink in colour Wiki has a good spec description. If you don’t use the right anti freeze with anti corrosion properties it can be a complete engine rebuild as the head studs are actually exposed to the coolant. Check the specs. 
secondly have you tried just letting the engine idle at home to see if the fan does actually come on? You might not hear it even sat in traffic. If you are still not convinced it’s working and you are worried fit a ‘chicken switch’. A simple search in the forum will show you all you need to know and the parts to fit it. I’ve done it, but don’t leave it on for a long time. Normal operation is for the fan to run approx 30 secs. 
lastly, it might be worth changing the temp gauge sensor. This is located in the engine bay on the main coolant tank. It might be sending a false reading to the gauge. I was worried about mine last year as it seemed to be running ‘hot’ about 3/4 of the gauge. Changed the sensor this year and now it’s smack bang in the middle 😀
keep us posted

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Re: Radiator fan not kicking in

Post by Cecil »

JeffRoo wrote:
15 Jul 2020, 23:51

lastly, it might be worth changing the temp gauge sensor. This is located in the engine bay on the main coolant tank. It might be sending a false reading to the gauge. I was worried about mine last year as it seemed to be running ‘hot’ about 3/4 of the gauge. Changed the sensor this year and now it’s smack bang in the middle 😀
keep us posted 
That is the coolant level sensor.

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Mocki
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Re: Radiator fan not kicking in

Post by Mocki »

JeffRoo wrote:
15 Jul 2020, 23:51
Hi, first things first, the anti freeze is usually pink in colour Wiki has a good spec description. If you don’t use the right anti freeze with anti corrosion properties it can be a complete engine rebuild as the head studs are actually exposed to the coolant. Check the specs. 
secondly have you tried just letting the engine idle at home to see if the fan does actually come on? You might not hear it even sat in traffic. If you are still not convinced it’s working and you are worried fit a ‘chicken switch’. A simple search in the forum will show you all you need to know and the parts to fit it. I’ve done it, but don’t leave it on for a long time. Normal operation is for the fan to run approx 30 secs. 
lastly, it might be worth changing the temp gauge sensor. This is located in the engine bay on the main coolant tank. It might be sending a false reading to the gauge. I was worried about mine last year as it seemed to be running ‘hot’ about 3/4 of the gauge. Changed the sensor this year and now it’s smack bang in the middle 😀
keep us posted
Let me clarify a few things here 
the temp gauge sender is in the thermostat housing , and only sends info to the gauge , it has no bearing on the rad fan , there is no electrical nor mechanical connection , it’s not related .

the sender in the header tank is only coolant level . 

antifreeze does not have to be pink, purple or blue . The only important info here is only top up with the same colour you have in the system . 
you only need worry about the expensive pink stuff if you are confident you won’t need to be , or it won’t decide to change the coolant in a years time , it’s a rare t25 that doesn’t have coolant changes for one reason nor another inside two years, and all antifreeze is now pretty much to the same standard , gone are the days you could get the old stuff that didn’t inhibit corrosion.
i have only ever used "comma" coldmaster blue .

you will hear the rad fan running, , traffic or not , it’s only just under your feet . 
I wouldn’t expect the fan to come on at all unless you have been driving hard for two hours and then end up sitting in a que of traffic for ten mins or more . If the fad is clear and the system working , it simply gets enough cooling without that huge fan. 

please let’s have correct info , or non ! 
Steve
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Re: Radiator fan not kicking in

Post by JeffRoo »

Thanks Mocki, I bow to your knowledge  :D :ok

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Re: Radiator fan not kicking in

Post by UnsyP »

Right, well I'm off work tomorrow, so gonna keep messing, vaping and scratching my head trying to figure it out. Brickwerks said its unlikely to be a faulty switch; and I trust them with that. Having read about chicken switches, there is a switch on the dash just to the right of the steering wheel. However, it does nothing. Could this be a switch that aint connected? I love my van and I'm always trying to learn and give things ago myself; but this stuff does my head in! I'm a nurse, not a mechanic.

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Re: Radiator fan not kicking in

Post by UnsyP »

Am absolutely stumped! I know that the fan works, I've bridged the wires. I've replaced the radiator switch. I've drained and refilled the coolant. Could it be the thermostat? Wouldn't know where that is...and wouldn't know where to start! Everyone has been really helpful; and although some advise is slightly different, most have suggested the same thing. However, I've just not managed to find a solution.

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Re: Radiator fan not kicking in

Post by Michael4 »

Is there a way of testing the fan switch without removal? 

I'm disinclined to go searching for traffic jams with cardboard taped over the radiator...

Also, I assume a two speed fan is a single fan with two speeds, not two fans?!

 
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Re: Radiator fan not kicking in

Post by lefty67 »

Are you sure its getting hot enough to come on?
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Re: Radiator fan not kicking in

Post by UnsyP »

lefty67 wrote:
19 Jul 2020, 20:44
Are you sure its getting hot enough to come on?

Not sure...I'm wondering whether its a stuck thermostat. God knows how I even tackle that! Zero knowledge of engines, wouldn't know where to start.

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Re: Radiator fan not kicking in

Post by UnsyP »

Right, I've replaced the fan switch for a second time. I've carried out all the advice again up to this point. Process of elimination, having placed my hand against the rad, its barely warm. This im guessing leads to a different fault. Could it be the thermostat? Maybe its stuck? I know that there's coolant in the rad as its bled and come through the blead hole at the top left. How difficult is it for any absolute amateur novice like me to change the thermostat? From what I've read, as mine is an early model, its just below/near the coolanr tank. Is it just a matter of disconnecting the hose, undoing dome bolts and removing/replacing? I'm trying not to use a mechanic and have to pay. I want to learn as I go along. Am I on the right tracks???

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Re: Radiator fan not kicking in

Post by Mocki »

Before you even think of Messina thermostst housing heckington if there is even a issue ....
get thermometer on the pipes ( ideally a infrared one to male the job easy ) before and after the thermostat , and then at the rad , I would not expect to even think of hearing my fan come on in the current ambient temperature unless I had just come to the end of a two hour 70 mph drive and then sat in traffic for ten mins immediately after 

to get it come on on the drive just idling will take a long while , there is 17l of coolant and the rad is right at the opposite end . 

you know the rad fan and switch work , is your temp gauge getting over to 3/4 often.?
 
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UnsyP
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Re: Radiator fan not kicking in

Post by UnsyP »

Mocki wrote:
21 Jul 2020, 13:31
Before you even think of Messina thermostst housing heckington if there is even a issue ....
get thermometer on the pipes ( ideally a infrared one to male the job easy ) before and after the thermostat , and then at the rad , I would not expect to even think of hearing my fan come on in the current ambient temperature unless I had just come to the end of a two hour 70 mph drive and then sat in traffic for ten mins immediately after 

to get it come on on the drive just idling will take a long while , there is 17l of coolant and the rad is right at the opposite end . 

you know the rad fan and switch work , is your temp gauge getting over to 3/4 often.?
 

Oh thanks for the prompt reply. Temp gauge is more closer to 4/5ths as opposed to 3/4s. I quite often drive to work 25 miles on the motorway, so I would normally expect it to kick in shortly after that.

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Re: Radiator fan not kicking in

Post by lefty67 »

Did the fan used to come on after your drive to work?
I wouldn't expect the fan to come on after 25miles of mway driving.
One of the only times my fan has come on was after being on the ramps with engine running for over an hour during an mot test. The other time was driving from crewe to Plymouth non stop and then queuing to get on a ferry.
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