Tips for Viscous fan removal

oh and forgot - while on eBay get yourself a serial to USB plug ;-)

Hi guys, I've just replaced the viscous fan, taken on a test drive got it to temp but still rising. Did the rolled paper test on the fan and the fan just stops. Tell me can't be 2 dud viscous fans in a row? What else is going wrong? I mean the fan doesn't even look like its going round full pelt...


Thanks

virtualme123 said:

Hi guys, I've just replaced the viscous fan, taken on a test drive got it to temp but still rising. Did the rolled paper test on the fan and the fan just stops. Tell me can't be 2 dud viscous fans in a row? What else is going wrong? I mean the fan doesn't even look like its going round full pelt...


Thanks

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New fan is knackerd where did you get it from?

I've one if you need 1 - and mine is a working one - I just removed it as I don't want it, I'd rather have electronic fans

So I got the fan from a 4x4 place down the road and removed it from a P38 they were breaking, I'm sure I can tell the guy and we can sort something out but thanks for offer Johnny. Let me just get this straight though, because you guys are saying that as the engine gets hotter the fan will go faster, so is that governed by the thermostat? Is it not possible that the thermostat isn't detecting the heat rise? Or are you saying that the very fact that the fan stops when I put the paper in it and it stops just means the fan isn't working?

Thanks again!

virtualme123 said:

So I got the fan from a 4x4 place down the road and removed it from a P38 they were breaking, I'm sure I can tell the guy and we can sort something out but thanks for offer Johnny. Let me just get this straight though, because you guys are saying that as the engine gets hotter the fan will go faster, so is that governed by the thermostat? Is it not possible that the thermostat isn't detecting the heat rise? Or are you saying that the very fact that the fan stops when I put the paper in it and it stops just means the fan isn't working?

Thanks again!

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As the engine gets hotter it heats the VISCOUS fluid in the fan. This fluid gets thicker so the fan is driven harder. It has nothing to do with the stat. If you can stop the fan on a hot engine then it isn't being driven hard enough to be effective.

virtualme123 said:

So I got the fan from a 4x4 place down the road and removed it from a P38 they were breaking, I'm sure I can tell the guy and we can sort something out but thanks for offer Johnny. Let me just get this straight though, because you guys are saying that as the engine gets hotter the fan will go faster, so is that governed by the thermostat? Is it not possible that the thermostat isn't detecting the heat rise? Or are you saying that the very fact that the fan stops when I put the paper in it and it stops just means the fan isn't working?

Thanks again!

Click to expand...

The fan itself is filled with oil as the temp get hotter the fan spins faster not to do with the thermostat the fan itself

Ok convincing replies for the fan being the issue. On another note what if the fan oil isn't getting hot enough but the rest of the engine is? Your probably going to say have I checked the top and bottom of the radiator, well yes and both are hot... Sorry just sods law that 2 fans have gone...

Tbo you say you have done rad x 2 fans I'll probably get moaned at but go for water pump and stat why keep risking it getting hot for the
Sake of an extra £70 it cost you more if you fry it sounds like most stuff is old don't take chances is my therory just my opinion

Sounds pretty reasonable advise to me.

UPDATE: So I had a friend of mine put a temp gauge on the radiator when I'd got it hot. It was definitely hot at the top but the bottom was indeed too cool. We wondered whether it was a dud radiator so I rang the company I brought it from and he seemed sure that it was just an air lock.

I ran it for a while, and been having the heating on full, and each time it seems to take longer to get too hot, and I'm sure the bottom of the radiator is getting a little warmer. Fingers crossed it will slowly get ride of more air each time I run it. I really didn't relish the idea of replacing more parts than I have too as its cost me a fortune recently and spent most of the time in my garage...

Check for the baffle as said earlier. If the whole of the radiator top is getting hot but the whole of the bottom is cooler. I would say there is no baffle in the rad. Having the heater on hot or cold makes no difference there is no flow valve in the heating system water is constantly circulated through the matrix.

virtualme123 said:

Hi guys, I've just replaced the viscous fan, taken on a test drive got it to temp but still rising. Did the rolled paper test on the fan and the fan just stops. Tell me can't be 2 dud viscous fans in a row? What else is going wrong? I mean the fan doesn't even look like its going round full pelt...


Thanks

Click to expand...

When I changed my complete cooling system I bought my fan from famous four and have had no problems in case you need to get another one.

I have a fully working viscous fan unit that I no longer use (Datatek's mod done) - let me know if you want to buy it.

Clarky130 said:

I have a fully working viscous fan unit that I no longer use (Datatek's mod done) - let me know if you want to buy it.

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Oy!! I jumped in first with that offer

he's buying my scrap before your scrap haha

When the vehicle is overheating, stop pop the bonnet and get someone to switch of the engine whilst you look at the fan. If the fan stops with only a couple of revolutions then it is ok, if it spins for several seconds then it is phoned. Alternatively when the engine is hot and running grab hold of the fan, if you end up in hospital with missing fingers then the fan is ok. The 2nd hand fan you bought is probably faulty. If you do not wish to buy a new fan coupling then carry out Datateks mod.

I know it has been a while but I finally got to the bottom of all my troubles. After changing everthing, even water pump and thermostat I got the head gasket tested and found it woefully failing.

So next project is changing the head gasket.

Thanks for all your help though.

How it was tested?

They put a chemical in the coolant system that changed colour to indicate exhaust gases present I believe.

virtualme123 said:

They put a chemical in the coolant system that changed colour to indicate exhaust gases present I believe.

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And the Hg failed due to the RAD not heating all over judging by your other post. It may not be HGF if it's a diesel could be head failure.
Everything was changed on my spares dog except the RAD including the HG. It was the RAD that caused the problem, the top got hot, the rest didn't

Did me a favour, I got it for peanuts as they owner had been told it must be the head