Electric Fan Problems

[Lee Dutton]

I have an electric fan fitted to my 4a in front of the radiator which has been giving me some trouble as it has a thermostatic switch fitted to the bottom hose and does not have an overide switch.

The engine gets very hot before the fan cuts in and even then the fan is not great so I may fit a new unit and common sense tells me that if the fan is fitted behind the rad ie suck mode it should be more efficient as when moving there would be less restriction to air entering the front access to the rad.

I also have a thin belt conversion with alternator so do not have the original fan.

Any suggestions and recommendations on kits would be most welcome.

[AndrewMAshton]

Hello, I have the revotec kit, I went for it because I liked the brackets for fitting the fan behind the radiator, it is very efficient, I replaced a kenlowe fan which ran for ages once it started, the revotec runs for far less time, Andrew

[pfenlon]

I have an electric fan fitted to my 4a in front of the radiator which has been giving me some trouble as it has a thermostatic switch fitted to the bottom hose and does not have an overide switch.

The engine gets very hot before the fan cuts in and even then the fan is not great so I may fit a new unit and common sense tells me that if the fan is fitted behind the rad ie suck mode it should be more efficient as when moving there would be less restriction to air entering the front access to the rad.

I also have a thin belt conversion with alternator so do not have the original fan.

Any suggestions and recommendations on kits would be most welcome.

 

 

Surely the sender should be at the top hose where the water is hottest?

 

The kenlow sucker works well and that has the sender in the top hose.

 

wont your fan fit behind the rad if you have a thin belt kit fitted? An overide switch you could fit pretty easily using the existing relay, if it has one of course.

[badshead]

I also use the Revotec fan with their custom made brackets and it works well (see pic). They can also supply an electronic fan controller for the bottom hose so you can vary the cut-in temperature but I find a 88c thermo switch is fine for most situations. I'd recommend fitting an override switch, really useful in heavy traffic etc.

 

 

 

See this thread for override switch wiring diagram http://www.tr-register.co.uk/forums/index.php?showtopic=26319

[RogerH]

Hi Lee,

does your existing fan set-up have a variable control for selecting what temp the fan actuates.

If yes, you don't really need an override switch (except for emergencies). If no - why not!!.

 

Putting the fan behind the rad will work very well. Ensure that the fan is as close to the rad core as possible.

Some kits use plastic cable tie type attachments to hold ot firmly to the rad core - these work well.

 

Look at what Revington are doshing out - some good proven stuff.

 

Roger

[Guest ntc]

Not this old one again

1/ There is not that much difference between a pusher or puller

2/ The top sensor will work however it will not allow the rad to do its job

 

And Dutts

You do not say what you are using , if you have always had overheating probs I would look elsewhere first

[Lee Dutton]

Thanks so much to all for your advices, the set up I have is a bit of a botch but has worked ok but now I am using the car more and always seem to be in jams which is a problem.The thermostat is one of the units fitted to the metal part of the bottom hose so from your comments I guess this must change and I like the neat look of the rear mounted Revotec unit so will investigate that. At the moment the thermostat is not adjustable which is not a problem but an overide is really a must.

Regards Duts

[Lee Dutton]

THANKS BADSHEAD FOR THE PICTURE, THAT IS THE SET UP I LIKE, I WILL BE LOOKING FOR THE BEST PLACE TO PURCHASE THIS UNIT.

BEST REGARDS DUTS

[BrianC]

Front-mounted Pacet fan with sensor in metal section twixt bottom hose pair works fine for me, although I do have a plastic TR6(?) engine-mounted fan as well, so the electric one only comes on when stuck in traffic or when climbing 1 in 4 hills and brings temperature back to normal very rapidly.

Would definitely have used the same (or similar) setup for Lynda's TR4A if she hadn't decided to sell it.

Edited November 12, 2010 by BrianC

[Guest ntc]

Hey Duts

It is your money only trying to help and no need to shout

[Norfolkjohn]

Would definitely have used the same (or similar) setup for Lynda's TR4A if she hadn't decided to sell it.

 

Brian, I had a front mounted electric fan fitted to 393F shortly after getting the car but I didn't bother with a thermostat - just a manual switch. I have retained the original mechanical fan and so far have never had to switch on the electric fan

[PaulAnderson]

.... it has a thermostatic switch fitted to the bottom hose and does not have an overide switch.

 

I suggest you should check the thermostat used for switching the fan, several temperature ranges are available. And wire in an over-ride switch in case just as a stand by.

 

common sense tells me that if the fan is fitted behind the rad ie suck mode it should be more efficient as when moving there would be less restriction to air entering the front access to the rad.

 

Restriction to air flow is restriction whether it's caused by something behind the radiator or in front. If your fan is a poor design then by all means change it but the location makes no difference.

 

If you've cooling problems firstly look elsewehere such as a restricted radiator, restricted water jacket in the engine block. There's lots of entries on the forum on this subject.

 

My own electric fan, also in front of the radiator with stat in the bottom pipe and separate over-ride switch, rarely ever comes on.

Paul

[Lee Dutton]

Sorry Neil, dont want to upset anyone! Just checked prices as a matter of interest Revotec kit from them £143 complete, same kit from Moss £199?

makes you wonder doesn't it?

regards Duts

[BrianC]

Brian, I had a front mounted electric fan fitted to 393F shortly after getting the car but I didn't bother with a thermostat - just a manual switch. I have retained the original mechanical fan and so far have never had to switch on the electric fan

 

 

It seems you've done quite a lot of the work I was planning to do on that car John.

 

If you haven't already done it, I have a vent flap connecting rod and knob for the lever which I've come across whilst sorting out spares for sale. If you need them, let me have your address and I'll put them in the post - easier than getting out and opening the flap by hand when (if?) you want the heater on or need additional cooling! Also have a set of 4 Kevlar heater hoses and stainless steel pipe.

 

[Apologies for thread drift]

[MikeF]

I suggest you should check the thermostat used for switching the fan, several temperature ranges are available. And wire in an over-ride switch in case just as a stand by.

 

 

Restriction to air flow is restriction whether it's caused by something behind the radiator or in front. If your fan is a poor design then by all means change it but the location makes no difference.

 

If you've cooling problems firstly look elsewehere such as a restricted radiator, restricted water jacket in the engine block. There's lots of entries on the forum on this subject.

 

My own electric fan, also in front of the radiator with stat in the bottom pipe and separate over-ride switch, rarely ever comes on.

Paul

 

 

Agreed! I had overheating problems with my car at first. After flushing it through and renewing all the hoses that fixed it.

On switching to narrow belt and alternator I fitted electric fan. So now I have a pusher fan and steel tube mounted temp sensor switch. I have an overide switch but never use it. When selecting a tube mounted sensor switch rating, remember the temp there is 10-15C lower than at the top of the radiator, so choose accordingly, They are easy to change.

 

Mike

[Lee Dutton]

THANKS FOR ALL YOUR HELP AND ADVICE,I HAVE JUST ORDERED A COMPLETE REVOTEC KIT DIRECT FROM REVOTEC (IT IS MUCH CHEAPER THAN BUYING ONE FROM MOSS BROS)

IT SEEMS THE SUCK WITH AN ADJUSTABLE CONTROL IS THE WEAPON OF CHOICE FOR MOST.

 

REGARDS DUTS

[RogerH]

.....controlable suck, what more do you want

 

Roger