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Electrical fan

Posted: 25 May 2017 19:22
by Monkeyzak
Someone's gave me an electric fan off their TR7. All works fine. Decided to ditch the viscous fan

Can someone recommend a controller? These things.

http://www.demon-tweeks.co.uk/Product.d ... oCZBDw_wcB

Re: Electrical fan

Posted: 26 May 2017 11:07
by Roger27TBB
Hello monkeyzak,
i´ve just doing this, but only for switching the condenser fans. I bought those kind of connector with a thermostat (for temperarture 103°F-112°F =95°C-100°C), because
my recon radiator doesn`t have the bore for the original radiator thermostat. It may be that you need a lower radiator thermostat (194°F-203°F). The diameter of the connector tube is 32mm, the switch has thread M14x1,5. I still use the viscous coupling, haven`t tested it until now but in the past it seems that it has failed because of the high motor temperature. I wont`t change to an electric fan, because i´ve still bought a new viscous
coupling. I havetn`t change it yet because the removal isn´t easy because of the aircon compressor and the previous owner welded the viscous coupling on two points to the pulley assembly.

regards Roger27TBB

Re: Electrical fan

Posted: 26 May 2017 17:16
by skertonman
Kenlowe used to do a sensor that fitted inside the top hose where it entered the radiator, with just a wire coming out of the hose where it connected to the rad outlet.

Whether they still do it I do not know, but it's another method should you need a different way to control it.

Re: Electrical fan

Posted: 26 May 2017 19:48
by sonscar
Got one in my car with 14 inch fan and seems to work ok.Steve.

Re: Electrical fan

Posted: 26 May 2017 21:32
by saabfast
skertonman wrote:Kenlowe used to do a sensor that fitted inside the top hose where it entered the radiator, with just a wire coming out of the hose where it connected to the rad outlet.

Whether they still do it I do not know, but it's another method should you need a different way to control it.


My electric fan (not Kenlowe), mounted in front of the rad, has a capillary stat which fits in the top hose like that. The capillary tube is only about 1mm and comes out into a control box which allows the operating temp to be varied. All works OK.

Re: Electrical fan

Posted: 27 May 2017 00:02
by BenTen
Hi Monkeyzak, I fitted a controller very similar to the one you showed a couple of weeks ago as the original supplied with the Kenlowe fan wasn't working. It was a probe that pushed into the rad fins. Cheap and nasty and did not last long.
This design, fitting into the bottom hose, is working well so far and just feels like a better design. Got mine from Robsport. They recommend a fused line from the ignition switch but i took direct fused power from battery so it may work independent of ignition.

Re: Electrical fan

Posted: 27 May 2017 01:04
by Hasbeen
I have twin 18" fans on the 8 set up as BenTens [Got mine from Robsport. They recommend a fused line from the ignition switch but i took direct fused power from battery so it may work independent of ignition].

This gave me a funny problem, apart from occasionally running too long after switching the engine off & flattening the battery.

When making a short stop for fuel for example, with the engine stopped & no coolant circulation, the heat sink from the engine would bring the water in the top of the radiator up to switch on temperature.

The 2 fans drew 36 amps, so when running did not leave enough power available from the battery to start the high compression 4.6L V8. I had to install a push button switch, set up to be always on, [to avoid an old forgetful fool turning them off & leaving them off] & push & hold pushed to turn off, to cut them out, to be able to start the thing.

On the viscous fan, my 7, with a new radiator & viscous fan [fitted when the aircon went in], can run all day, hard or in heavy traffic, on 100+F days with the aircon running flat out, & never gets above 3/16 on the gauge. The cooling system is entirely adequate, if in good condition.

Hasbeen

Re: Electrical fan

Posted: 27 May 2017 08:01
by BenTen
Thanks for the warning Hasbeen. I was hoping that since the controller is in the bottom hose this would not be an issue, but guess will need to monitor. I live in Scotland so overheating on a hot day is pretty rare anyway although it was nearly 29 degC yesterday. Woo hoo.

Re: Electrical fan

Posted: 27 May 2017 08:24
by saabfast
My sensor is in the top hose which was in the instructions. This senses the flow temp when the stat opens and switches the fan on if above the setting. I can also see the point of putting it in the bottom hose so if the flow through the rad does not cool sufficiently the fan switches on, but then the inlet flow will be much hotter. Not sure which is best. The temp always stays between 1/3 and just below 1/2 on the gauge, pretty much as it did with the viscous fan.

I have wired it up with a direct fused connection from the battery and with the controller operating a relay in the power feed so it is not switching a high load. I also wired in a lamp to show when it is running (not often) and an override switch in case the controller fails and the temp rises, I can switch it on manually. I tend to like a backup although it has worked fine for about 6 years now.

Re: Electrical fan

Posted: 27 May 2017 08:40
by Monkeyzak
https://robsport.co.uk/index.php/online ... mm-hose-id

Ordered this yesterday. I have a fan someone kindly gave me off their TR7

I presume it'll make the engine quieter too?

I've an auto electrician coming out to tidy up my messy and broken electrics next week so will get him to wire it in

Going to have a big push for the next couple of weeks and try get it on the road again

Re: Electrical fan

Posted: 07 Jun 2017 05:33
by UKPhilTR7
I have replaced my viscus with an electric fan that I also got from Robsport. The fan was easy enough to fit and I put this behind the rad, sitting where the viscus was removed from. I have a manual override on the dash so I can turn it on when I need too. The button to turn it on is green, to match the interior lighting scheme. I too have a controller (as per your links) that sits in the top hose. I got mine off ebay.

Reading the write up about the controller on either the bottom or the top hose, I can see the logic in both. I was thinking of moving the electric fan too the front of the rad and then fitting the viscus. Not too sure if that will be overkill though.

Mine comes on when the temperature gauge hits a needle past half and then turns off when she is running at a needle past ¼. When I spoke to Simon at Christmas, he did say that lots of people have their fan coming on too soon as the engine should be running at ½ and not ¼ to ½. This got me thinking and I will (when I get the chance) look into slightly increasing the temperature range.

When I brought the fan, I too got the cheap and nasty push in rad fin sensor. I didn't want to use this so I brought the hose style connector.

Re: Electrical fan

Posted: 07 Jun 2017 09:42
by busheytrader
I still have the S and S supplied electric fan and top hose capillary sensor from my V8 conversion in 1991. I've no idea what the brand is.

The fan is mounted as a pusher in front of the rad. The on - off switch is variable not fixed. I have it set up so that according to an infra red gun on the thermostat housing, the fan cuts in around 94c and off around 90c. I think the max available would be on at 96c and off at 92c. With a 82c thermostat the needle stays a bit above 1/4 on the temp gauge on the move. The fan only comes on when stationary or in town traffic with the gauge around 1/2.

I have the fan wired so I can run it with position 1 on the ignition key with the engine off but won't run with they keys removed. It has the facility for a manual override but I've never used it since the fan's been 100% reliable since fitted.

That capillary tube fitment in the top hose is a pain if you remove the rad or hose for flushing. The rubber hose deforms to take the tube and if the tube's not replaced back in the exact same position it will leak. I found this out the hard way last week. I reckon a unit in an Ali housing is the way to go now. Many moderns have the electric fan switch mounted on the output side of the rad instead of the input side these days. I don't know what the advantage is.

A pal of mine had viscous fan noises from his daily driver FHC back in the 90's. He was going to leave it to the weekend until the unit locked up and the fan exited through the radiator. He fitted an electric fan to his new radiator after that.

Re: Electrical fan

Posted: 08 Jun 2017 13:23
by Monkeyzak
Fan fitted with controller. I cut the hose on the bottom tube. It's wired direct to the battery until I get the spark to see it and improve it.

I think it's a revotec? Or something controller. Seems good.

Total nightmare getting the additional pulley off for the air-conditioning. It was loose but horrific getting the bolt out. Took hours.

Another job done. I think that's everything that needs done now so I can start driving it. :-). Then see what falls off next.

Re: Electrical fan

Posted: 08 Jun 2017 22:25
by UKPhilTR7
Good one. So now she is in a position to drive you can start enjoying her. Would be interested to see what point on the temperature gauge the fan kicks in and out.

At least you are prepared for more issues to rear their head. As with cars our age, you know they will come to the surface at some point :D

Re: Electrical fan

Posted: 09 Jun 2017 07:24
by Monkeyzak
The controller is adjustable. I've set it to come on at half way on the temp gauge. Not sure what temp that is. Is that right?