Electric fan installation

[Clifford Pope]

I'm with Alex on this one, since a fan must first suck in air before it can then blow it out at the other side, it will be irrelevant which side of the radiator it is mounted.

I agree, unless you are fitting the fan to a car that has a shroud to funnel the air past the fan. In that case obviously a funnel won't funnel backwards.

I have a Mark 1 with the fan in front of the radiator. I did have to make a small cut-out slice from the cross-panel under the radiator, to clear the fan surround. Probably that would have been unnecessary with a slightly smaller fan.
I haven't noticed any loss of efficiency from that position, it easily maintains the correct temperature, only ever cutting in in slow traffic or a very hot day climbing a hill.

I agree a relay is a good idea to isolate the warning light. On another vehicle the light used to glow so brightly it was pointless as an indicator that the fan had cut in.

[Alan Chatterton]

So, if I fit a fan between the grill and the radiator (ie not engine side of rad) should I use a blow or suck one?

[Richard B]

I got confused about this to, but;

The curved bladed fans with the surrounding ring work more efficiently when rotating in one direction than the other.

Fit it in the engine bay and you want it to suck the air through the radiator.

Fit it to the other side and if you do not change anything else, it will still suck through the radiator; but from the engine bay out through the grill. When the car is stationary this would be fine, however if the car is moving then the air flow will reduce or stall.

So if the fan is fitted to the front, you have to reverse the polarity of the motor to push the air. With a curved blade it does not move as much air when in reverse compared to the normal direction of rotation.


To give an example "Airflow rating: Pull = 1250cfm / Push = 1065cfm "

http://www.ebay.co.uk/itm/Stoney-Racing ... 944805794?

[David Withers]

There are two distinct types of fan geometry, depending on whether the fan is to pull or push the air through the radiator. The BMC Morris 1100 car, for example, had a 'pusher' fan whereas the normal fan on our Triumphs is the 'puller' type.

[Alec]

Hello Richard,

Kenlowe fans are either pushers or pullers, i.e. designed to suit the location. Obviously if 'robbing' fans from another vehicle the correct location must be chosen as fitted to the original donor vehicle.

Alec

[leesellars]

Blow in front of Rad
Suck Behind Rad

Simples

Lee

[Richard B]

Kenlowe fans are either pushers or pullers, i.e. designed to suit the location.

Hi Alec, agreed, but I did not buy one from Kenlowe.

So back to my original question. Has anyone fitted one behind the radiator and if so what make and size was it?

[leesellars]

Richard

Heve you got PAS. If so you wont get one in the engine bay. So you will have to Put one infront of the Rad. 14" blower from revotek £75.00 ish. Then you will need a Relay, fan switch in the Rad and a Bypass switch. Simples

lee

[Richard B]

Ah yes 2000 MkII Estate with PAS. All fitted and wired up, as I said has a double Make relay, that disconnects the warning light from the motor when switched off.

Manual override and an 88-93 switch fitted to the top of the radiator. I'll fit a lower one if it runs too hot.



Still theres hope for my PI then as that is not PAS.

[Alec]

Hello Richard,

I take it you are still not convinced that fitting the fan before the radiator is an effective location?

I would point out that the flow figures you quote earlier are not a good example. The fan may be reversible direction but to get the best when pushing the blade would need to be removed and reversed on the motor spindle, this would give the higher airflow figure when pushing. I note from the illustration that it is very similar to the current Kenlowe fan design which I have.

Alec