Radiator fan relay

richardb · Post by **richardb** » Thu Sep 13, 2007 22:15

Over recent times when the radiator fans come on, there is a mechanical noise ( its a grating type of sound) inside the car and it sounds like it is coming from the relay ( to the right of the steering wheel). Has anyone else experienced this. I guess the relay needs replacing any ideas of a supplier- Cheers

amarshall · Post by **amarshall** » Thu Sep 13, 2007 22:51

http://www.vehicle-wiring-products.eu/V ... relays.php
or
http://www.autoelectricsupplies.co.uk/product/173
or
http://www.autoelectricsupplies.co.uk/product/172

If you have twin fans you need either a twin or double make and break type.

Preference would be for the twin.

Please note - all of those linked to are 30A (or 2x15A) versions - Lotus uprated to 40A, but these seem to be difficult to source.

Markexel · Post by **Markexel** » Thu Sep 13, 2007 22:53

Its probably a faulty otter switch ,mine did it till i replaced the the switch

Its switching itself on off prematurly

Mark

barker_001 · Post by **barker_001** » Sat Sep 15, 2007 14:15

Mine is currently doing the exactly the same thing. The relay chatters as it opens or closes. I tested the relay out of the car, ramping the voltage up and down, and the operation was fine. In the car, I also shorted out the otter switch contacts, and the relay switches in and out properly. All of this points to a faulty otter switch.

Any suggestions as to where is cheapest for one of the later push-in types?

JonK · Post by **JonK** » Sat Sep 15, 2007 18:38

I have fitted a brand new fan switch on my 87 SE

It all works fine but the relay does chatter as it cuts in.

Jon

Markexel · Post by **Markexel** » Sat Sep 15, 2007 20:01

U will probably have to get one from the usual Lotus dealers

Mine was £43 back in 2000 from paul matty with gromet delivered

When i say it was turning itself on/off quickly , it was doing it when driveing with water temp being no where near switching the otter switch on .Another thing mine was doing as the relay was chattering was the fan fail light blinking faintly

Another thing u can do is short the wires going to otter switch and drive the car for a few miles wth fan permently on if it stop chattering u know its the switch
Mark

barker_001 · Post by **barker_001** » Sat Sep 15, 2007 21:14

Given what Jon says, I think maybe I'll leave mine for now. It is switching on and off at the right temperatures, just makes a bit of a racket when doing so!

My guess is that what is happening is due to the otter switch beginning to open or close slowly, while being vibrated by the engine. This causes a series of "makes and breaks" until the switch contacts reach their final position.

amarshall · Post by **amarshall** » Sat Sep 15, 2007 21:41

http://www.lotusexcel.net/phpbb/viewtopic.php?t=764

chrisw2811 · Post by **chrisw2811** » Sat Sep 15, 2007 21:53

.... and for significantly less than 43 quid as well.

dpr59 · Post by **dpr59** » Sat Sep 15, 2007 22:13

SJ quote £28 plus VAT and delivery.

And yes I need one as well............

chrisw2811 · Post by **chrisw2811** » Sat Sep 15, 2007 22:20

http://www.nfauto.co.uk/cooling_fans.htm £24.50 - cheaper even than SJ and will probably last longer than an otter switch - or change the union pipe and use the threaded fan switch?

richardb · Post by **richardb** » Thu Sep 27, 2007 23:29

thanks for all your help- it seems I need to check temperatures of operation before I replace any parts