Otter Switches

Otter Switches

Author
Discussion

NordicCrankShaft

Original Poster:

1,853 posts

130 months

Yesterday (13:54)
quotequote all
Had a bit of an issue on Thursday on the way back from Goodwood.
Car over heated, gave no warning and lost coolant.

Think it may be down to a dodgy expansion tank cap so have one already on order.
Looking through my paperwork a new otterswitch was fitted in 2022 but it was supplied by the customer to the garage whist it was being serviced, so there's no receipt for it so I can see what it was.

I would like to get another otter switch that allows my fans to cut in earlier than they aleady are, doing some reading through the Steve heath book there's mention of a switch that will let the fans cut in at 74°c. I can't seem to find anything other than the 92-87 being the lowest temp switch available to buy.

Anyone else have any ideas?

Loubaruch

1,335 posts

213 months

Yesterday (14:16)
quotequote all
Just fit an override switch to bypass the otter switch. Some owners have used the dash light switch that is redundant .

I would doubt that your expansion tank cap is the problem. The fan connectors at the radiator are prone to corrosion, also due to the high current the fans need it is not unknown for the fans relay to weld its pins to the fuse block. Check the fans fuse as well.

Belle427

10,594 posts

248 months

Yesterday (15:07)
quotequote all
I would agree, when everything is ok you should not get any overheating issues.
Start by verifying both fans cut in as they should.
Did you experience issues on the move or when stationary?

NordicCrankShaft

Original Poster:

1,853 posts

130 months

Yesterday (15:27)
quotequote all
It was really strange, no issues on the move and with about 20 seconds of sitting in traffic 15 mins after leaving goodwood it went.

Belle427

10,594 posts

248 months

Confirm fans cut in as they should first port of call really.

Loubaruch

1,335 posts

213 months

As Belle says Check the fans while stationary. Switch on the ignition and short circuit the otter switch the fans should start instantantly. If it does not start fault finding. Check if 12 volts is actually reaching the fan connectors use a 12 volt bulb connected to a good earth dont just measure with a voltmeter it can be misleading. If no volts at the fan connector check the fan fuse and relay, check relay pins, often very corroded or even welded to its socket.