anyone bought/fitted new otter switch in rad? help needed

[sprevett]

does anyone know part number/supplier of an otter switch?

hard to see it but it feels like a screw-in nut type item so I assume you simply unscrew old one and fit new one, perhaps with a gasket/sealant?

can it be done with bonnet on?

[jmorgan]

Clamps in. Two clips hold a plate over the rear of the switch and this is held in a rubber seal. Sod to get at.

When I took the rad to a Serck dealership for a quote on a re core, they reckoned the switch was off the shelf and the seal. But I did not need them at that time.

Edit. Think I found it easier with the bonnet off, doesn't take long. I have since had it sealed up and use a different method for the temp sensor now.

Edited by jmorgan on Tuesday 30th March 11:57

[rev-erend]

It's almost impossible to get at with the rad inplace.

As has been said - it is a rubber seal and the otter is somehow cliped in .. weird thing when you see it.

Honestly the best idea is to seal it up completely and either get a new top steel pipe and have that converted to contain an otter switch (Richard Thorpe) and ACT will probably be able to have this done.. or use an otter which can be put in the top pipe near the rad..

Kenlowe or Revotec do these.. and these are temp adjustable.

Edited by rev-erend on Tuesday 30th March 12:06

[sprevett]

good advice methinks....have just found/ordered the adjustable otter swicth replacement kit from Mod-Wise. Looks nice and simple and the probe is mounted externally on the coolant pipe so no leaks!

[sprevett]

mod-wise adjustable fan switch took all of 10mins to fit - really good kit with all leads & probe the right length etc., although I added a small mod of my own which was a gunGum metal exhaust repair clamp which clamps the probe perfectly to the metal swan-neck pipe. will post pics soon.

[Barkychoc]

You can also get a thermostat housing from Rimmers that will take a 22x1.5 thread otter switch. I bought one when I had to replace a corroded pipe where my otter was located on the V8S.
Its listed as a thermostat housing for Range Rover with aircon, but its the only one they have in stock anyway!

[Barkychoc]

Found a pic

[sprevett]

what an excellent mod! i assume it fits all wedges?

[Barkychoc]

I assume so, it was a direct replacement for the thermostat housing on my pre serp V8S, I just had to extend the wires to the switch, I just used cableties and tied the cable underneath the top hose.

[jmorgan]

Er, I have to have one. Good find.

Superb.

[JR]

rev-erend said:

Honestly the best idea is to seal it up completely and either get a new top steel pipe and have that converted to contain an otter switch (Richard Thorpe) and ACT will probably be able to have this done.. or use an otter which can be put in the top pipe near the rad..

Yep. This is what the factory did to mine; it also measures the temp where it needs to be measured.

[rev-erend]

Barkychoc said:

Found a pic

That looks like a very neat solution... like that

[Barkychoc]

Bet you can't buy it for 99p

http://cgi.ebay.co.uk/RANGE-ROVER-SD1-LAND-ROVER-P...

Its about £35 + vat I think from Rimmer Brothers excluding the switch.

Edited by Barkychoc on Tuesday 6th April 09:52

[adam quantrill]

Looks neat but I've been thinking about it and both are wrong. The otter in the rad is on the hot side, and this is even worse next to the thermostat.

I think what you really need is a switch in the return pipe from the rad, set at a lower temp of course. Then when the rad is doing its job OK passively, the fan won't come on. If the rad can't flow cool air (moving too slowly or it's a hot day) then hot water will pass through and the return temperature will rise, and that's when you need to switch on the fan.

[Barkychoc]

adam quantrill said:

Looks neat but I've been thinking about it and both are wrong. The otter in the rad is on the hot side, and this is even worse next to the thermostat.

I think what you really need is a switch in the return pipe from the rad, set at a lower temp of course. Then when the rad is doing its job OK passively, the fan won't come on. If the rad can't flow cool air (moving too slowly or it's a hot day) then hot water will pass through and the return temperature will rise, and that's when you need to switch on the fan.

I'm not sure I agree!

If the otter is on the return to the block by the time it triggers you've got an entire radiator full of red hot water, some of which it going to go back into the engine and circulate around an already hot engine, and presumably the cylinder heads are even hotter.

I would have thought the earlier you detect a hot engine condition the better.

[JR]

Barkychoc said:

I would have thought the earlier you detect a hot engine condition the better.

This is what John Ravenscroft told me.

[AM400]

Barkychoc said:

Found a pic

Is it me or is the outlet on the opposite side to the standard housing?

[jmorgan]

Mine is a range rover block so looks OK, checked before ordering. Acid test should be in the post.


(of course that should be seen as OK for mine, not an OK for anyone else until they check)

Edited by jmorgan on Tuesday 6th April 22:08

[rev-erend]

JR said:

Barkychoc said:

I would have thought the earlier you detect a hot engine condition the better.

This is what John Ravenscroft told me.

I would agree .. the sooner you know about it the better.

That is way a 72 degree stat is needed in hot countries .. tis stat opens 10 degrees sooner. OK 72 degrees is not an idea solution for the UK - as in the winter you would have only a warm heater but pop down to Spain in summer and it would be essential.

[Barkychoc]

AM400 said:

Is it me or is the outlet on the opposite side to the standard housing?

New and old pictured below

Just incase you are wondering I have had my car running with this arrangement - and it works well the temp gauge doesn't move a great deal above 90 as the fan is pretty responsive - as soon as there is some extra heat the fan is running.

Edited by Barkychoc on Wednesday 7th April 10:34