Rad thermo switch removal tool?

[hardwick53]

I need to replace the rad mounted thermo switch for the fan. Anyone know what tool or socket to use?

The new thermo switch measures 29mm, so is a deep socket needed or ?

Cheers Pat

[kevtherev]

Adjustable wrench will do

[hardwick53]

30mm 1/2" drive deep socket from halords, £7 ish, just the job.

[Ian Hulley]

30mm 1/2" drive deep socket from halords, £7 ish, just the job.

So why ask the question if you already know the answer .....

[itchyfeet]

Move along nothing to see here

[AdrianC]

Adjustable wrench will do

^ this. It goes into plastic, so doesn't need or want to be too tight.

[California Dreamin]

Was going to say.....the switch screws into plastic 'brass insert' and comes undone very easily with vice grips/adjustable wrench (Bahco type)/water pump pliers (sliding jaw type)....2 second swap over (with new washer) don't over-tighten....quick bleed from 13mm bolt left top of rad....done.

Martin

[sternal]

And if you do it when the engine is stone cold you won't need to bleed, that was the advice given to me from one of you helpful guys.
Did mine today

[AdrianC]

And if you do it when the engine is stone cold you won't need to bleed, that was the advice given to me from one of you helpful guys.
Did mine today

If you do it with the engine stone cold, the 'stat will be closed and there won't be any pressure in the system. But you are still removing a bung with a reasonable column of water above it. I'd still bleed the rad. For the sake of the effort involved in getting the van warm, and cracking open the bleed bolt whilst the engine's held at revs, it seems a false economy not to.

[hardwick53]

I asked as I had never changed one before. I assumed it would be very tight and visibly access is restricted. I got a socket the next morning before I got a reply which I thought would work.

Thanks for the posts I know more about it now. It's a learning curve when you commit yourself to renewing parts in the cooling system following the MOCAL oil cooler overheating & bursting. So its great to have a community to lean on. Thank you all.

[sternal]

Re: How to fit a radiator switch

Postby Mocki » 13 Oct 2013, 12:26
If the system is hot, as I said earlier, means the thermostat will be open, meaning the whole water system is connected and flowing, so apart from not burning yourself, by doing it stone cold the thermostat will isolate the rad circuit, meaning the only place the air can go is the rad circuit, and also means that the will be a vacuum in the system, meaning less coolant will come out of the switch oriface because no air can get in other than through the hole the coolant is coming out of.

You won't need to top up any unless you take ages and let lots out.
If it's one out one in you will loose less than a cup full, the top up tank ( behind the number plate flap ) will compensate that small amount and you shouldn't need to fill the header tank ( in the engine bay only accessible with the hatch off)

Don't undo the bleed screw on the rad!

Re: How to fit a radiator switch

Postby DuaneEddy » 12 Oct 2013, 20:13
Guy's
I've used these meters in the pictures and you get different readings whether it is matt black or shiny

Question
Is the switch 3 pin or 2 pin?

Resolution
Order new - fit when engine cold - test
As Ian (and boy's) have said if engine cold - no burny - you should not need to bleed if you are quick replacing switch - water loss is minimal

I ran the van up to heat and tested the RAD TEMP using the thermal thermometer (took about 30 mins and a quick drive ) fan cut in and RAD had even temp all over so i guess this time I didnt need to bleed...or do I still need to bleed ? As this is how it should be ?