I will be putting a new low temp fan switch in the camaro later this month.

My question is, how much coolant will leak out when I remove the old fan switch?

Also, should I use some RTV when putting in the new one?

Thanks.

A good bit of coolant will pour out, but it'll make a huge mess. This is from personal experience, when I replaced mine, I just removed the fan switch and let the coolant splash/drain out, but I would highly recommend just removing the engine coolant drain plug instead. It will drain out more coolant that way, but it won't make a huge mess on the garage floor.


I've always been told not to put any kind of thread sealant on any kind of coolant temp. device. Most of them ground to the block or cylinder head itself, and if too much sealant is used, no ground. Just for comparison, I didn't use anything on the threads of my fan switch, and it has been leak-free.

I've heard the exact same thing about not using any sealant, but when I replaced mine with a JET low-temp one, I don't remember any such warning. I vaguely recall asking someone at JET about the fact that with one wire going into it, that it had to ground to the block and thus one really couldn't use sealant. He told me that the tapered thread at the top of the switch would "cut through" the sealant and contact the block threads allowing it to ground. I used some sealant, and the switch worked fine. Also of note, the factory gauge sending unit on the other head has one wire going into it as well, and when I took it out, it had sealant on it, too, and it has worked since the car was new. I'm not trying to be contrary or confuse you, but you should know all the facts before you make your choice. Good luck.

It makes perfect sense to me. I've always wondered about that, if it is really true or not, especially with the CTS considering it has it's own ground wire.