How much coolant will I lose from the temp sender

[Michael M.]

I've had some temp gauge issues and have isolated the problem to the sender. If I remove the temp sender will I lose a lot of coolant? I've done a lot of work on my car but never removed the temp sender with the coolant system full. Thanks. '68 L36 (427/390). I assume of course that I must wait until the engine has cooled.

[Edward J.]

Re: How much coolant will I lose from the temp sender

Mike, if the location of sender is on the top of intake, and you do it quickly, you won't loss much, if its located in the cylinder head then best to drain the radiator down maybe about a gallon. keeping the radiator cap locked in place while replacing sender will also help with coolant loss.

[Michael M.]

Re: How much coolant will I lose from the temp sender

Thanks. It is in the cylinder head, so I guess I'll be draining out some coolant.

[William P.]

Re: How much coolant will I lose from the temp sender

I would do this with the engine cold and I would not drain any coolant . First remove the rad cap and release any pressure , put the cap back on tight, have the new sender ready and close at hand, remove the old sender and quickly put the new one in . You shouldn't loose very much coolant , with the cap on there is no vent for air to get in. That is how we did it back in the day when I worked flat rate .
Bill

[Don L.]

Re: How much coolant will I lose from the temp sender

Michael: Interesting post. I wish I had asked before venturing into this ordeal last year. I rolled the dice instead, trying it Bill's way and made a mess of the cyl head, ignition wiring, etc. Bill's method didn't work at all for me in my '72 350ci.

Ed: where were you last year???

[Michael M.]

Re: How much coolant will I lose from the temp sender

Thanks for the replies. I'll let you all know how it goes. First, I have to order a new sender. Lectric Limited seems to have a proper replacement.

[Edward J.]

Re: How much coolant will I lose from the temp sender

Michael: Interesting post. I wish I had asked before venturing into this ordeal last year. I rolled the dice instead, trying it Bill's way and made a mess of the cyl head, ignition wiring, etc. Bill's method didn't work at all for me in my '72 350ci.

Ed: where were you last year???

I was there and looked for you, I guess you decided to rent out your spot at Carlisle.