Should i use a thread sealer on my oil pressure sender.

[Totally 80s]

I am going to be putting in a new oil pressure sender (the one by the oil filter) and was just curious if you guys put any kind of thread sealer on before installing or is it best to just install it dry?

[WelmoedJ]

The one I purchased from Herveys came with a pre-sealed thread (dark red stuff).
Since oil is pressurized you mmay see "sweating" if not sealed.

[Bitsyncmaster]

That's a good question since the threads make the "ground" connection to the engine block. I have found that using a sealer (permatex) has always worked. I would think even a teflon tape would be cut by the threads when you install it.

[David T]

You don't have to use anything but it won't hurt to use teflon tape of threadsealer. It is a tapered pipe thread and a brass fitting so when you tighten it up it will seal and also make a ground connection (as long as you didn't wrap it with 1/2 a roll of teflon tape!). And if it does leak you can always tighten it a little bit more. BTW there is a replacement oil sender that actually makes the oil pressure gauge work correctly as opposed to the stock piece.
David Teitelbaum

[Totally 80s]

I had to pull the brass fitting out to get the old sender out. I am thinking of putting a little thread sealer on that as well. I think I was getting a little leak from it.

[Bitsyncmaster]

I never thought sealer was necessary until I made my own coolant pressure tester from pipe fittings and a pressure gauge. Without sealer I could not hold 15 PSI for more than 5 min. After the sealer it held overnight.

So now, I always use a sealer so you get no weeping oil film.

[David T]

I used to be a big fan of Teflon tape. Much neater than pipe dope. After using it for a long time I realized, on pipe threads, nothing beats pipe dope. Besides, the teflon tape they sell nowadays doesn't seem to work like it used to. The other problem with teflon tape, especially on a closed system, is the possibility of getting shards loose inside and having them plug things up. The bottom line is you really don't need anything, pipe threads are an interference taper fit and if it leaks you just tighten it somemore. Especially with brass fittings. They will deform easier and seal better. About the only place I use teflon tape anymore is on plastic drain fitttings like sinks and cleanout covers. Plumbers are a very conservative bunch. I see them use pipe dope and yard and then crank on the fitting like it will never come apart. They hate having to go back and retighten things because of a leak.
David Teitelbaum