Oil sending unit.

[Ziegelsteinfaust]

I have been chasing oil leaks till I found it coming from the oil sending unit. When rpm and oil pressure build. Oil squirts past the threads.

So when I found it. I compared it to a pipe plug, amd noticed it lacks the tapper needed to seat or seal correctly.

So am I missing something? Like I need some adapter?

[Willshook]

GEN I SBC oil pressure sending units use a tapered thread, but it's 1/8" NPTF and not NPT. It's a finer thread and taper to allow it to seal without sealant because the sending unit needs to ground through that connection.

If the threads are clean and it's tight - it shouldn't leak. I would tighten it up and expect that will fix the issue.

[RustyPile]

Deleted: duplicate posts....

[RustyPile]

Originally Posted by Willshook

GEN I SBC oil pressure sending units use a tapered thread, but it's 1/8" NPTF and not NPT. It's a finer thread and taper to allow it to seal without sealant because the sending unit needs to ground through that connection.

If the threads are clean and it's tight - it shouldn't leak. I would tighten it up and expect that will fix the issue.

Willshook, most of the time your information is spot on, but your description of NPTF is incorrect.. As we all know, NPT stands for NationaL Pipe Thread.. NPTF stand for National Pipe Tread Fuel.. The thread is the same pitch but the threads are of a slightly different shape.. the "valley" isn't as deep and the "peaks" are more pronounced.. This contour provides a better seal that does not need any sealant..

https://www.buyfittingsonline.com/pa...ifference.html