B21FT oil pressure sensor leak

1982 244 Turbo.

I am leaking oil where the oil pressure sensor screws into the red block, in front of the oil filter.

As my car has a gauge and not just an idiot light, a sort of weird set up is used: a brass adapter threads into the block, and the pressure sensor threads into the adapter.

The adapter is cocked at thirty degrees, presumably for clearance (tight space in there).

The problem is that when installed the sensor has a limited area it can fit in, say between ten and fifteen degrees from TDC, but the adapter, when tightened, goes well past this point before it can go not further, maybe another ninety degrees or so.

I tried installing it using RTV gooped over it but that failed, so now I am determined to do it right, whatever and however that is.

Any suggestions?

I don't want to JB Weld the adapter, but that may be the last resort.

I have Loctite 567 which I was going to use for threadsealing, but fear the slop will be too much for it to keep from leaking.

I still use the Teflon tape on treads. That works for me!

Teflon tape is a no no when the sender needs a ground signal through the threads. Use a liquid Teflon sealant instead.

If the threads on the adapter are worn, you may need to replace it. See this post for part numbers.

http://forums.turbobricks.com/showpost.php?p=5366296&postcount=11

I like to use Loctite 592 a high temp thread sealant. But make sure the hardware is in good shape as suggested above.

I did buy a new adapter from a hardware store, but it also spins past the safe stopping point when I tighten it up.

hiperfauto said:

Teflon tape is a no no when the sender needs a ground signal through the threads. Use a liquid Teflon sealant instead.

If the threads on the adapter are worn, you may need to replace it. See this post for part numbers.

http://forums.turbobricks.com/showpost.php?p=5366296&postcount=11

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Thanks. Had no clue and sure I used the tape on two cars for sure. Everything worked correctly so figured I was good. Going to look in to the high temp stuff, just makes sense in that area.

Thanks for the tips.

I am going to try to install it with only the Loctite 592 without tape.

Took awhile to find a vendor that sells it locally, but finally found one.

Crossing those fingers ...

That stuff has always worked well for me. There used to be a version like 562 or something but I can't find that anymore. When we had a B20F in a 75 245 we used it to seal the headbolts before we figured out the head was cracked.

The 592 is better since it's a high temp version. I also use it on fuel filter and fuel pump fittings. Especially helpful on a turbo 240 when a little wear happens on the fuel filter inlet pipe fitting. After a few filter changes the flare fitting part of the pipe can use this stuff to help seal it.

It's messy but good.

The instructions talk about a seventy-two hour cure time, which I take to mean "for ideal results, don't operate the engine for three days."

Presumably firing it up sooner could be inviting the repair to leak.

photoman327 said:

I still use the Teflon tape on treads. That works for me!

Click to expand...

Teflon tape belongs under the sink..The tightening action always cuts thru some of the tape and those pieces of tape enfd up where you don't want it, like inside the erl pump or in the main oil gallery or turbo feed..Someplace but never where you want..

Permatex Ultra-Grey


The meaning of life and the secret of happiness right there.

read the instructions.

photoman327 said:

Thanks. Had no clue and sure I used the tape on two cars for sure. Everything worked correctly so figured I was good. .

Click to expand...

That's cause yoour X-ray eyes are NOT working so good anymore, you need to get some X-ray vision Glasses to see inside the motor..

Luckily they're cheap