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Oil temp probe 1/8 npt installation

tectweaker

Well Known Member
About to install a oil temp probe in the front right port. My question is should I be using any type of sealant or any other compounds on the threads at all?
 
Tapered pipe threads are intrinsically NOT leak proof. The threads allow the fluid to follow the thread unless some kind of sealant is used for assembly.

the Brits came up with BSP threads (British Straight Pipe), which incorporates a positive seal. But you've got what you've got!
 
My Dynon oil temp sender requires a crush washer, and is not NPT, on my IO-360 w/90-degree oil filter adapter.
I ended up using a Dynon specified "option for sealing the sensor to the engine case is Earl's Stat-O-Seal Sealing Washer # 178010 installed between the sensor and the engine case." The crush washer on the Dynon sensor wobbled about a bit.
 
About to install a oil temp probe in the front right port. My question is should I be using any type of sealant or any other compounds on the threads at all?

And is 1/8" pipe thread for a temp probe?? What motor is this?
 
Tapered pipe threads are intrinsically NOT leak proof. The threads allow the fluid to follow the thread unless some kind of sealant is used for assembly.

the Brits came up with BSP threads (British Straight Pipe), which incorporates a positive seal. But you've got what you've got!

Let's expand on this a little.
No such thing as BSP but I know its semantics. You are describing BSPP (British Standard Pipe Parallel) which when supplied with o-ring or gasket is just like any US ORB (o-ring boss) except with whitworth 55 deg threads vs 60 degree US. Our fuel pump fittings are ORBs.

There is also BSPT (British Standard Pipe Taper). Same concept as US NPT tapered male and female ports but again 55 deg vs 60 degree plus the thread pitches and diameters are not the same as NPT.

HERE'S WHY I REALLY DON'T LIKE BRITISH PIPE.

The majority of European and Oriental equipment I have dealt with uses BSPP females with BSPT males crammed into them by design. THEY LEAK because there is only one thread circumference that actually seals vs a continuous matching taper of either US or BS taper system. Especially on steam and hydraulics.
I have asked the OEM engineers about this and they have said it is becoming the standard.

Unbelievable. Whitworth was pretty smart but misuse of his stuff is not.
 
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