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General Tech How different is NPT thread from BSP thread?

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T

TuffTR250

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Revotec has a radiator screw in temperature sensor that looks very good. However, the thread on theirs is 3/8 BSP whereas the fitting in my radiator is 3/8 NPT. How different are those threads, and is there any chance the 3/8 BSP sensor would go into my 3/8 NPT fitting and not leak? Thanks!
Regards,
Bob
 
I found this:

https://pipeandhose.com/node/2

One big difference is that 3/8" NPT is 18 TPI, 3/8" BSP is 19 NPI.

That said, I put a 1/4" BSP oil pressure sender (male) into a 1/4" NPT (female) adapter, and got it to hold air even without excessive torque. I ended up using JB Weld just to be sure, and I wouldn't do it into a part that I couldn't replace.
 
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