I found a small leak where the fuel pressure gauge sending unit screws into the FPR. I wrapped the threads with teflon tape, but maybe I didn't use enough. Can someone please tell me the correct procedure for wrapping fittings with teflon tape? How much is too much? TIA.

BTW, I have an Areomotive FPR and a Defi D-gauge fuel pressure gauge which requires an adapter to screw into the FPR.

 

I use teflon paste and have better results with no risk of getting tape on the inside of the fittings.

 

I usually hold the fitting in my right hand with the threads facing left and wrap away from me (If that makes sense). I usually go around two times or so and have never had any problems. You could also consider using the yellow teflon tape, which is used for oil and I believe natural gas?

-Dan

 

I've tried the paste before and it leaked like a dripping faucet.

 

Where can you buy the yellow teflon tape?

 

Home Depot and Lowes sell it.

I always use a liquid thread sealant, you can probably pick up some high temp stuff made by permatex at the local auto parts store.

 

Teflon tape is really only meant to fill the minute voids left in between tapered threads and technically it may not be needed at all. If you have a chronic leak at a tapered thread and have a layer or two (no more than 2 for that small of a thread) of tape in there I would guess that:
- one part might be out of round
- you're not tightening it enough
- you may have a mismatch of threads. There are several styles of thread right around the 1/8" NPT size but won't work together. Without the tape do they feel like they fit well?
- because the threads are cut on a taper, someone may have run the tap too far into the FPR or the die too far on to the adapter and the thing bottoms out before the threads lock together.

 

i've used the liquid teflon before on a fuel pressure gauge and didnt have problems.

 

Well, I'm not certain if I'm tightening it enough. Sometimes I can be a bit heavy-handed and overtighten things. Better to be a bit loose than too tight and break. The sending unit has an adapter to match the FPR threads, so I doubt they are mismatched. I hope it's not one of the other causes as I wouldn't know how to be certain if it was.

 

When you tighten it and it doesn't feel like it's getting any tighter but still spins you might have went too far

 

Oh man I hate that feeling. Time to pay for a helicoil kit! lol

 

Something i do automaticly is put the teflon paste on and tighten it then loosen it and retighten it the anodize coating sticks and makes it feel tight when its not!

 

Its called "PTFE Thread Seal Tape" MIL Spec T-27730A. Its also used for gasoline, propane, and natural gas.

You can get it at places that sell prophane.

Wrap it around twice