Main Fuel Tank Fitting Installation Question

[M Towsley]

Hi all,

I pulled the fitting from the main tank, (about three turns out), as it did not have a screen. The screen was installed and I test installed it today just to see how it would line-up with the firewall hole. I did not have fuel lube or any other product on the threads as I wanted to see how it went. I discovered after cleaning the fitting and the threads it now easily screws in four turns, but is still not completely tight, even though it is pointing toward the firewall opening. I am afraid to tighten it another full turn.

Any suggestions as to what to do. The prior fitting was tight, but probably due to paint and old thread sealer.

Thanks in advance!

[Mark Julicher]

Re: Main Fuel Tank Fitting Installation Question

If it is "nearly tight" you might be able to use Aviation Permatex instead of Fuel Lube and it should hold fuel and work fine. If it is "not really very tight" you may have to chase the threads a TINY bit and torque it firmly.

[astjp2]

Re: Main Fuel Tank Fitting Installation Question

It needs to be tight, dont use sealant if at all possible. Its the taper of the NPT thread that is supposed to seal the fitting. Tim