I’ve worked on the gas delivery systems in my Vettes and Mustangs. This always involves removing gas lines from the carb or throttle bodies and of course the possibility of leaks after re-installing them. One of the last things you want is gas leaking here and there in your engine bay..NOT GOOD!
I’ve always use teflon tape to wrap the threads.
This helps seal the connection, and sometimes with older cars you need that was the threads aren’t bad enough to replace….errk…Getting new fittings and flaring the gas lines is sometimes necessary and can be a pain..but if threads are really worn, take the time to do that. Yes..I know cutting the lines and get correct type hose and some clamps you’ll be fine…but it won’t look as good and since both of my car are trophy winners at car shows, I try to keep them looking professional.
Using the tape does have a of couple drawbacks. It can form a lip around the gas line opening, partially blocking the flow. Additionally, pieces can tear off during installation and get into the system. So some companies offer a thread sealer in a tube, which is made of Teflon in paste form. I’m using that next time I have to go into the fuel systems. I know that Permatex makes some (what don’t those people make!?!?!!?!). They call it thread sealant and it comes in different “models” like High Performance and High Temperature.
Thanks for reading.
Tim
On my Corvette, the fuel line connections are pipe thread, and this is quite a good idea. On my Mustang, the connections are inverted flare, and teflon sealer is useless on them. Late-66 on often had pipe threads on the carburetor, and other places, and should have the teflon, of course.
David Suesz
True David. My Mustang is modified and has the thread into the carb.