71OldsCut

Hi guys,

So I am going to be changing the carburetor among other things this weekend. I just went out to make sure I have everything I am going to need to do it this weekend and noticed something that lead me to some questions. The flarenut holding the fuel line in - whoever had it apart last messed it up really nice and I can see where they used vise-grips to get it back in. It is in rough shape. Best I can tell it is a 9/16" wrench, does that sound right?

What is in there, just an o-ring? If so, what size? I would like to pick up a new one to put in there. Is some of that thread tape a good idea? Other than that it looks straight forward, I just want to make sure I have everything I need to deal with the flarenut and whatever is behind it. Hopefully they didn't go too crazy with the vise-grips tightening that up or I may never get it out.

Thanks!

joe_padavano

The fuel line fitting uses an inverted flare, just like brake lines. The seal is the metal flare on the tube to the metal cone inside the fitting. There is no o-ring or any other type of seal. Since the threads are not in the seal path, using any sealer on them is a waste of time (other than a tiny amount of anti-seize to prevent problems next time). Be sure to use a wrench to hold the main fitting at the carb when you loosen or tighten the fuel line flare nut. Not doing so is a great way to strip the pot metal threads in the carb body.

71OldsCut

Thanks, good to know. So basically just be as careful as possible, make sure to the fitting at the carb and hope that the flarenut isn't on extremely tight.

joe_padavano

When you try to reconnect the fuel line, one trick is to start the flare nut threads in the carb BEFORE bolting the carb down.

dragline

Using an improper wrench on the lines causes all the trouble. Invest in a set of "flare nut" wrenches designed for this particular job. You'll thank yourself every time you use them. Always use a back up wrench on the filter fitting to prevent damage to the carb threads.

joe_padavano

Excellent advice, however the OP says that the nut has already been chewed up by a vice grip pliers, so the flare nut wrenches are unlikely to work this time.