Fuel line ferrule

[dean333]

Btt

 

[Y-Blockhead]

I can’t tighten the line enough to get it to not leak, there’s no more threads left to tighten.

I think those are two separate issues.

Not really. If he is running out of threads to tighten down on the ferrel, The gas line will pull right out. No amount of glue will prevent that.

 

[katy]

At times I've used cotton string for a packing. Wrap 3 or 4 turns around the line, between the nut and the ferrule. YMMV.

 

[JayJay]

Not really. If he is running out of threads to tighten down on the ferrel, The gas line will pull right out. No amount of glue will prevent that.

I agree. What I was trying to say was that a bit of thread sealant will help with assuring leak-free, and I guess I should have qualified that by stating that I was assuming that the ferrule was properly crushing onto the tube. Clearly if you can’t crush the ferrule you will have leaks. And you can’t do that if your nut runs out of threads before crushing the ferrule.

In a former life one of my tasks was to teach young scientists how to properly assemble specialty gas systems using SwageLok fittings, and getting the ferrule properly fitted and assembled on the tubing is critical. One way to mess that up is to have too much tubing extending from the front of the ferrule so that there is insufficient room for the tubing to move once the crush onto the tubing begins. That will manifest itself during reassembly as “running out of threads”. Having too little tubing is another way to mess up the crush as the front of the ferrule won’t have any tubing to bite into. Sort of a Goldilocks thing.

Both of these scenarios assume that there is a proper match between the nut (on the tubing) and what you are installing into - sediment bowl, carburetor, manifold, whatever. An extra thick ferrule is one possible solution.

Sorry for the confusion.