How to remove fuel fitting on nylon gas lines

[sunalp]

I know, sounds like a silly question and usually I can get around this issue, but this car I'm
working on is special. It's a one owner car purchased new in London ( as an export model)
in 1968 and has remained with the family since. It has 38K original miles.

I cleaned and sealed the gas tanks and the crossover tubes . Used new rubber and clamps.
The owner was having the common stalling issues with paint flakes clogging the jets.
The car has its original nylon gas lines with the original nuts. They take a 7/16 wrench but
don't seem to loosen. If I keep turning it starts to twist the lines so I'm asking if anyone has
successfully removed them and retained the nylon lines? This car is very special and original
and I'd like it to stay that way. I only want to remove them to blow any remaining paint out
of the lines. Don't want to unnecessarily break them.

Any ideas are truly welcome!
Cheers!
Steve

 

[DanR]

Steve, Just left you a message to your phone.

If you are speaking about the line connection at the crossover tube, I sometimes have had to put pressure on the plastic line by pulling a bit to relieve tension on the nut as you loosen it.

The "flap" that protects the fuel line doesn't allow much flexibility to connect or disconnect the line. I have also "opened" slightly the flap a bit allowing me to work the nut..........

 

[volvoguys]

Assuming you are trying to remove the fitting/olive at the center tube, I'll build on what Dan has offered: I've broken a lot of these cars and find the fuel line so difficult to remove I usually cut it off. I suspect that over 50+ years the nylon has somewhat vulcanized and is more likely to crack or break that flex off the inlet tube.

You might consider using a heat gun to soften the line enough it'll come off. I suspect that might distort it so upon reattaching you might need to again soften the line and massage it for a tight fit once its on.

 

[sunalp]

Thanks Dan & Mark,
The center connection on the crossover tube is just a normal compression fitting, no problem with that.
The same goes for the line in on the fuel pump. It's the fitting on the line out from the pump where I'm
having the issue. It's not a normal compression fitting. It's a brass nut that has the nylon line inserted
and by tightening the nut it somehow seals the line. There's no olive in there. Never seen these before
and already destroyed the one to the carbs. I fixed that one by inserting the nylon line into rubber gas line
and clamped both ends. Perhaps that's the only way to get these off?
I'll take a picture of this and post in a short while so maybe a visual will help.
Thanks again guys, really appreciate it....Dan I'll give you a call later this morning.

Cheers!
Steve

 

[sunalp]

Here are a couple pics of the offending fastener.
Cheers!
Steve

 

[DanR]

I would use the new plastic gas line and replace it all trying to keep the nut(fitting).

I have replaced the old with new black plastic lines on my Alpines.

Bet you can too!

 

[sunalp]

Thanks Dan,
I'll try and find some line tomorrow. I do think it's the way to go.
Cheers!
Steve

 

[hartmandm]

Here are photos that I believe are the original parts at the carb end. From what I can tell, the threads in the nut bite onto and then compress the fuel line onto the metal pipe. The fuel pump end could be the same setup, but I have never loosened that end.

Mike

 

[sunalp]

Thanks Mike,
That's the end I destroyed as it just twists the nylon and doesn't really loosen. I wonder if I can get
the old nylon out of the "nut" if it'll work with the new nylon? Something else to try today!

Thanks to Dan R and his suggestion for new nylon lines. I was able to buy it ( 5/16ths ) at a local
NAPA and it works really well. Not cheap though, 25 ft cost $50.

I'll post back and let you know if the "nuts" can be reused.
Cheers!
Steve

 

[sunalp]

Well, I have attached the nylon furl line from the fuel out on the pump to the T on the carbs with
the "nuts" removed from the original line. So far, they are tight and won't pull off. I'm off to
put some gas in the tanks and see if anything leaks. I'll post pictures later on.
Thanks again for everyones help!
Cheers!
Steve

 

[sunalp]

OK, car running with nice new cleaned and sealed tanks, all new gas line . The line running from the pump out to the carbs
is using the "stock" nuts that I removed from the old line. They're on there and there are no leaks.

Going for a long test drive this afternoon if the weather holds and we'll see if there are any leaks.
I don't think there will be as everything is tight and the tanks are firmly installed.

Here are a couple of shots of the lines with the nuts installed.

Cheers!
Steve

 

[hartmandm]

Steve,

Was the same type of nut that is at the fuel tee (carb end) also used at the fuel pump end?

Thanks,
Mike