School Me on Fuel Line Repair
 

Can anybody school me on repairing nylon fuel lines? I'm having trouble fixing a fuel leak. I'm working on a 99 NB Mazda Miata and some way or another, while replacing the fuel filter, I managed to mangle the sealing o-ring that sits inside the GM Style (5/16ths) quick disconnect fitting that connects the main line from the tank to the (IN) portion of the fuel filter.

Today I slid under the car and cut the bad quick disconnect fitting from the nylon line. Now I'm having a bear of a time trying to fit a new quick disconnect fitting, or a fuel line union in the existing fuel line. Unfortunately there's very little room under the car to really get a good grip on the length of line I have available to me. The vast majority of the videos I've seen online of nylon fuel line repairs are shot from the workbench and pressing the fittings in using fuel line presses, or a combo of tools.

With the room I have available to me, and using a combination of silicone spray and small amounts of heat from a micro torch I was unable to press anything into the line. To apply pressure to the fitting I was using a 1/2in socket extension and a deep well socket that sits inside the inner diameter of the quick connect fitting / fuel union.

Ultimately I can't get a good grip on the line to apply enough force to press the fitting in. As dumb as it sounds, I'm going to try soaking the line in boiling water and applying motor oil to the fitting I'm trying to press in. I've read a few cases of people having luck with that combination.

I've already put a set of hose grip pliers on order along with some Dorman 800-191 unions as a backup solution. If worst comes to worst, I fear I'll have to drop the tank and replace the fuel lines.

Attachment 227545

I yanked all my NB2 fuel lines out while everything was still in the car and replace it all to get rid of the returnless stuff. No need to drop the tank.

Also, pretty sure you can replace the o-rings in those connectors. Not much help if you cut it off, but I'm pretty sure I've seen them available.

The cheapest option would be to replace the line that is damaged with one from a wrecker/breaker.

All the fittings exist to make your own AN lines to replace the stock lines.

A replacement line can be fed down without dropping the tank.