Fuel line compression fitting leak and fuel rail schrader valve

lennonjon

Well-known member
Jun 21, 2010
65
4
Ashtabula, OH
Hi all,

1996 Disco SE7 with the non-Evap fuel system.

Today I installed a new fuel pump in order to get my garaged Disco back on the road. Two issues came up, that I was hoping someone might be able to help me with.

First, I found that whoever installed the previous fuel pump stripped the first 1/4-inch of the male side (fuel line side) of one of the compression fitting that attaches to the fuel pump. As such, I was not able to thread the new nut onto it. As an attempted fix, I cut off the 1/4-inch of stripped threads, filed everything down to be smooth and attempted to connect the compression fitting. It seemed ok at first, but after running the truck for a while a very minor leak appeared. I'm pretty clueless about compression fittings on fuel lines, so was wondering if it is possible to cut off the old male side from the fuel line and install a new one. If so, does anyone know what size fitting it is (as well as the ID of the fuel line)? Or does anyone have other suggestion that doesn't involve me having to run a new fuel line?

Second, I noticed that the schrader valve on the fuel rail is leaking. I didn't have a valve tool with me at the time to see if the core could be tightened down to fix the leak. Assuming I need a new valve core, does anyone know a source for one with o-rings that are compatible with gasoline? I found in another thread that you can just use one from a bike tire, but that they leak after a while and would rather get the correct valve, if possible.

Thanks for any help!

Salud,
Jon
 
Last edited:

DiscoClay

Well-known member
Mar 18, 2021
444
89
Chapel Hill, North Carolina, USA
Hi Jon,

Did you ever find out the actual size spec for the hard (metal) fuel line or any other connector details?

I have a 1995 manual trans NAS Disco (USA/CA spec) with the pre-"Advanced evaporative" system.

I can confirm the compression fitting is a "12mm x 1.0" concave (using an "olive" or ferrule to mate the concave mating surface of both the female end (on the pump) and the male end (on the flexible rubber hose),

QUESTION:
Does anyone know the *actual size and type specifications* for both the fittings and the hard metal lines?

It appears the lines are 8mm (0.3149 inches) but when I measured my own hard lines with a caliper the number was closer to an actual 5/16" line (0.3125 inches). I know this number is close but ..well, compression fittings are pretty precise.

Does anyone actually know? None of the parts suppliers indicate any details other than the rover part number.

Also, about that compression fitting: is that some common metric compression nut fitting? I have seen lots of 12mm x 1.5 compression fittings but few in the 1.0mm thread pitch.

I am attempting to replace the rubber hose ends and convert everything to 6AN and I need to cut off the old crimped-on rubber ends (at the fuel filter and the engine). I am attempting to use the original metal lines (unlike the rest of the wagon, they aren't rusty :)