Leaky fuel sending unit

'93 XJ 4.0L

My fuel sending unit is leaking.

It is definitely not leaking at the tank flange or O-ring.

I've narrowed the leak to come out either at:

1) the hard plastic "plug" where the wires come through the flange disk.

2) ...or the joint where the tubes are brazed onto the flange disk.

I've tried several times to wipe everything dry in order to try to spot the
exact origin of the leak but this has proved very difficult because even the
tiniest amount of leaked fuel seem to instantly seep across and wet the
tubes and plastic plug at the same time.

The locking ring and flange are dry, so it looks as though they're OK.

None of the usual parts sources and self-pick yards seem to have this item.

The local Jeep-Chrysler dealer quoted me $439.00 for a new sending unit.
He didn't mention whether if that included the pump ...but I positively felt
as though it was my wallet that was being "pumped".

I was thinking of maybe using some sort of sealant on both the inside and
outside of the suspected areas of the leak.

Has anybody done this?

Any recommendations for a sealant?

I thought about using J-B Weld, but that stuff can sometimes take over
24 hours to set.

I picked up the whole assembly at a u-pick lot for $8.50. I found them still in place on every XJ I looked at so it might be worth taking a first hand look for yourself. If you want to try JB Weld, they have a quick setting formula which should be ready to go in just a few hours. I'd clean the area with MEK or acetone first.

I had the same problem on my 93. On the backside of that plastic plug is an o-ring. That plug is held on by a snap on retainer from the other side. If it gets loose, the o-ring can't seal and it leaks. I couldn't get mine to tighten and I couldn't find a new retainer that would work. I ended up getting the whole assembly from JC whitney. It doesn't leak but it's noisy as hell. I also had to bend it a little so it would go into the tank. If I could do it all over again and had the money, I would go oem.
Mike Harris