L body fuel system upgrade

**Skibbe** · 10-10-2009, 04:16 PM

Well, walked into the garage this morning and smelled gas... Few drips coming from the wiring as it exits the bulkhead. Uh-Oh!

Dropped the tank just now, pulled it all apart again... and it was the wire itself allowing gas to escape! The gas and oil friendly wire I picked up has this extra clear sheath on the outside, and gas got into that sheath on the fuel pump side and leaked right out like it was a straw.

So, I tried to solder to the existing wiring connector in the bulkhead, but being riveted to the bulkhead, it took too much heat and loosened the plastic. I'm sure that's going to leak now too. So, I need to find another bulkhead and fuel pump assembly and try again, using the smaller wire that's on the hanger.

Should have gone with an external pump probably...

**Skibbe** · 10-16-2009, 09:14 AM

Ok, here was the culprit, I know gas was getting out through the wire between the clear outer sheath and the insulation... it was wet with gas for the length of the wire in there... Also possible is that gas was getting in the copper stranded wire itself:

**Skibbe** · 10-16-2009, 09:17 AM

So, here's the second attempt. Rather than route the wire through the old feed tube, I drilled new holes, a separate one for each wire. JB Weld was used, then later stregthened with some gas tank repair epoxy to make sure any jolt to the wire didn't crack the JB weld. I also went to solid core wire, and stripped the clear sheath off of it, for the portion through the bulkhead.

If this leaks, I'm ordering a fuel cell.

**BadAssPerformance** · 10-16-2009, 09:40 AM

Is JB weld conductive?

**Skibbe** · 10-16-2009, 09:53 AM

I was worried it was, that's why it's only touching the ground wire and not the power wire.

**BadAssPerformance** · 10-16-2009, 09:58 AM

Gotcha... didnt see that!

**Skibbe** · 10-16-2009, 10:02 AM

I thought about it after smearing some JB weld on the back of that factory plug, hence clipping off the power terminal there too! Doh!

**BadAssPerformance** · 10-16-2009, 10:07 AM

Doh!

Another thought... doesnt McMaster Car sell sealing bulkhead wiring connectors?

**Skibbe** · 10-16-2009, 10:17 AM

Link?

**BadAssPerformance** · 10-16-2009, 10:24 AM

Cant find them, my bad

**Skibbe** · 10-16-2009, 10:35 AM

I've been searching everywhere for something like that, closest I've found is from FuelSafe for fuel cell applications and the intank wiring harness with bulkhead is ~$50!

May just have to work with a new pump hanger and bulkhead, going back to the original wiring plug.

**BadAssPerformance** · 10-16-2009, 10:36 AM

Ouch!

Yeah, a new hanger might be best

**Skibbe** · 10-16-2009, 10:40 AM

Someone must make SOMETHING though. How many cars are out there with intank pumps??

**iTurbo** · 10-16-2009, 07:21 PM

The later turbo mopars ('91+) had a sending unit with a removable bulkhead electrical connector. Made it a lot easier to braze in the new tube when I did mine.

Here it is with it removed:

Not sure if it's possible to install a newer hangar (w/reservoir) into an early tank though. This is the internal pump I did for my Spirit R/T (pic on page 2). Hope this helps.

**Skibbe** · 08-14-2013, 10:48 PM

Little update... Last year when I parked the car for the season I was getting some fuel leakage out of the bulkhead again. Thought it was the wiring again at the time. FINALLY had a chance to pull out the pump assembly this year and take a look. JB Weld apparently isn't fuel safe as the JB Weld on the inside softened up and was falling off.

I ordered a new fuel pump hanger from Rock Auto. Unfortunately the one I received only had a two wire plug (no fuel level sensor wire?). But I found and ordered one of these from Racetronix: http://www.racetronix.biz/itemdesc.a...A%2D4W&eq=&Tp=

Hopefully more progress soon...

**itoktoeatfish** · 03-19-2014, 12:26 PM

Alittle old I know, but thanks for keeping this thread updated!

**wallace** · 03-20-2014, 07:41 AM

I drill out the rivets on the factory wires and reuse the two plastic pieces. Replace the rivets with #6 machine screws. Ring tongue connectors on inside and outside. Glue it together with fuel safe silicone. Takes a bit of time but it doesn't cost $50.

**Skibbe** · 05-03-2014, 11:54 PM

That's a good idea Wallace, wish I had seen your post sooner.

I decided the Racetronix fitting was too big... I then tried to braze the extra wiring holes in the bulkhead (so I could just run the wires out the top of the tank through the spillover valve grommet) and that went south and pretty much ruined the bulkhead and hanger assembly... which lead to purchasing a brand new fuel pump hanger...

So, this time around I'm just adding one hole for the -8 AN bulkhead fitting for fuel supply and going back to the stock wiring plug. I'm also now feeding the fuel return just back into the old feed tube, we'll see if it is large enough. This is a Walbro pump which required modifications to the plastic pump housing. I carved the housing to fit around the Walbro and then secured it with two screws with washers... this is because the Walbro pump is longer than the stock replacement included with the Airtex pump assembly.

Here's the photos: