Fuel tank replacement

[WoodenBirdOfPrey]

Tank is out, w00t!  Used a heat gun to heat it up first, and slowly worked it both directions until the grit worked loose and it started to turn freely.  Surprisingly, once I got about half an inch it was loose enough I turned them out by hand.  I don't know that the heat gun was necessarily safe, but it had to be safer than an open flame and it saved the hanger bolts.

I found the leak too.  There's a small hole under the rubber bumper at the circular indentation of the tank.

I'll be heading to Advance tomorrow morning to get some new fuel lines and finish the job up.  I tested my sending unit and it seems to be working good, so I guess that means my issue is a bad ground, probably behind the instrument cluster.  Joy.

[WoodenBirdOfPrey]

I see that my new tank does not have any rubber pads on top of it like the original tank does.  Would it be advisable to put something on the new tank before installation?  It makes me wonder if it's a good idea, since my leak was under one of them.

[mudkicker715]

Good for you.
A cushion is advisible to keep from metal on metal contact.

[WoodenBirdOfPrey]

Everything's back in, full tank, and no leaks.  I re-used the rubber bumpers that were on the original tank, as well as the filler grommet, straps, and hanger bolts.  The plastic part of the fuel pickup was cracked, so I ended up busting that off the rest of the way and replacing it with a piece of 5/16 fuel line.

I can't believe these old fuel lines weren't leaking, they were cracked up pretty bad.


Here's the new routing of the fuel lines.


And I installed an inline filter just before the fuel pump.  Because of the length of the filter I got I couldn't come up with a place to mount it near the tank that I was comfortable about the lines not kinking up.  Seems to be working good so far.


Has anybody ever actually got 25 gallons into one of these tanks?  Supposedly they're 25 gallons from what I've read, but I couldn't have put more than 2 gallons in it out of my can, and it took another 18 at the pumps before it clicked off.

[HappyPappy]

Try soaking them with brake fluid, that may cut through the crud

[BenM]

I believe the small cars are rated at 21 gallons and the big cars at 22. I suspect that this is total volume and includes necessary air space and the small amount in the bottom your pickup needs to operate. If you've gotten 20 in there you're in practical terms full.

You may be able to do better if you had an extra vent or two, especially one on the filler neck. The short behind-the-plate filler can make it hard to get the tank completely full.

[WoodenBirdOfPrey]

You're right, it is listed as 22 gallons.  That makes more sense, sounds like i'm on target then accounting for air space in the tank.

[carnuck]

Just a note, but I'm going to be putting XJ fuel tanks in my '82 Spirit and '82 Eagle wagon (with a relocated filler hole and Eagle/Spirit filler necks) I test fit the XJ tank in the Spirit and it's larger volume will be fine because the car no longer drags it's butt everywhere it goes!
    The 21 and 17 gallon XJ tanks are the same, but the filler neck on the "smaller" one doesn't have vent holes in it.

[WoodenBirdOfPrey]

Why would they intentionally decrease tank capacity by leaving the vent holes on the filler tube out?  Is that like a california emissions thing?  I know on my motorcycle the california model was the same way, the filler dip was lower and cut the 2.4 gallon tank to 2 gallons.  I'm pretty sure that was for the vapor recovery to the charcoal canister or something like that.

[carnuck]

Yep. Only in Califaultia. Motors under a certain size couldn't have the bigger tank

[BenM]

I don't know about California laws, but the XJ tank was a cost-savings thing by Chrysler. They found it was cheaper to make one tank and charge you for an "upgrade" that was just a different filler neck and sending unit then to have two separate tanks in stock. There are all kinds of discussions about it on Jeep forums.

As for the Eagles, you have to remember in 1980 there were no vapor-recovery devices at gas stations, so they just weren't as sensitive to the venting in the tank as the new equipment is. I have just as much problem with filling older cars too.

[Whuntmore]

Threaded rod can be bent for the bolts that hang the gas tank.

I've done this once. It works but its crude. Jeep Cherokees also use the exact same bolt and I've always been in disbelief that I can't find a vendor who carries them. I've spent alot of time looking for one that does. Anyone else find new replacement bolts with the funky bent head on them?

I'm in that position right now.  

A 1993 jeep cherokee's hangers are the same type hanger, but a bit shorter, and the grand cherokee are the same type hanger, but are a bit longer then the regular Cherokee.  They could end up being the same length as the Eagle's are.  I'm gonna check to see how close the GC are.  But in a fix the cherokee will work.  Nuts are 3/8

Update:

Here's a pic of both the eagle's hanger (old one) and the shorter Cherokee (new hanger).  The parts person at Renfrew Chrysler said the Grand Cherokee hangers are a bit longer, so I'm guessing they would be closer to the proper length, but these will work.