swapping fuel tanks

Joined
Jun 11, 2004
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high desert, ca
Now I have a early pig that that had a long range tank in it. It was removed due to it being too big and smashing on rocks from time to time(and also the PO had it sandwiched in place with 2x4"'s). In my search for a good replacement tank, all I could find in good shape was off of a 1979. So I slapped it in and have been using it, but I have a hard time filling it up all of the way. Most gas pumps will shut off when the tank is around half full, like it is not venting enough when filling it up.

My old tank only had two vent tubes, while the 1979 has 4 vent tubes to accomadate emission and evaporative junkola. I ended up just capping two of the vents and using the other two, venting at the upper portion of the filler neck. Does it matter which vent tubes I use? It's a little tough to see inside of the tank. Is there an inherent design that would require a greater amount of venting?

Also, does anyone have a decent picture of how the tank should mount up? I've never had the chance to see a stock fuel tank set up. I mounted mine very securely and with a good ground, but I'm pretty sure it is not the stock configuration for mounting. If someone in so cal needs a long range tank (49 gallons), $100 takes it, as I don't think I'll ever use it again. Has interior baffles, no rust, is not a man-a-fre, but has no mounting tabs or brackets.
 
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Apr 29, 2005
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VA
I have a 72 and a 74 with stock tanks if pics of them will help I will get them online hopefully tomorrow.

Chuck
 
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Sep 2, 2004
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N KY
I also have a large tank in my 55, it is "custom" and not baffled.. I just bought one of the Man-I'm-Afraid tanks used for a good price and plan to bend sliding tubes across the underside to prevent rock damage, etc. This is an option IMO versus the stock tank, shielding the long range tank.
 

mookie

 
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Oct 18, 2004
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West Georgia
hey, i had the same problem with my '71 fj55, i scrapped the rotten, leaky, smelly evaporative system and plugged half of the vent tubes and used pvc valves on the other two, afterwards it would only hold half the usual amount of gas....since then i've put inline anti-rollover vent valves (from a racing application) on all 4 vent tubes and routed the hoses to a breather box (from a vw application) it works great now though lol
 
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Jun 6, 2004
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Hampton, VA
I couldnt find a stock tank anywhere near me so I put a fuel cell into the bed area. 16 Gallons Polyethylene or something like that has the anit aeration foam in it. Its worked well so far but havent used it much.
 

Ming89FJ62

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Joined
Jul 31, 2002
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Palatine, IL
When I was looking for a new tank last year the only place I found one was James at cruiserparts.net. Checked the ususal places, SOR, MAF even called TLC4x4. Ended up having the seam repaired locally; so far, so good. I did replace all the evap lines from the tank to the collector while I had everything apart.
 
Joined
Jun 11, 2004
Messages
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high desert, ca
mookie said:
hey, i had the same problem with my '71 fj55, i scrapped the rotten, leaky, smelly evaporative system and plugged half of the vent tubes and used pvc valves on the other two, afterwards it would only hold half the usual amount of gas....since then i've put inline anti-rollover vent valves (from a racing application) on all 4 vent tubes and routed the hoses to a breather box (from a vw application) it works great now though lol
Ok mookie, are these anti-rollover vent valves something I could find If I searched through a summit racing catalog? Was the breather box stock, or an aftermarket application for a vw? Right now I have to be selective of where I fill up. Circle K will only fill my tank half way, but 7-11 gas pumps fill it up almost all of the way (85%). Depends on the fuel pumps at the gas stations on how much I can fill my tank.
 
Joined
Jun 11, 2004
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high desert, ca
Revisiting an old post.

So mookie, where did you route your breather box? If inside the cab, are you running into fume problems. Also, with the check valves from racer parts, will they still vent at angles, or do they only shut closed when upside down? I ordered the valves after some venting issues yesterday. Vapor locked on a very off camber section with gas shooting out of the filler tube makes me think I need to do something about the venting problem.
 
Joined
Nov 2, 2004
Messages
89
Thought I'd chime in here as I'm trying to fit a larger tank in my 55 right now:

https://forum.ih8mud.com/showthread.php?t=101954

To fill the tank to the top, I believe you simply need to have a line running from a barb at the top of the tank to the highest point on the inlet (above the vent on the tank). This way air and vapors go to the inlet as gas runs into the tank. Since this vent runs into the inlet any condensing fuel droplets or raw fuel that might travel up through the vent go right back down the fill neck into the tank.

My 78 has a barb on the inlet and on the tank for this. My new tank has the fill inlet on the bottom and all vents are in the sender/pickup, so I may relocate it and add some barbs.

There are some pics on mud that show how to add these vents.

-Tyler
 
Joined
Jun 11, 2004
Messages
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high desert, ca
Wow, that's an old post. The reason I got rid of my old tank was because it was too big (held 53 gallons). It was flush with the frame rails and kept gettig banged around. Also, it had very poor mounting in place and poorly designed baffles that resulted in fuel starvation.

The vent problem is solved, just ran a stock expansion chamber from a 1979 into a charcoal canister from a celica. The fuel filler neck was also replaced with one from a 1979 fj55, but the mounts had to be redone to make it fit. Now the only fuel related problem is that damn boiling fuel in my carb, gotta love the aluminum insulator on the "hi-po" manifold.
 
Joined
Nov 2, 2004
Messages
89
Whoops! Thought that was from '06....been searchin' for info on the evap sytem and vents.
 
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