75 CJ6 fuel tank question

I recently acquired a 75 CJ6. I have owned a flat fender for 25 years but have always longed for the extra space the 6's provide. One thing I noticed right away was that somewhere between 1945 and 1975 Jeep gave up on the idea of simplicity. The CJ6 came with a new tank sitting in the bed and a rotted out stock tank. I thought I would spend my day off swapping the tank to see how it would run. What I discovered is that every bolt on the jeep in the area of the gas tank has a blind side nut in an area that I can't get my fat hands into. I can't believe what a pain it was to get the old tank out and am seriously considering lifting the body off the frame to get the new one in.

Before I do that though, I do have a question. The new tank looks like the old one but filler neck is about 4 inches shorter. It is also missing the center hole on the front side of the tank (in the flange area). I don't want to jockey this up in there and not be able to get the filler hose to reach the tank. Were there two styles of tanks and/or hoses? Is it possible the new tank wasn't really designed for this Jeep? Sorry for the long post.

I will try to post pictures once I learn how to. Thanks.

 

yes I do remember 2 different inlets

 

Fesser, you can use photobucket to host photos and then post them here. You can the share the links to the photos, a photo album, or you can paste the link into the photo-link thingy here (icon on left to the one that looks like movie film) when you edit a message.

there is even a thread in the help,section on how to.
http://www.earlycj5.net/forums/showthread.php?78830-Posting-photos

I don't know enough about the tanks. I have a '5 from 69. The PO removed the ejection tank and put in a rear tank. I'm putting it back, and keeping the rear too as part of my reassy.

 

The rear mounted tank is a big improvement over the under-seat tank, and a popular upgrade for older Jeeps.

Don't take the body off. Once you get the old tank out, you have access to the mounting points and you can make them go together easy. I did it - you can too.

The tank in the bed is the wrong tank. You need the tank for your year. There are at least four styles of tank - earliest 70-72, 73-75, 76-78, and 79 on. '75 and earlier and '76 on are quite different. Post some pics.

Section 4, figure 4-5 shows the tank for your year. http://oljeep.com/edge_74_tsm.html Not everything is the same for '75 though - I suggest you buy a copy of the factory service manual.

 

Yes indeed you can get this off. I recently had to lower my tank in order to install a new bumper. With a combination of knuckles, extensions, sockets, and magnets, you can finally get it off. Take a good look at the pic that Tim posted, it might help show the mounting locations, in case you think you missed any. It is a bear, and you might end up with a colorful vocabulary during the process, but it can be done.

 

Thanks for all of the replies. I do have the factory manual. Not much help for this though. Basically says to remove the mounting bolts and brackets. Doesn't explain how to grow a universal joint in my forearm to reach the bolts.

New tank below.

 

Old tank below.




and a picture of the CJ6 the day we got home.

 

I'd guess that's a Wrangler tank, if it's Jeep. It's newer than 1980 model year. If it's the right size and shape, and the sender has the same resistances at full and empty, you could use it if you can adapt the filler neck.

New steel tanks are available, or there are plastic tanks from MTS. http://www.mtscompany.com/jeep.htm

The tech manual is written for the Jeep dealership mechanics, so they don't tell you a lot.

 

Thanks again Tim. Been shopping for tanks and the prices aren't that bad. Think I will stick with oem style. Frank

 

If it's a factory Jeep tank, there may be a part number stamped into the flange where the upper and lower tank bodies are joined together.

The neck is also most likely soldered in place.
A radiator shop could most likely swap the filler neck for you.

 

fwiw that old tank looks exactly like the one in my 74

 

I may go that route mainly because it seems the original skid plate is no longer available. I like the idea of welding the nuts onto the inside of tghe channel. My plate was so rusted that I basically broke it off at the back but I had no idea how I was going to get it back in there.

 

Mine is similar to Boyink's, but instead of welding, I used u nuts on the frame crossmember.

 

I have a 75 CJ5 that probly uses the same tank.. The new tank does not look correct. The filler pipe is too short and you will have problems getting the filler hose back on. It looks like a tank for a 76 or a 77. Also I am not sure that there is room for the collar over the sending unit to fit under the body on the new tank.

Removing the tank is the job I hate the worst on my heap.. I can tell you all about removing and replacing it.. The tanks should have a single mounting tab in the front for a bolt to mount to. The back has a hole on both corners, and is a biatch to get back together.. There is also a rubber donut thing and big washer on the inside of the corners..

Here's a few tips for this job. First jack the rear of the vehicle up and place it on jack stands.. Remove both tires and wheels.. The skid plate is separate and needs to come off first. I use a floor jack to hold it while removing it.. The screws along the back are probly going to be rusted out. I drilled em out and tack welded 14-20 nuts on the inside.

The bolts and rubber washers are the hardest to get back in.. I get the tank started and use the floor jack to help hold it up. You have to install the wires and lines while the tank is part way in.. Once you get the tank in place, just start the front bolt/nut. For the two rear fasteners you usually need a bit of help, though I have done it w/o. You can just get your hand and a ratchet, with extension into the rear corner on the inside.. Stick your hand up over the frame and down.. I usually tape the nut to the washer to the rubber gizmo. Good luck..

 

All good observations. Colojeepguy, not sure what you mean when you say you used u bolts.

 

U nuts. They "clamp" onto something like the rear crossmember channel to prevent spinning when screwing the bolt in.
http://cliphouse.com/UNuts.aspx

 

Got it. Thanks. Tank and sending unit ordered.