Has Anyone Had Gas Tank Mount Issues?

So our rear mount gas tanks are mounted at 3 points; the two in the back corners, and the one centered up front. My question is if anyone has had issues with the front one. Mine cracked right off the tank, but it also looks like my tank was installed without the rubber washers. I got thinking, and from what I've read gas weighs about 6 pounds per gallon, putting us around 90 pounds for a full tank! The mounting doesn't look very substantial when considering that. I bought a new tank as I'm in a rush to finish my project to enjoy for the rest of summer (I'll fix the old one later), I'm wondering if I should reinforce that area before I paint and install it

 

It’s absolutely fine, in theory the same fasteners (nut and bolt) hold your engine in place..

 

I have not seen breakage such as you describe.

You have the factory skid plate? The gas tank skid plate was optional, but I've only recall one Jeep from this era where it was not present. Originally there was a pad between the skid plate and the tank that would help support the tank. There are rubber insulators on the brackets - the tank sits on top of the brackets, and the insulators go on top of the tank steel between the fender washer and the tank steel.

The problem with the pad was it soaks up water and the bottom of the tank rusts. On my current CJ-6, I left it out, but I think today I'd figure out some substitute and glue it to the bottom of the tank, to help support the tank and still keep water from getting to the bottom of the tank.

You could also switch to the '76-up style, where the skid plate is no longer optional and is used to support the tank. Should fit - that tank and skid fit ok on the early CJs, so it should also work on an intermediate.

 

Tim's idea has me thinking of that aerosol foam used on front underside support of hood. Kind of a rubbery version of Great Stuff foam. A blob under four corners should provide some support. Put heavy coat of car wax on either tank or skid plate so it isnt permanently glued together.

 

I do have the skidplate too, and maybe ill figure out a good way to use it to add additional support eventually (without resorting to foam). Anyways it sounds like I'm good to put it together without worry of it happening again! I appreciate the input.

 

I'm dumb but I found the problem. My bracket was a bit special so today I made a proper one that looks more like the one in the factory diagram. I didn't even think about the weird shape when I dropped it off with some others to get powder coated. I wonder what the story was That said I still think the tanks mounting points look thin, but I think I'll be fine now!

 

Both of those mounts are “factory”
More square one is 71 and earlier. Z one is 72-75 from what I’ve seen

 

The Z type is what I have on my '75. The '72 TSM, '75 TSM and the '74-80 parts book all show the square type. However, that may be due to Jeep's habit of recycling drawings from year to year, even if the drawing isn't 100% accurate.

 

my ‘75 has the Z, and no tank skid plate.

 

Wow thats interesting! I wonder what prompted the redesign? What do you guys think is better?

Im learning more every day about these jeeps!

 

My 73 has the Z.

 

More than likely it was a cost thing or the vendor changed either one works fine.

 

Or faster on the assembly line. I guess that's a cost thing, indirectly.

 

Well I switched back to the Z. The C mount looked like it might contact the diff under full suspension compression. Maybe it would be fine but I wanted to play it safe. I don't think my springs are factory so it could just be my setup (axle location) specifically, but I'm thinking that AMC might've changed the bracket to give that slight clearance increase when they switched to the centered-pumpkin axles.

 

I'm changing out the tank on my 75 because it's full of sludge and varnished gas. Does the front lip of the tank get bent up or down for the z bracket? I suspect po put the z bracket in flipped around on mine so was curious how other people's looked. Mine was bent up on the old tank and it's impossible to get a wrench on the bolt head that way to loosen/tighten the nut on mine.

 

The front lip bends up, and then I have a ~5/8" thick rubber spacer between it and the bracket. I also put another rubber spacer on the other side of the tank to hopefully allow a little more flex and pass less vibration.

 

Great info thank you.

 

Z type on mine. One of the things I really hate about working on my heap. That mount. And dropping the gas tank in general.

 

My new to me 74 had a 20 gallon composite tank and skid plate installed. Didn't care for it much because the tank hung lower than the spring shackles. And the composite tank leaks around the sending unit.

So I ordered a stock 15 gallon tank, sending unit and rubber fill kit. Fortunately the original z style tank hangers were still there on the frame. Looks like I can cut down the 20 gallon skid plate and mount it up close to the tank. The composite tank sat directly on the skid plate, but had a thick layer of foam wedged between the tub and the tank.

I bought some nylon washers to isolate the tank from the hangers, now just need to figure out what to use between the tank and skid plate. I'm thinking maybe using a thick rubber mat from the hardware store instead of the spray foam mentioned earlier in this thread.

 

What am I missing? Why would you want the new (metal tank I assume) isolated from the hangers? Don't they aid in electrically grounding the tank to the jeep itself?