Fuel tank issues.....

Ok so I put a stump sized dent in my gas tank a few months ago. I went to a yard and got a replacement from a 87-90 xj 4.0L So now my fuel gague is not accurate and it will not hold the same ammount of fuel. I am assuming I have a lower capacity tank. Are these convertable like the tj ones or do I need to find the full tank? Anyone know what is up with my tank?

I ran into the same issue, but after taking the tank apart I couldn't see a way to convert it like the YJ tanks. The vent tube seemed to be in the same spot as my older larger tank. I found a steel replacement tank for sale on ebay for 79.99 with free shipping. Works great, but doesn't have the little pan baffle thingy by the pickup tube. So I have to fill up the tank just under 1/8th of a tank or it sputters sometime when I turn.

I am not sure about this but, my 87 has an optional high capacity 20 gallon tank. I know that it was optional in 87, but I am not sure if they ever standardized it. If so that yes u may have a smaller tank.

What amazes me are that the outside looks exactly like my 84 tank. So I figured there was some type of baffle or something in there.

The fill neck extends down further into the tank on the "smaller" tanks. The big ones have a hole near the top of the fill tube near the top of the tank that the others don't. (allows air to come out) It was an emissions/fill thing for areas where alcohol blended fuel is more common.

carnuck said:

The fill neck extends down further into the tank on the "smaller" tanks. The big ones have a hole near the top of the fill tube near the top of the tank that the others don't. (allows air to come out) It was an emissions/fill thing for areas where alcohol blended fuel is more common.

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So can I convert mine to hold more? If so what do I need a hole in the fill tube in the tank? That sounds scary.... :explosion

Ok, so here is the skinny on the early tanks in the none HO XJ's. There is a pan in the tank that keeps the gas from getting to the pump. It looks like one of the aluminam pans you buy to bake a turkey in. Bassically the pump and sending unit is inside this small pan that is attacked to the tank. It keep the extra gas from gettign to the pump. I took a new pry bar and poked holes in it so the gas could get to the pump. No :explosion and it appears to be running fine.