Changing out fuel pump on 90 XJ with gas tank still on. Is there a trick to get the pump in with rubber seal in place while getting lock ring on? Tried few times yesterday and I am about to lower tank but thought maybe someone had a trick up their sleeve.

 

It's just a bear.

 

I run it onto ramps.
Sit in front of axle, looking at the pump.
Clean the pump seat, lock ring, and big O ring thoroughly.
I grease the pump seat and o ring, then get the lock ring just started.
I usually use a brass drift to tap the lock ring around. Go criss cross with your rotational taps. An alum tool can work too. Not sparking tools.
If its all clean and lubricated, it will reinstall.

 

Even though the O-ring should be impervious to petroleum-based products, I think using silicone grease on it might be better.

 

also consider that the two rubber hoses for the fill/vent will have to be removed (probably for the first time in 26 years) and may need to be replaced after getting them removed if dropping the tank.

 

I replaced all hoses and filter and will go out and see how it goes today, thanks for the info and ideas.

 

Dropped the tank and it was very easy plus I fished out 2 screens and a couple of rotted hoses. Fuel pump works great but gas gauge shows full all the time so crap but I will not be taking it back apart!

 

Full all time means not connected, might be the connector.

 

Thanks I will check it.

 

Now that everyone has smart things RRRRR, , anyway this pic is in the info in my signature. Gauge float might be hitting something if it's not seated right




Below is the inside of the tank. The black ring you see is the end of the cone that belongs on the end of the fuel return line on the pump assembly. That cone on the metal line holds the bottom of the whole deal in place. That should be fished out, and installed on the metal fuel return line on the assembly. Then you seat the cone into the receptacle in the tank when installing it. The fuel return and pickup are located in a tray inside the tank, so return fuel is available to be picked up at the pump inlet, even when the tank is low or at an angle.

 

I saw that cone and thought something went in it but couldn't see in there while putting in the pump so it must have missed. I assumed when the pump went into the notches that it would be in the cone right but as usual I was wrong.

 

It could be something else. I've done mine a few times, never noticed a cone. Gauge always sticks at 1/4 tank...(works below 1/4, and while it's above 1/2 or so). Stays on 1/4 for a while after fill-up. So it sort of works.

If I remove the unit and work the float by hand, it reads fine.

Next time I'll be checking that cone.

 

Pulled the tank again yesterday and made sure the rubber thingie was on the pump and then made sure it went into the cone. The gas gauge still shows just full and it stays there even if the key is off or when battery is disconnected.

I did unplug the pump and turn the key on and the gauge started going higher than full. Gauge used to work fine before I changed out the pump so any ideas?

 

A full reading all the time means an open connection to the resistive element. One end of the element sits at +12, the other is grounded, and the wiper that moves with the float simply reads the voltage; if there is no ground the whole resistor will be at the full supply voltage instead of steadily moving to 0 volts at the other end. Is there a black (or green, grey, black with white stripe etc) ground wire that isn't connected? I'm not familiar with this particular vehicle, but, they all work basically the same. The ground might go back in the wire loom and emerge somewhere else possibly grounding behind the tail light or just under the frame by the tank somewhere. Hope this helps.

 

There is a plug on the pump that connects to plug on Jeep, and I think there was 3 wires but I will check today and it used to work good until I changed out the pump. I did put contact cleaner on the plug and that didn't change anything.