90' GW Fuel Question (stock carb)

[stonehengeheels]

Jeep won't start without gas down the carb. When I disconnect the line running to the fiilter, put it into a jug and turn the key for about 10 seconds I don't get much more than a tablespoon or so. That seems low to me. What lb pressure should I be getting out of the pump?

[wiley-moeracing]

sounds like you are out of fuel, clogged fuel line or pick up tube, cracked fuel line that is sucking in air?

[stonehengeheels]

Had the same thought so I added 4 gals from a can. But it is easiest to check the pressure before pulling the sending unit. I was thinking 6 lbs or so.

[wiley-moeracing]

4-6lbs would be in the ballpark, but also needs to have good flow. check your fuel lines first using some compressed air while you check for noise from leaking fuel lines and noise coming out of the fuel tank( make sure you have the gas cap off when doing this. I have seen the p-up sock get plugged and have seen trash in tanks blocking the p-up tube( some plastic bag that was put in there that would at times cover the tube)

[stonehengeheels]

Thanks for the input. It was very low, maybe the lowest yet, on gas when I parked it 2 weeks ago. Maybe it did pick something up. The PO put a piece of cardboard over the sending unit opening so I at least have that going for me!

[stonehengeheels]

Here is where I am at. Pulled the sending unit and sock looks good. Black colored, is that the stock color? Still had some type of frame inside it. Easy to blow or suck through. Tested the fuel pump and got 4.5 lbs out of it. No visible hose problems. It ran fine when I parked it. Any other suggestions? I have the two outlet fuel filter, should the carb feed line be on top or does it matter?

[dkmcgowan]

maybe blow the metal fuel lines from the cab to the fuel tank, you could unhook the fuel filter and try to crank it and see if you start getting fuel pumping out, point it towards a bucket or something, sometimes the old lines will rust up and need to be blown out or redone...

[Tripwire]

you can have pressure but poor flow....probably a blocked/cracked line or the pump is shot try blowing out the lines first then plug them both at the carb with a bolt and put some air pressure in them and listen for leaks, alo be sure the filter is in the right position, the smaller line is at 12 oclock

[Carnuck]

Crud seems to get through the screen, then solidify into something that jams the inlet/outlet valves of the fuel pump open so pressure can't build up. That's the reason ALL my carbed rigs get a large TBI filter before the pump. Between the mixing of multiple additives from different stations, rust in the lines, water and who know what else gets in, fuel pumps die quicker than they used to.

[stonehengeheels]

Is that the line feeding the carb? Also is the support structure inside the pick up flat or is it supposed to be solid round like a tube? Mine was a little of both.

[stonehengeheels]

Well, I am getting fuel all the way to the carb. Gave it a few good whacks with a hammer and still no gas. I would think even with low flow (I get over 4.5 lbs out of the pump) the bowl would fill and it would run until it ran out. On to a rebuild I guess. Any other thoughts?

[Carnuck]

Crud in the needle and seat. A buddy had that problem today, so I advised him to carefully siphon gas out of the float bowl without bending the float. Then take the line off and blow air down the horn. The ball of crud splattered all over the fan, so he hooked the line back up and the Grumman van is running again. (that and the knocking noise he was going to replace his motor for was just a broken dist cap tower touching the rotor. New cap and rotor and he's rocking the giant spider truck down the road again!)

[WHSII]

I would replace all and I mean all rubber hose connections first.

Then follow each of the three steel lines looking for rust.

A pin hole in either could cause loss of flow.

[mokurt]

If it's easy to do,remove the float bowl cover.
Check to see if the fuel is going into the bowl.Also look for junk on the bottom of the bowl.

[stonehengeheels]

Well, I pulled off the carb top today and bowl was dry. Pulled the needle and seat and cleaned both, same problem. It ran until the bowl was empty. I will install the new sock from BJ's that is on the way and then see what happens. And will check the lines also.