YJ Starting then stalling! several things replaced

djemalo

New member
Hi guys,
Wrangler YJ 1989 4.2 carter bbd carb, only a few months old.
I have searched around the web and have found none that will work for me...


Basically it tries to crank but doesnt turn over. Starter is working as it should, battery is fine, carburetor is not that old and in fact i have rebuild it in search for a solution last night. THE ONLY WAY IT TURNS OVER is when poured a little gas in the carb, then of course it dies a few seconds later when the gas is burned up. ANOTHER thing is when i pump the accelerator no fuel is being injected into the carb. I disconnected the line before the filter to see if any gas is coming through but it is dry.


Note:
I changed fuel filter, rebuild carb, checked the float level to 1/4", check for kinks on the fuel line, changed alternator, and belt, and fuel pump was replaced.


It should be getting spark since the car does turn on when gas is in the carb right?
 
Defin. fuel in the tank, about 4-6 gallons. So should i get another mechanical pump or maybe i should invest in a electrical one.
 
If you just replaced the fuel pump and you still don't have any fuel flow I would check the tank sending unit. Also, if you do decide to install an electric fuel pump be sure to install an inline fuel pressure regulator.
 

Detach the feed line to the carb from the fuel pump then have a friend turn the key "ON" position with out cranking. During the first several seconds in the ON position the fuel pump should prime and pressurize the line therefore you should get fuel to come out of the detached end you should also hear a faint "buzz" of the pump working during those first couple seconds. If this does not occur check to see if the fuel pump is getting power. If it is, then the pump is probably bad.

Bacon
 
I would remove the pump and make certain that the lever is under the cam lobe and not sitting on the top. It would be tuff in install it incorrectly, but it's possible. Do you have the old pump (you mentioned you replaced the pump)? You could try re-installing the old one just to see if your pumping fuel? You should also be able to draw fuel through up to the pump with the line removed from the pump. Just use a piece of hose to syphin the fuel, but be careful and go slow.
 
Detach the feed line to the carb from the fuel pump then have a friend turn the key "ON" position with out cranking. During the first several seconds in the ON position the fuel pump should prime and pressurize the line therefore you should get fuel to come out of the detached end you should also hear a faint "buzz" of the pump working during those first couple seconds. If this does not occur check to see if the fuel pump is getting power. If it is, then the pump is probably bad.

Bacon

I have a mechanical pump, no electrical pieces run or connect to it. But i will try seeing if anything is coming out when i try cranking it

To the first guy, The sending unit will be located inside the tank yes? or outside around it somewhere
 

I got a container with fuel and ran a line from the fuel to the pump and it turned over, kept going until of course the container ran out of fuel. So at least we know everything is working as it should except before the pump!

So i am going to assume that there is a leak or restriction on that line ? or perhaps there is a sending unit for these vehicles (89 4.2l I6) that i dont know about somewhere in the tank? Or is the fuel system strictly mechanical....
 
you might have a hole in the line between the pump and the tank and the pump is just sucking air through the hole? or maybe the pick up in the tank and a hole and its trying to suck air from in the tank?
 
Hmm It was suggested to me to suck the fuel manually from the supply (line to the tank) and see if i can get it to flow. I will try that and update. If i see any leaks then there is air coming out of the line so i will replace it.
Thank you guys for replying, so amazingly fast lol.
 

Have you verified its not he CPS or CKP?

Crank
Spark
Fuel


Another item to check is prime. By turning your key on and off three times waiting 3-5 sec between in the on position. Thn try starting.
 
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I would take the pump out and put back in. Does the pump have a return line, could the lines be hooked up backwards?
 
The line from the tank to the pump is just a rubber fuel line. I will be removing that today and check from air leaks or obstructions inside of it.

And about the Crank spark Fuel, i have confirmed this by using a bottle of fuel being sucked in from the pump with another rubber line instead of the line from the tank. The car stayed on for a while until the gasoline ran out of the bottle.
 

have you driven this jeep before? reason I ask is could the previous owner have the fuel line hooked up wrong at the tank (wrong outlet). It has to be the tank (rusty inside and clogged), lines, or the pump, its not your carb.
 
Okay well i didnt drop the tank, instead i made a square hole on the floor and accessed the sending unit that way. The filter was old and brittle and broke apart by touch so that has to be replaced. The fuel gauge never worked so the sending unit will have to be replace..


Now for the weird part, NONE of the hoses or metal fuel lines, or the lines on the sending unit itself were clogged up with anything. The sending unit screen could have been clogged but i just dont see anything out of the norm that would. I threw the filter away and put the unit back in the tank without the filter, tried to pump the fuel to the carb and nothing--then tried cranking the vehicle, nothing. So with and without the filter it is not picking up any fuel. (tank was 80% full by the way).


Any other things that could be happening?
 
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