My cj keeps shutting off help!!!

[Micah Chambers]

I have a 87 cj 7 with inline six. What it's doin is when it warms up after about 15min when I'm driving and slow down then give it gas to go it shuts off. It will crank right back up but it does it every time. What I have done new 4brl holly carb new plugs cap button fuel lines and new pcv valve and new vacuum lines. Any suggestions

 

[JPNinPA]

Shuts off as in dead not idling down or hesitating... How clean and tight is your battery and ground connections?

 

[Micah Chambers]

Shuts off as in dead not idling down or hesitating... How clean and tight is your battery and ground connections?

Yes it goes completely dead. And cables are clean and tight.

 

[JPNinPA]

Rotor and cap cracked?

battery alt. and ground issues will cause it to die.

 

[Micah Chambers]

Rotor and cap cracked?

battery alt. and ground issues will cause it to die.

New rotter and cap. Ground issues will cause it to go dead when I accelerate??

 

[Catoctin Jeep]

When the power valves blow on the Holleys your engine will go dead when you let off the throttle. The fuel / air mixture goes very rich. Did your engine ever backfire through the carb. If it did it usually takes out the power valve.

 

[Micah Chambers]

When the power valves blow on the Holleys your engine will go dead when you let off the throttle. The fuel / air mixture goes very rich. Did your engine ever backfire through the carb. If it did it usually takes out the power valve.

It's a brand new carb I just put it on yesterday hoping to fix this problem. No no back fire

 

[808CJ7]

What size carb. are you running?

 

[69jeepcj]

check your float level, there should be a large flathead screw on the passenger side float bowl. pull that out and the fuel should be right at the bottom of the screw hole, if you shake the jeep the fuel should trinkle out. If you have to set it, on top of carb float bowl there is a flathead bolt with a nut under it. loosen the screw and turn the nut (I believe counter clockwise) to raise the fuel level.
Did you check for vac leak at the carb base.?
Just to clearify, 86 was the last year for the cj.

 

[Micah Chambers]

check your float level, there should be a large flathead screw on the passenger side float bowl. pull that out and the fuel should be right at the bottom of the screw hole, if you shake the jeep the fuel should trinkle out. If you have to set it, on top of carb float bowl there is a flathead bolt with a nut under it. loosen the screw and turn the nut (I believe counter clockwise) to raise the fuel level.
Did you check for vac leak at the carb base.?
Just to clearify, 86 was the last year for the cj.

Ok I'll check that. And sorry it's an 83 my bad.

 

[Micah Chambers]

What size carb. are you running?

600 cfm

 

[808CJ7]

600 cfm

What's your timing set at and is your vacuum advance working? I know people will disagree with me, but I think 600 cfm is to much for a stock 4.2 considering that they came from the factory with somewhere around 280 cfm.

 

[Catoctin Jeep]

I'm just throwing this out there, but did you set the idle. If the idle is set to low that could be another issue.

 

[PoliceMonkey161]

If it were me, I would pull my plugs before I went too much further. I would be looking for consistent coloring on all six around the electrode and gap. Additionally the coloring, whether black (rich) or more tan-ish (lean), would give a fair indication of a fuel delivery issue, spark or other problem.

 

[flatie46]

What's your timing set at and is your vacuum advance working? I know people will disagree with me, but I think 600 cfm is to much for a stock 4.2 considering that they came from the factory with somewhere around 280 cfm.

If I'm not mistaken CFM's are measured differently on 4bbl than on a 2bbl. Although I can't dissagree, it may indeed be too much. I've never tried to run a 4bbl on a 6cyl.