CJ5 Won't stay running

I've used the Jeep most of this winter for plowing with no issues. I put it away with a trickle charger. I got it out seeing as it was warm (40's) to take the plow off and haul some wood. I noticed it seemed to be a little sluggish. I ran over some large icy ruts and got bounced around and the problem got worse until it stalled. After that I can't get it to stay running and it starts hard with a lot of choke and throttle. When it does run, it seems to smooth out at higher revs and then just drops to nothing regardless of throttle.

I thought fuel delivery and checked the carb float/needle, pressure, filter, everything seems to check there.

The points seem fine and everything is new in the dist. anyway. I checked the plugs and they are all dry but some carbon build up. It seems like one of the cylinders isn't firing, maybe two? Maybe a fouled plug? I'm pretty sure the generator doesn't charge the battery, would a low charged battery cause these symptoms?

It seems to be attributed to the rough driving, any other areas to look?

 

Low battery voltage could affect the ignition. This could be one part of the puzzle. Seems like there could be a lot going on here. How old is the gas and is there water in the bottom of the tank? That's where I would start, after getting the charging system up to snuff. Fuel filters are cheap. Maybe sloshed up some junk in the tank.

 

The generator should be self energizing so if it's turning it should be charging if it is still good.
Jeeps if this age are notorious for wire breaks inside the insulation, so you need a test light or VO meter to make sure you have volts in the right places.
Good luck and let us know.

 

Now that you mention the gas. I wonder if it has some water in it. I use a marine tank and after being sidetracked had left the cap off for several days prior to this. No rain or frost though. But I suppose the ethanol absorbs any moisture present. Just don't know the rate of it. The gas was otherwise fresh.

I replaced the brushes in the generator and spun it on a drill with the voltmeter. It was showing a charge for that. I also installed an amp gauge but the needle shows a slight neg. when running and the alt light usually stays on. If I rev the engine the light will falter and go out. But I don't think it is charging at the low revs that I use it. The coil wire is pretty fragile looking and about the only wire I haven't replaced yet. I'll check in to these.

 

Checked out the electronics and am getting good spark. Also put a new filter on, cleaned the lines and tank, new gas, and have good pressure. Nothing changed.

I think it's fuel starved. When the carb was open, I did notice that the needle would not fall gracefully open when the float fell without a little jiggle. I've read now that bouncing around has been problematic with the needle, float?

 

That was going to be my first guess but you said you'd checked it.

Sounds like you are getting flooding

Jeeps have special rough service float needles, and seats with a smaller intake orifice. They have different float height settings. A fuel pressure regualtor also can help.

Do some searching - there have been many posts on the topic.

 

Looked at the carb in more depth tonight. When pushing the throttle down or accelerator there doesn't appear to be any spray. So from what I researched I may have a failed diaphragm, bad check valve, or a clog. Still have to check the spark on the plugs yet just to rule that out for sure.

how would you check for a vacuum leak around the carb?

 

"how would you check for a vacuum leak around the carb?"

You can spray a little starting fluid or propane at the suspected area while idling. It will cause a change in RPM if it is sucked into a vacuum leak.

 

You said the points look fine but did you check the dewll?