Stalling could use some help please

[Cjordan]

1982 CJ7 , AMC 258 i6 / 4.2l , MC2150 carb is electric choke but I'm not certain it's working properly.

I haven't cranked this thing in about a month and a half to two months, when I parked it up last time it was running fine. Got in it today and it took a little bit to get it fired up. Once it was running it idled fine but didn't want to run once I started coming off the clutch.

Messed around with it and finally babied it to the front yard to mess with it.
In neutral you can give it about 1/4 throttle and it's fine or you can ease a past that and you can get to about 3/4 throttle and it may or may not run without spitting, sputtering and trying to die.
I've taken it down the road to try to run it a little bit, but you can't get over about 1/4 throttle before it starts acting up and trying to back fire.

The guy who set the timing done so by ear back during the early summer. I put a timing light on it earlier and it was at about 22deg. I've backed it down to 8 or 9 deg and it's doing the same thing.
I've noticed that when you hit the throttle the vac advance works, but when checking the timing with a light it doesn't matter if the vac advance is hooked up or not the timing stays the same. Also when you unhook the vac advance it doesn't matter if you plug the hose or not it idles and revs the same. I'm about out of ideas so I'm hoping someone on here can point me in the right direction

 

[mtnwhlr]

Did you pull the top of the air cleaner off and check to see if the choke is open?

 

[Torxhead]

You might just have some bad gas or water from condensation that could have got in the tank. Sometimes electrical componets can go bad like the ignition control module or distributor pick up coil, but that is after you have checked everything else, especially if it has been sitting outside. CJ distributors seem to have a slow advance curve so you might check with a timing light with more rpms. Do the easy stuff first before you start spending money.

 

[Cjordan]

Did you pull the top of the air cleaner off and check to see if the choke is open?

Yes sir it's open, I had forgot to mention that a couple times I stuck my hand over it while reving the engine. It would pull real hard on my hand and sounded pretty good until I would pull my hand off then it would start trying to die.

 

[Cjordan]

You might just have some bad gas or water from condensation that could have got in the tank. Sometimes electrical componets can go bad like the ignition control module or distributor pick up coil, but that is after you have checked everything else, especially if it has been sitting outside. CJ distributors seem to have a slow advance curve so you might check with a timing light with more rpms. Do the easy stuff first before you start spending money.

I had noticed the sticker by the radiator said check idle rpm's at 650 and high idle at 1400 I believe it was. Since I'm not running a carter carb anymore with 6 miles of vacuum lines do I still need to check it at 1400? Heck it might have said 1650 can't remember now to save my life. Anyhow which ever it says is that what I should check it at, or what would y'all suggest?
It has been outside but under a shed, although the shed has really high open walls.

Something seems off tho for it to idle and respond the same on both 9deg and 22deg, with or with out the vac advance hooked up, and when the vac advance is unplugged wheather you plug the line from the carb or not still the same

 

[coldair]

I had noticed the sticker by the radiator said check idle rpm's at 650 and high idle at 1400 I believe it was. Since I'm not running a carter carb anymore with 6 miles of vacuum lines do I still need to check it at 1400? Heck it might have said 1650 can't remember now to save my life. Anyhow which ever it says is that what I should check it at, or what would y'all suggest?
It has been outside but under a shed, although the shed has really high open walls.

Something seems off tho for it to idle and respond the same on both 9deg and 22deg, with or with out the vac advance hooked up, and when the vac advance is unplugged wheather you plug the line from the carb or not still the same

Sounds to me that your choke isn't working right. Or you might need to clean your carb.

 

[Cjordan]

So... not much of an update, but here's what I've found so far. Hopefully this will ring a bell for someone because it sure has me stumped.

I've tried three different sets of spark plugs
The timing has been anywhere from 8deg-22deg
Doesn't matter if you have vac advance hooked up or not timing stays the same after you hook it back up and the jeep acts the same wheather you time it with or without the vac advance hooked up
I've pulled the carb off and cleaned the jets, and float the best I could with carb cleaner

I took it for a ride today and put some fresh gas in it in hopes it would get better but it didn't.

Doesn't seem to matter what I do or what adjustments I make, this thing will idle somewhat ok, up to about 1/4 throttle it does good, anything past 1/4 throtle it wants to spit, sputter, and bogg down.
With that being said you can go to 1/4 throttle then work it a little at a time and get to full throttle, but it won't last long till it starts falling off again.
Unless you choke it by placing your hand over the carb then it does alright no matter how fast or slow you hit the throttle.

Also if your driving being easy on the throttle when you let off it sounds like it's backfiring through the exhaust sometimes.

I'm at a loss and could use any help y'all can give.

What's aggravating is this thing set up for a year and a half due to Transmission issues, got that fixed it was doing good parked it up for a month and a half and now she doesn't want to run.

 

[Lumpy Grits]

See what readings you get at warm idle with a vacuum gauge?
Are both idle mix screws on the carb set the same?
Check ALL the bolts etc on the carb base and intake manifold.
MC2100 series are well know for base vacuum leakage.
Ck for it with some very soapy water in a spray bottle.
LG

 

[coldair]

Do you have a way of seeing what kind of fuel pressure your getting sounds lean if it will run with your hand over the carb.

 

[mtnwhlr]

What's aggravating is this thing set up for a year and a half due to Transmission issues, got that fixed it was doing good parked it up for a month and a half and now she doesn't want to run.

With it sitting this long with the crappy gas we get these days if it had started to go bad it can cause the fuel pump to not work right and sticky valves for starters.

 

[Cjordan]

See what readings you get at warm idle with a vacuum gauge?
Are both idle mix screws on the carb set the same?
Check ALL the bolts etc on the carb base and intake manifold.
MC2100 series are well know for base vacuum leakage.
Ck for it with some very soapy water in a spray bottle.
LG

Put a vacuum gauge on it this afternoon. Let everything get up to operating temp. Unplugged the vac advance and put a cap over the carb port "that I'm using for vac advance"

Can't remember what the vac gauge reading was when I started but according to the timing light it was at about 9-10deg, but after messing around with the timing, and adjusting the carb the vac gauge is reading about 19, timing light reading about 23-24deg. At one time it was up to about 22in, but the engine had a real bad miss so I backed it off to 19.
This is idelig at about 650-700.
I didn't use soapy water to check the base plate, but I did spray starting fluid over all vac lines and around the base of the carb. It never did clear up any while doing this so I'm assuming I don't have a vacuum leak, unless I'm missing something.

This thing has a horrible miss to it, I pulled each of the plug wires one at a time and it started running rougher with each one as I unplugged it.

I haven't checked my fuel pressure yet, hopefully I can do that tomorrow

On the carb adjustment screws I have them backed out about 2.5-2.75 turns, with both being as close to the same as I could get them. I had em out to three turns each but I could smell gas out of the exhaust pretty bad.

One thing I'm not for sure about and maybe someone here can steer me in the right direction. As I was making adjustments on the carb I never really noticed the needle moving on the gauge, it did go from 19-20 at one time but I think that's when I was about three turns out.

Short story long jeep is still acting and responding about the same.

One other thing maybe I've already mentioned it so sorry if I'm repeating my self. If you go to WOT and hold it till it dies from stalling out, you can pump the throttle all you want but you won't get any gas out of the accelerator pump, until to turn the engine a few times, then it'll go back to pumping gas.

Another thing I noticed today, when the jeep was sitting level it had no problems starting, but once I backed it up some sitting on a hill "a little bit lower in the back" it didn't want to start without pumping and pumping several times and turning it over several times.
Don't know if that might help with anything or not.

Sorry to be so long winded on all of this just trying to make sure I explain it all the best I can, so for hose of you who don't fall asleep while reading this I do greatly appreciate any and all help you can provide.

Bout the only thing I haven't tried is a new fuel filter. I know I probably should have tried that first, but when I pulled it off the gas came out pretty dang clear

 

[Torxhead]

Another check you could do would be to pull the spark plugs to check the burn rate on each plug.

 

[Cjordan]

Another check you could do would be to pull the spark plugs to check the burn rate on each plug.

Just put a new set in ran it for a minute or two pulled one out but it was still clean so I'm gonna have to run it a little longer maybe drive it around the yard some.

So far new plugs, new fuel filter, checked for vac leaks "none that I can find", adjusted timing, adjusted carb, cleaned carb, but it still acts the same. Bout all that's left to try is to put a fuel pressure gauge on it to see what kind of pressure I'm getting. Runs fine on high idle though which is about 1500rpm

I'm not fimiliar enough with carburetors, but figured I'd run something by y'all to see if his is right or not.

While watching the vac advance while easing into the throttle it's working up to the point where the engine starts falling off then the vac advance "lets go" then stars working again as the engine starts picking back up.

I'm assuming that's because when the engine starts stalling it looses all vacuum but that's just a guess

 

[Kane]

Her are a couple things to check.
The stock carb fuel filter has two outlets and one if for the return line to the tank. Make sure the return line exits the top of the filter.

The fuel bowl float could have a hole in it and this will cause the float to drop in the carb which shuts off the fuel supply and will cause a low fuel condition in the carb. This will also show up when you pump the accelerator and you do not see any gas spurting.

This float could also improperly adjusted and be sitting too low in the bowl.

Inside the inlet of the carb there is a brass screen. If this is clogged then you are starving for gas. Check this and clean it.

If the fuel pump is failing from a torn diaphragm then you have too little fuel pressure and this will also cause the carb to remain empty.

In a worse case scenario you also have a fuel sock on the sending unit in the gas tank. If this tank had bad dirty gas in the past, this sock could be clogged causing a low fuel conditions.

 

[Cjordan]

Her are a couple things to check.
The stock carb fuel filter has two outlets and one if for the return line to the tank. Make sure the return line exits the top of the filter.

The fuel bowl float could have a hole in it and this will cause the float to drop in the carb which shuts off the fuel supply and will cause a low fuel condition in the carb. This will also show up when you pump the accelerator and you do not see any gas spurting.

This float could also improperly adjusted and be sitting too low in the bowl.

Inside the inlet of the carb there is a brass screen. If this is clogged then you are starving for gas. Check this and clean it.

If the fuel pump is failing from a torn diaphragm then you have too little fuel pressure and this will also cause the carb to remain empty.

In a worse case scenario you also have a fuel sock on the sending unit in the gas tank. If this tank had bad dirty gas in the past, this sock could be clogged causing a low fuel conditions.

Thank you sir the return line on the filter is in the 12 o'clock position, but I will pull he carb again and check the other things you had mentioned. When I cleaned it I didn't notice a hole in the float but I wasn't looking for one either. I didn't notice a screen. Would this be where the fuel line comes in?
When I cleaned the carb, I left it bolted down on the intake, tore the top half off and cleaned everything us best I could that way. It's a MC2150 so I'm not for sure which jet this is but the one on the passenger side of the engine, I couldn't get it out, seemed like the harder I tried the screwdriver wanted to slip/strip away, so I shot some carb cleaner through the hole.
The float didn't appear to be sitting level (without fuel in the bowl) but I didn't have a way to check it for sure at the time.
For it to have been running fine a month and a half ago is there something that could have caused the float to not sit level now? Sorry if that's a dumb question, just trying to get my head wrapped around this.
I do appreciate the advice I will get back on it tomorrow

 

[Lumpy Grits]

Are you SURE, the spark plug wires are attached in the correct order on the engine and dizzy cap?
If you haven't yet-I would go to a NAPA store and get the top of the line dizzy cap, rotor and wires. I also suggest Autolite 985 spark plugs set to .035" gap.
Did you ck the 2 idle mix screws on the carb?
Give the soapy water a try-It works very well for hunting vacuum leaks.
BUY a timing light. You want inductive type.
LG

 

[Cjordan]

Are you SURE, the spark plug wires are attached in the correct order on the engine and dizzy cap?
If you haven't yet-I would go to a NAPA store and get the top of the line dizzy cap, rotor and wires. I also suggest Autolite 985 spark plugs set to .035" gap.
Did you ck the 2 idle mix screws on the carb?
Give the soapy water a try-It works very well for hunting vacuum leaks.
BUY a timing light. You want inductive type.
LG

Yes sir I checked the wires against the firing order
(Cap and button from NAPA with the brass nipples
Autolite #985's set to .035) all your suggestion from a couple years ago when I bought it and was having some issues
The timing light I have had pos-neg leads with a clamp that goes around the number one wire and flashes I'm guessing that's the kind I need
Sprayed all the vacuum lines, and all around a he base of the carb with soapy water but it didn't stall out ( assuming that's what I was supposed to be listening for) I had never heard of nor used that method till you recommended it so after a quick google search they said the engine would stall when it sucks he water in. Is that right?

Just doesn't make any sense it was running fine then crank it up one day and having problems out of the blue

Bout the only thing I haven't changed is the fuel pump, runs fine on high idle which is about 1500 rpms

 

[Hedgehog]

Haven't been here in a little while. But while looking at your problems and the things you've done to try to repair it what occurs to me is that you've probably wasted a whole bunch of time. The spark plugs won't spontaneously go bad, your timing won't change around, the spark plug wires won't jump around to different plugs by themselves. Adjusting the jets only effect the idle and your 2150 is working well at idle.

There are two fuel related possibilities and one very unlikely ignition possibility.

What jumps right to the top of my head is that your engine dies when transitioning from the idle jets to the mid and high speed jets. Since you changed your fuel filter fuel flow should be unrestricted so your jets are likely fouled you will need to take the thing OFF the engine and either rebuild/completely clean it your self or spend some money to have a pro do it.

The other fuel related problem could be related to your fuel pump. both mechanical and electric pumps have a habit of working well one minute and not working well the next. I believe they are likely failing slowly to the point where they don't produce the pressure needed to run your engine properly. Both mechanical and electric pumps are relatively easy to replace, messy and slightly frustrating but easy enough.

In the odd chance your problem is electrical. Well, do you have an HEI ignition, a solid state of some sort or an MSD. These can fail spontaneously, but that is usually heat related, heat will break down a failing distributor module. I very much doubt your engine is getting hot enough to cause the failure you are describing.

I'm betting that your carb. is the problem. As was stated before modern fuel will go bad very quickly. Keep in mind there are several different jets that do different things at different engine speeds. Putting your hand over the carb forces your idle jets to pull more fuel than it's designed to do and your jeep will never run well like that.

 

[Lumpy Grits]

That's why I said to confirm your idle mix settings. Do you know how to do this?
Your FP is fine-Stop throw'n $$$ at it till you know what the issue is.
BTW: Unless it's a really bad vacuum leak-The soapy water just bogs the engine a bit. What you want to watch for, are the bubbles being sucked in.
LG

 

[Lumpy Grits]

One other thing-
Take the cap off the gas tank, and see if there's any change.
LG