Coil issue?

[m270mlrs2]

Good evening I have having an issue that the engine shuts off often 20 minutes after idle or driving. I warm up the engine before riding around but during this process, after the engine reaches operating temperature I push in the choke to let it idle on its own and after about 5 minutes it sputters then dies. I wait about 5 minutes then it starts just fine. If I immediately try to re crank it won’t start if I am driving after about 10-15 minutes and come to a stop it dies and again wait about 5 minutes and repeat the process. It hasn’t died if I am continually driving or sitting idling wit the throttle pulled out a little but it will sputter. The carburetor is a rebuild from Army Jeep Parts and it’s been on there for about 6 months. I run ethanol free fuel. The carburetor is getting fuel and everything works great like it should. I was just thinking maybe the coil is getting hot? Thanks for any advice. I just hope it’s not the carburetor it’s like the fourth one for this vehicle.

[rickf]

If you have been through 4 carburetors and you had the same issue with all of them then it is not the carburetor. You do not mention whether you have points or electronic ignition but I will assume for the time being you have electronic. It sounds like a coil issue. The best way to tell is to keep a spare spark plug with you and as soon as this happen run out and pull a wire off of one of the plugs and put it on the spare and lay that on the valve cover and crank it and look for spark. No spark then you have a bad coil or module. If you have points then that narrows it down to the coil. Now, I have seen this happen with the input capacitor where the wire comes into the distributor. Usually when that cap goes it is gone and no power gets past it but I have seen a few cases of intermittent failures.

[m270mlrs2]

Good morning it does have the electronic ignition. I will try the spark plug suggestion. The carburetor issues I have had the original was leaking all over but ran ok the other one I cracked then I had one of the newer looking ones but it ran terrible. The one on it now runs great except for the issue now which more than likely the coil but I will go though the steps with the spark plug. I think I might have another used distributor with a used coil not sure if it’s any good and try that also. Thanks again and I will keep you posted on any findings. If it is the coil any suggestions on where to get a NOS coil kit? Thanks again

[Horst]

Agree with everything said so far. Just make sure that you have a clean supply of fuel. When I got my 151, I had very similar issues as you describe, blamed a lot of things, but at the end it was clogged fuel filter. Truck did run, then stop and after waiting a few minutes it would run again for 20 minutes or so and then everything started all over.

[m270mlrs2]

I went out to check out the Jeep and look to see if I had a coil in the spare distributor and then went to pull a spark plug out of the extra engine I have. I pulled theses out of the spare engine but the doctor look like they should. Are theses just an older type of plug? Here is a photo of the best looking one and the data plate on the engine The plug has AC WR44 with MS35909-1

[Horst]

not sure what you are trying to do with those extra spark plugs, I don't think spark plugs are the source of your problem.

Anyway, typically the spark plug is a 2245 (which is the Autolite number), yours come up as 2243, so it might by a slightly different heat range?

[rickf]

He is using one of the plugs to check for spark when the engine dies to see if the coil is bad.

[Horst]

ah ok, got it, thanks! Well then almost any spark plug will work.

I have a feeling however from what I read in the first post, that it is not the coil. Why would it continue to run if the choke is pulled or throttle pushed? I think it is a fuel issue. But I was wrong before

Anyway, fuel, spark, compression, ruling out one after the other still makes sense...

[svramselaar]

hi

horst

if the mixture is rich (choke on ) the spark has a need lower voltage
wen the choke is push in the mix is leaner

it can be the coil or capacitor if points are used

sparkplugs type
if i look at a old m151 20 parts manual it stands the MS35909-1 (2243 / XMJ14/WR43/AR53 )
the `78 20 -1 parts manual stands MS35909-2 ( 2245/XMJ17/WR46/AR7S )
the 2245 are hotter range 5

i do not know wen the change is made from the 2243 to 2245

george

[muttguru]

Quick question.....

have you got an in-line fuel filter installed?
Ken

[m3a1]

I will say that what you are describing is exactly what I was experiencing when my electronic ignition was dying and I chased that particular gremlin from bumper to bumper, believing that EI's either worked or they didn't (which turned out to be an old wive's tale).

I'm not an advocate of throwing parts at anything (you are on the right track with your diagnostic process) but, with that said, if you were ever going to buy another electronic ignition module to have as a back-up, this might be a good time to get one lined up.

Cheers,
TJ

[rickf]

Ken, I will never understand why you do not like the inline filters? They are no more restrictive than the original, less so actually. Unless they are clogged in which case they have actually done their job. Which is a lot more than I can say for that tiny original filter. Remember, I rebuild these carbs and I have seen so many of them that are full of silt that has gone right through the original filters but the ones that were running aftermarket inline filters were always clean. Now, with all that said, I am not a big fan of running an inline filter between the tank and the pump unless it is deemed necessary due to crap in the tank that could damage the diaphragm in the pump or clog the valves in the pump. But I have never, ever seen an inline filter in good shape restrict the pressure or flow.

[m270mlrs2]

Good morning I ran through the checks it looked like after it died there was no spark at the spark plug but after I tried to start it up it ran good. It didn't cut off nearly as much the first day even after driving it for about an hour and it only quit while idling a couple times. I do have the inline filter and its always full of gas when running. I think I will look for a new coil and see if that helps and if anything I will have a spare.

[m270mlrs2]

I was able to find a NOS coil and Swiss Control Ignition kit. I have been starting and running the vehicle and it seems it has not acted up as much and when I started this post. It still cuts off but not as much and now it will start right away after it does quit. The exhaust also seems not to smell as bad as it did before. I am just wondering if was some bad gas or maybe the demons heard me talk about replacing parts and moved on i don't know. I guess its not bad to have a spare coil and ignition kit on hand. If it starts acting bad again, I will probably just change out those parts and see what happens. Thanks again for the tips and advice. I wanted to ask do you guys use any type of fuel stabilizer in the winter or summer? It doesn't get that cold here and I try to run the vehicle 20-30 minutes a week to keep the batteries charged and thing lubed so I don't drain the fuel. Thanks again

[Horst]

Makes me think (again) it is not the coil. Or why would it still die ?