Farmall A diesels

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My farmall A wants to keep running when I shut it off. When it's cold it shuts off fine its just after working it a while at normal operating temp. I have tried retarding the spark and adjusting the carb. Don't know what to do next.
 
Does it have a Delco alternator? If so is there an isolation device such as diode or lamp between switch and #1 pin on alternator plug.
 
(quoted from post at 19:52:46 08/21/16) I tried it at low idle and fast. I tried turning the switch back on and off.

Low, fast don't mean a whole lot.

Slow it down to under 400 rpm and try it.

Hook up a tach or slow it till you can the cylinders.
 
I thought this topic was going to be a Farmall A That someone put
a diesel engine in.

The generator has nothing to do with your problem.

It is idling too fast.
 
you need to have everything set to spec's in including the timing. have the carb adjusted to spec. last thing to do is get it to idle as slow as it will run under 400 rpm. i guarantee it will not keep running when turned off. along with a few minutes of cool down time. you want that throttle plate in the carb pretty well clo sed so it cant suck any more gas into the intake.no fuel ... no fire! that is all there is too it.
 
If slowing the idle down didn't stop it, an easy way to determine if it's still getting spark is to turn the ignition off, pull the coil wire, see if that stops it. If so the switch is not killing the power (if battery ignition) or providing the kill ground (if magneto). Either case, look for corrosion on the back of the ignition switch.

If pulling the coil wire doesn't stop it, it's not running hot, and slowing the idle, and checking the timing didn't fix it, could be the cylinders are carboned to the point it is running on heat, compression, and glowing carbon. Only sure way to clean it is to pull the head, scrape it out.

Personally, unless it's detonating (clattering under load) I would just kill it with the clutch.
 
no such thing... it can run on heat, compression, and glowing carbon, alone. it is sucking fuel past the throttle plate. you have to remove the fuel by closing the throttle plates. dont need to pull the head. just mist some water into the intake on a fast idle. that will clean out all carbon. a diesel will not even run without fuel.
 
JohM,
Shutting off the gas is what I was going to say. Instead of turning gas off my hand, I have 12v gas solenoids in my Farmall C and Jubilee because the carbs will drip.

I have a 20 hp kohler and 20 hp Honda that likes to diesel. I pulled the kill wire from Ingition coils and turn the power off to the carb. The carbs have a built in solenoid. In a few seconds they shut off no dieseling.
 
Adjut the point gap. I worked for an old Okie that when his chevy trucks would get to diseling he would just adjust the points a bit. That would stop it on the next running. He said that was why they would do that. I guess it must be a chevy thing. I have never had problems with gassers doing that. then
I never liked a gas engine and all the nonsense that went with them.
 
Okay, two questions:

1. How would adjusting the points have any effect? The ignition is OFF.

2. Why is "dieseling" a problem?

The long and short of it is you've got carbon deposits in the engine that are getting hot acting as ignition sources and causing the dieseling. Adjusting carburetor, timing, plugs, wires, sacrificing a live chicken... None of that is going to fix the problem. If you want it to truly stop you need to pull the engine apart and clean out all the carbon deposits.
 
I am sure it is the carbon build up. I have tried everything else. It would be great if I could clean it without a tear down. Thanks for all the input.
 

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