2N quit on me

[Ray Graham]

Plowing snow yesterday and she stalled just as I finished. Put her in the carriage house to mess with today, but this morning she fired right up. Started plowing some more, but 1/2 hour in she started spitting and sputtering and then backfired a little and died.
Fuel:good
Spark:good
Any Ideas on what I am missing?
Thanks

 

[wwildhorse2k]

Snow or water in the distributor ?

 

[Ray Graham]

Nope, has the 6 volt system all nice & dry with no cracks or corrosion.

 

[Jim in Western MI]

Though no experience snow plowing down here in eastern NC, I've had similar events when bushhogging tall weeds (8 foot tall dogfennel, etc.) when raining or early morning and very dewy. Every now and then one would slap over onto one or more sparkies and ground it out and/or wet the distributor down good..., leading to misses and putts. Sometimes a brier will jerk a plug wire off. I expect snow and dampness could do the same, excepting the loss of a plug wire...

 

[ford5600]

could have had water in the gas and froze in the bottom of the carb. or you had freeze over of the carb. thats when the gas is extremely cold and it freezes the outside of the carb. effecting the performance.

 

[old]

Back fire a lot of times say fuel flow problem. Float could be sticking but not likely. Might be your ignition switch going bad but then the spark is good or so you say. So your spark is a blue/white and will jump a 1/4 gap?? As for no cracks how do you know your cap is not cracked?? Distributor caps crack and you can not see the cracks and that is enough when hit by a little water to cause major problems

 

[Bruce (VA)]

"Fuel:good
Spark:good"

Nope, check again.

It takes three things for an engine to run: spark at the right time, compression, & fuel in the right mixture.

It didn't lose compression & stop. You have a fuel problem or a spark problem. Next time it stops, check quickly for fuel then spark. When I say quickly, I mean get off the seat, grab the tools & do it right then. There are ways to check for spark & fuel that work & ways that don't. For example, having gas to the carb is nice, but having it past the float is what counts! That’s why removing the bolt in the bottom of the carb is the way to do it. And, same thing w/ spark at the plugs. Some folks think that checking for spark means pulling a plug wire off & looking for one. Well, it's the distance the spark jumps at the plug that gives you the info you want. It takes about 17kv to jump a 3/16" gap & 22kv to jump ¼” in the open air, so that's why you need to use a spark plug. Or, a store bought plug checker. Remember, it’s 14psi outside of the engine & about 90psi at a 6:1 compression ratio in the cylinders & compressed air creates electrical resistance, so you really need the 17-22kv to fire the plugs when the engine is running.
50 Tips

 

[Ray Graham]

I did the check with the spark plug as you describe in the 50 tips, as I read it and used it prior to posting, and yes it covered the gap. I pulled the plug out of carb and fuel ran out freely.
What are the other possible culprits? Timing, points??????????

TIA

 

[maplehillfrm]

I wouldnt say that it is NOT your points or timing, but once they are out of whack they stay out of whack,,, they dont "repair" themselves,,

I would stick with water in the dist or coil,, or a iced up carb,, when it stops look at your carb and see if she is frosted over, I have had that a few times when working mine hard plowing,, but havent used it in a few yrs for plowing, I do it from the comfort of my truck now ,, I know its cheating but so much nicer ,haha

ar eyou sure its a 1/2 hr and not longer ,, could possibly be your coil,, next time it stalls see if you can jumper your ignition relay,, I have had that go on me too, good luck,pat

 

[Bruce (VA)]

Your points & timing aren't going to be ok for 30 minutes & then go bad.

As soon as it stops, you need to check for spark. A 30 minute run time could be the coil & less likely, the ignition switch.

Coil problems are difficult to diagnose. For starters, round coils are pretty robust & square coils aren’t (because of the difference in insulation used), but neither one will hold up to a poorly done 12v conversion that allows too much current to the coil. Too much current creates heat which melts the insulation. There are a few ways to see if a coil is bad, but it’s not possible to determine if a coil is good w/o some expensive testing equipment. If you detect a dead short or high resistance in the coil w/ an ohm meter, it’s bad. If it’s cracked, it’s bad. If a sidemount coil w/ battery voltage to the primary will not jump a ¼” gap from the secondary wire to the block, it’s bad. But, here is the hard part: even if you do not detect a short, even if it will produce a spark, even if it’s not cracked, that doesn’t mean the coil will work when it’s hot & under a load. So, it’s a process of elimination. If the tractor starts & runs fine for 30 minutes or an hour then cuts off & refuses to re-start, and you checked for spark at the plugs & it had no spark at all, AND you have the correct voltage at the coil that’s a good sign that you have a bad coil. Let it cool off, restart it & if you have a good spark, odds are it’s a bad coil. But, even then, you might end up w/ a spare coil on the shelf!


Are the gaskets ok?
50 Tips

 

[Ray Graham]

The gaskets seem to be ok, except for very back exhaust gasket. Has some smoking going on around it.

Thanks