200 only sparking on one cylinder

(quoted from post at 13:28:02 09/05/12) I've got a 200 that that is very hard to start, runs rough and has little to no power. I went through the fuel side and replaced many parts on the electrical side with no improvement before doing some actual trouble shooting. I gapped a spark plug to 1/4 inch and tried it on each cylinder. Number one had a nice spark and all others showed no spark. The engine only tries to start with #1 wire attached.

The points and condensor are new as is the coil, rotor and, cap. Plug wires look good. I pulled the rotor and cap and watched the points while cranking the engine. They don't appear to hit evenly on all four cylinders. It seems like this could be causing my lack of spark, but I'm not sure why the points whouldn't be striking evenly. Anyone seen this before or got a better explination for my lack of spark?

Thanks

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(quoted from post at 14:13:23 09/05/12)

(quoted from post at 13:28:02 09/05/12) I've got a 200 that that is very hard to start, runs rough and has little to no power. I went through the fuel side and replaced many parts on the electrical side with no improvement before doing some actual trouble shooting. I gapped a spark plug to 1/4 inch and tried it on each cylinder. Number one had a nice spark and all others showed no spark. The engine only tries to start with #1 wire attached.

The points and condensor are new as is the coil, rotor and, cap. Plug wires look good. I pulled the rotor and cap and watched the points while cranking the engine. They don't appear to hit evenly on all four cylinders. It seems like this could be causing my lack of spark, but I'm not sure why the points whouldn't be striking evenly. Anyone seen this before or got a better explination for my lack of spark?

Thanks

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The spark plugs are supposed to be gapped at 0.025". 1/4 inch is 0.250". See the difference? The spark may not be able to jump THAT far.

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(quoted from post at 18:42:31 09/05/12) I am going to address the last portion of your post. If the distributor shaft is worn in the bushings where the shaft comes through, or is bent, or has some of the cam lobes worn down, it will run on only one cylinder, (or none, or all of them erratically).
With the rotor removed, Try to wiggle te shaft toward the engine and away from it, Up and down, and diagonally. If you detect any movement you can feel or see easily, it is time for a rebuilt distributor, or to have bushings put in yours. The tolerance is at or less than .001". Worn bushings allow radical timing changes and dwell changes than can prevent spark to some plugs.
I give it a 90% chance of being the issue. Setting the point gap at like .030 might get some more cylinders operating, but that is not going to fix it, just a possible check. Putting the distributor on a Sun Distributor machine will tell the story. If the bushing is bad no other help will be effective. Jim

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(quoted from post at 05:14:26 09/06/12) What do you mean by "hit evenly?"

Where did you read to set the plug gap to 1/4"? That's a new one on me, and I read a lot of these tractor fix forums.

A good spark should be able to jump 1/4". As long as you just use it as a test plug, and don't actually try to use it in the engine...

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(quoted from post at 07:00:31 09/06/12)

(quoted from post at 05:14:26 09/06/12) What do you mean by "hit evenly?"

Where did you read to set the plug gap to 1/4"? That's a new one on me, and I read a lot of these tractor fix forums.

A good spark should be able to jump 1/4". As long as you just use it as a test plug, and don't actually try to use it in the engine...

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mkirsch, check the last post on thes page

http://ytforums.ytmag.com/viewtopic.php?t=939239

and that's not the first place I've heard it. And, yeah, I was just using to test the spark, not putting it in the engine.

Thanks fr all the advice guys, hoping to get some time to work on the tractor today. The tail end of haying is keeping me busy.

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(quoted from post at 12:41:30 09/06/12) Not to be nit-picky, but that post says, "the spark will jump a 1/4" gap" or something like that...

It doesn't say anything about setting an actual spark plug to 1/4" and using that to test... All you need to do is pull each wire out of the distributor cap, roll back the rubber boot, and hold the metal contact 1/4" away from its post.

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