Running rich when NOT under load

Only coils for use on a points ignition can be reliably tested with an Ohm meter due to the chip.
A lot of shaved monkeys why learned how to work a video camera put all sorts of junk on the web.
The kit you need to test an ignition module is a bit north of a grand down here so an inline tester on a coil with the kill wire disconnected will do for me.
No one has ever complained and every time I have replaced a coil the engine has worked well after .

Okay, thanks Bert, I'm going to pick one up this week

I suppose it might be time to throw in the towel. I went to TriGreen and picked up a new coil to the tune of $117. Put in on, set the gap and started it up. No change, if anything the surging is worse and more frequent. Instead of running smooth for 2 or 3 seconds and then sputtering for a second with a puff of black smoke, now it is a constant surging that seemed to get much worse as I had it running for about 10 minutes. Finally it got so bad that it bogged down and died. Thinking it must now either be the carb or the valves I removed the carb and went through it one more time just in case I missed something. No change. I removed the valve cover and checked the gap. For the second time I had set the gap at TDC on the compression stroke at .006 for the intake and exhaust. For the second time when I checked they had loosened. The intake was .14 and the exhaust was .11. The push rods were good and straight. I loosened the locking nut and adjusted the set screws to set the gap again at .006. I held the set screw in place while tightening the locking nut. It was too late to crank it to see if that made any difference but I'm not hopeful. At this point I have no idea what could be causing the surging. I have replaced the spark plug twice (in case one was bad), new fuel pump, fuel filter, fuel lines, air filter and pre-cleaner, new battery and the carb has been cleaned about a dozen times. I have fresh oil, oil filter and fresh gas. I'm at a loss and guessing it might be time to take it in and have a professional check it out. That's the last thing I want to do but I'm out of ideas. Don't know why the valve lash is not staying set.

So what happened with the spark tester ?
last we heard from you you were going to get one and check for a constant spark.

If the valve lash seems to changing all the time that is a sign of a loose guide which is new head time

arch252 said:

I was able to pick up a key today. I went ahead and pulled the head and checked for sticking valves. The valves looked great, closed tightly, would not let any fluid pass when seated. I rechecked the valve lash and it was good. I replaced the spark plug again with another new one just in case I had a bad plug. Buttoned it all up and it started right away and ran smooth as silk for about a minute. As soon as it warmed up it started the same thing as before, sputtering at high idle with no load. Every few seconds it would sputter and spit out some black smoke. When the PTO was engaged it smoothed out. The sputter was still there but barely noticeable. I checked the spark with the inline tester. The spark was intermittent when it would sputter. Barely noticeable but not a smooth consistent spark. So...was the spark intermittent because of the sputter or did the intermittent spark cause the sputter? I made a short video where you can hear the engine surge/sputter and see the inline tester. I don't know of any way to upload a video though.

I've about ruled out the float, if it were the float it seems like the problem would have been consistent from the initial start, not a minute later after the engine is warm.

I'm really leaning toward the ignition coil at this point. Am I on the right track? Anything else I should check before I mortgage my house for a new coil?

Click to expand...

I had already checked it with an inline tester a couple of weeks ago.

Sorry. I must have missed that.
I check ignitions by disconnecting the cut out wire and watching.
The magneto sparks each revolution so will always appear solid even when you have a miss caused by the carb.

I have not messed with the governor linkage. It is possible that could have anything to do with this?