Pony Motor Question

It,s very possible it could be the mag. Also make sure it has spark plug wires with wire (not car wires) in them and are the spark plugs good? If it starts cold doesn,t seem like carb. troubles to me.

I ran into a problem like this on a D6. It turned out to be a short in the mag , that needed to be warm to happen. Check and see what kind of spark you have for warm versus cold. By the way it took me about 50 hours of trouble shooting to isolate. I changed plugs, wires, rebuilt the carb, checked compression hot and cold. I assumed that if I had a spark cold I would have one hot! After we replaced the mag it would start on the first or second pull every time, hot or cold.
Don

Pony starting problems related to hot and cold performance, are just about always 100% electrical origin. Weak electricals will break down when warm. Check your condensor to see if it's developing weakness whilst warm .. check for cracks in the cap that open up or that improve spark sidetracking when warm .. and check all insulated connections to see if warmth is making them break down. You are using the correct solid wire leads, I presume? .. and not carbon leads?

Like Oz said- condensor.

The spark plug wires could be the problem. I don't know how to tell the difference and they came with the machine. If its not the wires how do I determine if there is a short in mag? I know the cap is in good shape. Thank you all for your help.
Vinny

the other guys are proably rightwith the mag but one other thing comes to mind that if it is hot the rings will be loose check your compression cold before you start it then check it hot when it wont start .i had a pony motor that had more compression out of the air breather than ihad out of the exhust good luck😊 😊

Correct spark plug leads should have a wire core not carbon string. If your running Champion spark plugs get rid of them and change to NGK A6 (for 18mm). Check secondary winding of coil....should read approx. 6200 ohms.

Had the same problem with a 22 - one pull cold and away we went. As soon as she got hot, she'd die. Just like all the other posts here, it was a bad magneto.

I had the exact same symptom with a RD4 pony. The problem ended up being the coil in the mag. Pony would spark when cold, no spark when warm. Easy to diagnose. When the pony is cold you will see spark at the plug wires. It won't be a great spark, but enough to start. After it is warm, pull a plug wire and position it close to the plug. Now pull the rope and see that the spark is gone. No spark is either coil, maybe condenser. Probably the coil because I think a bad condenser is bad all the time. This problem with the coil was several years ago and I remember this because the coil cost me $80. I now see a website magnetoparts.com and the prices there look ok.