My blower starts faithfully when the engine is cold. If I used it for any length of time and shut it off, then I need to let it sit for at least an hour before I can get it to start again. Any suggestions, is my carb adjusted too rich??

So my old '77 Gehl skidloader has intermittent ignition problems. 2 cylinder engine. It has new points and condenser that probably only have 3-4 hours on them. Correctly gapped, timing is preset. (Ignition plunger rides directly on the cam) Points don't always seem to be making contact when they close. Once it's running it runs fine... never misfires or quits. But every once in a while when you go to start it again, it won't fire... and once the cover is removed I find no spark across the points. (Especially easy to see at night) I dont think they are oily. To get it started again all I have to do is crank it over while jumping the points with a small flat screwdriver, it fires and will start. Any ideas of what I should check? Some sort of intermittent ground maybe? Could the ignition plunger be worn down, throwing off the timing and dwell?