When I got her it was a trade for work and it wasn;t running good and smoked a lot.
I bought the book the parts and put new rings and gaskets on the motor.. put her back together and relized I needed a timing chain also. So I went back into her and repalced the timing chain, then took it to the shop because I suck at adjusting the valves. She ran like a top.
I rolled her over and I started her back up, finished the day and parked it. About 2 weeks later I went to start it and it wouldn't run. I pulled the carb off and blew it out with compressed air before I saw the book said don't use compressed air with the diaphram still in the carb.. Well I think it got streched.. I noticed when I checked the oil it was full of gas.
The mechanic said the float was stuck and the petcock is bad. So he put an inline fuel shut off valve adjusted the valves and he got her running.but it would only run with the choke on and when I pressed the gas hard it died.
He said it was a timing problem.. It's not. I pulled it all back to peices. She has spark,compression, cylinder is fine piston is fine, and timing is on both the marks. I also replaced the broken choke/starter cable holder that screws into the carb. Still no luck..
I am sure the valves are still out a little but my guess is a strech diaphram. Am I close?

 

i would replace the diaphram, if its messed up it can leak gas into the engine, and would explain your idol problem.

 

I thought that. I know the last time I opened it up I had to tuck the diaphram into the housing to make it fit and work the cap around it.

 

usually it just fits right in no problem. you should also try cleaning you pilot jet, most of the time if you have an idol problem it is a dirty or clogged pilot.

the pilot is located outside the bowl twords the engine. note how many turns OUT it is before you remove it. clean then reinstall to that many turns out.