Sorry. I've done so much that I left a few things out. I've checked the cap, even removing it while it's running with no effect. Tried the carb spray and even took the hood off so I can get everywhere. Checked the flywheel key to make sure by some fluke it wasn't cracked. Eliminated the fuel filter temporarily to eliminated that.Adding choke runs worse, but if I throttle it back a little its not as bad. Ive been over the wiring and checked every connector I can find, nothing burnt or corroded.

Compare valve lift?

Thought I was doing pretty good until now. You just went over my head

My thought process was if the choke makes it worse and throttle down makes it better, then maybe the thing isn't breathing as well as it should. These camshaft lobes can wear so a valve may not be fully opening. Someone that works on these more frequently can tell by how they run that they sound anemic. A surge could be reach, but if you have accurately covered the steps you have done so far- it would be good to check. Afterall, our terminology could be somewhat different. Remove the valve cover and crank the engine and see if each valve opens about the same or does one have much less travel. Now you have just compared the lift.

I'll give it a shot tomorrow evening and post my results

OK. removed plug and valve cover. As near as I can tell by eyeballing there is no difference in the amount the valve opens.

I don't suppose that you blew back through the fuel line into the tank to ensure that there wasn't debris in it or that there isn't a bug or other debris that can float over the outlet in the bottom of the tank? Also, ideally keep the routing of the fuel line no lower than the bowl.

Yeah, did that in the beginning. Everything is clear. The fuel line though has got me thinking. It swoops down from the factory probably an inch below the bowl. I'll try straightening that out and see what happens.

Tried rerouting the fuel line wuth no change. I was pretty tired when I looked at the valves so I decided to take a second look. I missed it...Looks like the bottom valve is opening quite a bit more than the top. Worn cam?

Yes. Your exhaust is exhausted. New cam time.

Thanks. At least now I have the cause. Now on to the cure....

I can send you a Service Manual for your engine IF you like. Address below, put i n proper format and remind me engine model number and what you want.

Walt Conner

wconner5 at frontier dot com

I would really appreciate that. I'll send you an email tonight

New cam is in, just finished mowing the section of the yard that reached almost a foot tall. Runs like a new machine. Just wanted to thank everyone that helped. Couldn't have done it without you.

Use some top end lube occasionally on that Intek may solve some of that Cam Wear in the future Bro !