Tecumseh 10hp misfire at idle everything‘s been done

So I brought a used Coleman generator with a Tecumseh 10hp engine. So at idle it misfires. When there is a load on the generator it stops misfiring but when there is no load on its misfiring. so I replaced the spark plug and replaced carburetor. Still no good. Removed flywheel to check the key. No problem was found there. Adjusted valve clearance .010 on both valves had to grind the exhaust valve quite a bit to get it to fall in spec. Still no good. I removed the head again and found valve Guide loose on exhaust valve so I replaced the hole block with one from eBay. It’s brand new with valves in it still missing but it’s not popping out the exhaust like before but still missing bad. So I swapped the cam with decompression mechanism on it with one out of a good running snowblower and the lifters also. Still the same thing. I also swapped out coil spark plug and carburetor still the same. I did reuse the rings in a new cylinder going to do leak down test tonight and check valve adjustment again. Any help would be greatly appreciated.