I came across this thread by searching for the same answer a lot of others on here are seeking. After reading the entire page, I had to join to point out an observation in regards to rusyj14's comment that "Occasionally, the help doesn't work, mainly because the help seekers can't follow instructions" But, the fact is, the seekers Are following instructions. No disrespect meant, as I see many have resolved their problem with your help. But the others that are still at square one have done as instructed. They have repeatedly stated those instructions back, as to what they had done, but with no fix. And as you also mentioned for them to do, they Are here asking for help, but it seems their posts are going unanswered. From someone who at the age of 10, or younger, got his hands on his first lawn mower with instructions from his Dad to only tear it apart to see what was inside, with a Tecumseh that had sat out in the weather since who knows when, with a crankcase full of rain water, but defied his Dad and got it running to have it mow his grass for the next six or more years, I've been accustomed to getting things running. But having already done what all others on here have suggested before finding this thread, I am leaning towards the flywheel magnets having somehow lost their strength. It is the only part not bought new to replace. I thought I had read somewhere else that someone was able to compare the strength between a good set of magnets and weak ones by use of a fish scale and how much it took to pull away from it, but I couldn't find it again. I'll be completely dumbfounded if a new correct flywheel does not solve my issue either, as I've mentioned, it is the only part I have not yet bought to have everything brand new with regards to the ignition system. If I had a shop nearby that could magnetize it, I would go that route, but it will be cheaper to purchase a new one than to invest in the shipping and shop time to have it done.

Hi Bill. I know the deal about cleaning the main jet orifices. The "seal" I have mentioned is the intake valve seal. The exhaust valve did NOT have one. This is one of those non-adjustable WOT carbs, known not to have an actual idle circuit. I removed and cleaned the head and all head parts, but I didn't lap the valves. They may NOT be seating 100%, but the carb was soaked and cleaned with no parts replaced except maybe the bowl gasket. I realize the brass bowl bolt is the main jet. I will try a couple different things, recheck the valve lash, run some MMO thru it and see.

Bought used riding mower w/ engine trouble. 21 hp intek plus b&s (could not determine model etc on engine, shroud, inside of hood). Craftsman 2000 42". Will crank in choke but only for 10-15 secs. Will not run out of choke. Tried everything me and 3 neighbors could think of. Today I did comp test w/ only 30psi....should be around 120 on 3 yr old engine. What should I do to fix the compression problem?

Thanks for all the feedback. I did contact the Tulsa Engine folks for advice and Matt said the 331877 could be a direct replacement for my current (dead) 311777. I looked at the IPL's for both engines (311700 vs. 331800) and some PN's are the same, others are different. The main parts (sump, head, crank, flywheel, rod, piston, cam, valves) are all different which makes me nervous. Others (starter, magneto, fuel pump, alternator, regulator, wiring harness) are the same so maybe it is okay. Regardless, I think I'll still call Tulsa and talk via phone vs. just email so I can get more feedback. Again, at the end of the day, if the crankshaft size is the same and the bolt pattern is the same, I want to take advantage of the bigger HP unit if possible. I want to make sure too that I get the right engine. Any more advice to share is appreciated. Again, thanks for taking your time to help me out.