Have a look at the FYI post on the tractor forum. You may have a similar problem.

Are you saying it has become physically harder to pull the starter cord? It must have a compression release that is stuck. Put some Marvel Mystery Oil in the oil and gas - 2 ounces each.

Yes. Physically harder to pull. The ESP is a Tecumseh patented technology that affords easy pull easy starting. But that doesn't work anymore. I have gotten advice ranging from a possible sheared flywheel key to the valve clearances need to be reset. Can't find anything specific about how to troubleshoot this ESP even though it has been out since 2000. I don't really have the specialty tools to be pulling the flywheel off. Does the Mystery Oil still sound appropriate?

Well, it won't hurt anything and will give the engine an inside-out cleaning. It has to have a compression release to be 'easy start'. However, the other suggestions sound mostly valid to me. Have you hit anything with the blade that stopped the engine? Even if the flywheel were slightly turned, throwing off the spark, a working compression release would still make it easy to pull through.

I have the same mower, but with both electric start and recoil. Yes, your valve clearance may be out of adjustment with too much clearance. This prevents the ESP from working. By the way, the ESP is mechanical compression release (MCR) which delays the closing of the intake valve and reduces the compression during start-up. MCR is the technical name and ESP is the marketing name. To check if it is MCR related problem remove the spark plug and see if the engine spins freely. You can also determine this without removing the plug and noting if the engine only becomes difficult to pull on the compression stroke and spins freely on the others. If so, you need to check the valve clearance. Although you will need intermediate engine mechanic skills to do the valve adj, you can find a free online TEC service manual on the web for the valve adjustment procedure. If the valve clearance is OK, then the MCR could be the problem which might require a camshaft replacement.

I just finished working on a friend's Scott's mower (Tecumseh engine OVRM120-22032D) which had the same symptoms.

As the other members have suggested, it had a slightly bent flywheel key and the valve lash on both valves was about 4X greater than the spec called for (.016" versus .004"). I also replaced the recoil starter which was damaged, but yours may be okay.

If you find the valves need to be adjusted (to help the MCR do its job), a 7/16 crowfoot wrench makes getting at the intake valve locknut easier (on his machine), but I just raised the engine off the deck some to get enough clearance.

Jim

my father has this mower and he is trying to find out where the pressure relief valve is located. also any info on where to get a manual for model #229630x8a any info would be great thanks