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dcatoffm

Simplicity Model M... Flywheel Nut

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dcatoffm
Have a Simplicity Model M hand tractor powered by a Briggs and Stratton model 9 engine. It has low compression and no spark. I need to get the flywheel off to get at the magneto. It's secured with a 1 1/4" nut in the crank shaft that doesn't want to move either direction. You'd think this information would be readily available but apparently not as I have wasted the whole day trying to find out, and have gotten conflicting information from different dealers. The question: Is this nut a standard or a reverse thread? I'd like to find out before I break something, myself included. Thank you.

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briggsetc
Make sure to try a condensor first. That will be a standard right hand thread. After you get the lock plate off. Get a piece of aluminum or brass and whack the shaft end hard and straight once to remove. What you have is the famous Magnamatic ignition that has an extreemly high ciol failure rate. Usually they start and run then quit when hot. Most people chase carb and other problems at that point. If the coil is even still available, P/N 290880, it is over 125.00. However someone, I think Kent Redd, developed a nice fix using a common later briggs coil. The conversion was in the Nov 2005 issue of Gas Engine Magazine. They have a site. You can search smokstak.com and maybe find the coil info. You will most likley find that Model 9 in good shape if someone didn't abuse it. They were an extreemly well built unit. Gary

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HubbardRA
Every B/S that I have worked on was right hand thread, "except one". I broke the end off the crankshaft trying to remove the nut from that one. It was on a walk behind reel mower that started with a lever instead of a rope pull. It was fixed by drilling the center of the crankshaft and tapping. A bolt was then screwed in to hold the flywheel on.

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dcatoffm
Thank you Gary. I found the referenced article and a few more reference items too. I probably won't get back to work on this project until some time after the holiday weekend, but I just wanted to let you know I did find your reply useful. Thank you again. :) @ Rod, I read that the 5S was a reverse thread, may it have been that early an engine? Anyway, I'll keep that in mind. Thank you too.

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HubbardRA
Don't know the engine designation. It was a very old mower. The only one I ever saw that used a ratcheting lever arm to start it. You grabbed the lever (handle) and pushed it toward the mower and it would spin the motor over then disengage. After I broke the end off the crank, I traded it to a friend who fixed it then traded it off. At the time it had been given to me by another friend and I was just fixing it up more as a toy than to mow my lawn. After breaking the crank I was so frustrated that I just got rid of it. Now I wish I had kept it.

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dcatoffm
Not to be a pain, but does anybody have a visual guide to K. Redd's cheap fix? Detailed drawings or photos (or even video)? I'm reading the model 9 manual and I'm having a hard time "seeing" how this works, and visual is just the kind of person I am. I get the concept, it's more about the physical fit and how (if) it interacts with the stock rotor. Thanks.

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