Old 3.5hp Briggs question

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May 24, 2010
Piedmont, Ok
I have an old 3.5hp Briggs vert. shaft motor mounted on a frame for my train that I can ride in my yard. I is and has been very hard to start for a long long time. This is the second motor that I've had on it for this reason. I have pulled so hard and long on the starter rope that blisters have fromed between my fingers. The question that has come up is since this thing was on a mower and had a blade and now that I just have a pulley on it, do I need to change the flywheel from an old Horz. shaft motor? We tried to put a large block of steel on the shaft, but I only have 4' between the frames. All these old motors came off mowers that had run their course. Any thoughts to my problem?
Well, now I need to back up. Today I took the thing down to see why it would not start. No fire. Rust and crap on the flywheel and coil. Regapped the coil. Still no fire. Pulled the flywheel and you guessed it broke it. So now need another one anyway. This flywheel has teeth along the bottom for a vert. pull start rope, so not just any flywheel will work. We tried to weld it back. After checking the point gap and a not so straight flywheel, it did try to start before the wheel broke again. I'm going out tomorrow to try and find one around here...
Your starter is held on with two bolts on the side of the block and the bottom of the starter assy is about 4" diameter right?

You would begin your search for an old Toro Wirlwind 18" or 21" lawn mower. Most had Tecumseh engines but a few had a B&S with a Cast iron flywheel. Originally the blade on the Toro would be an S shape.
Plus if I am not mistaken that flywheel is easier removed using the screw on knocker on the shaft to prevent the breakage problems.

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