The Tecumseh 9 HP was not as powerful as a Honda GX 270 which comes in about 8.5 HP. IF the friction wheel and drive plate can be made to transfer the power and not slip from 15 years of wear, this would be a wise choice. The problem is the 15 years will have taken their toll on the friction wheel, and the drive plate making that unlikely at best. The power is useless if it doesn't transfer to the wheels, that is what you need to concentrate on after 15 years.
90% of the horsepower is used to move the snow and only about10% or less to move the machine. If a human could push the machine into the snow that would be one person power. The only time the drive system will see a lot of stress is if the operator tries to go to fast into too much snow. If the operator uses the machine properly and matches the ground speed to the blowers ability to move the amount of snow in front of the blower the friction drive will see very little stress.
If the operator goes too fast into more snow then the blower section can handle then the blower becomes a snow plow and not a snow blower.
I put a GX340 on an old 80's Cub Cadet 8/26 that originally came with an 8hp tec flat head and it still has the original friction disk. If you try to hold it back on dry pavement it will pull you down the driveway or if you can get a good enough grip on it it will spin the tires on dry concrete but the friction disk does not slip.
I would not have any concerns putting a gx270 in place of an 9hp tech flat head.
Carl
