OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Question On Scott Bonnar Cylinder Mowers Help

Hey guys

just picked up my first scott bonnar 20" cylinder mower.

I mowed my front yard fine and half my back yard then it just died. Got it going again. Went to engage the blades and noticed they were already spinning slighty. It started making some weird clunking noises as the blade spun then stopped. And when i engaged the blades the throttle had no control it was just full power no matter how much i moved the adjuster. Any one know what it could be?

i just got it started again, with the blade clutch disengaged the blades were still spinning. Sometimes when it starts the blades aren't spinning but after a second or two the blades engage and start spinning.

Hi 8lueoval,

Being a 20 inch machine I have to ask is it a twin railer or a solid deck mower ?

Cheers,
BB

im unsure this is it though

It's a twin railer as the engine sits on two rails.

Well it looks rather nice and I'm wondering if there are any fractures to the rails around the engine mount holes that have been hidden by fresh paint. If not then I would say that the engine is not properly aligned with the transfer shaft thus off centering the clutch from the clutch cone and creating a grab / let go / grab situation.

Cheers,
BB

Thanks for the reply, after reading your posts i ran my hand under the rail and i could feel a weld the whole way along. The engine also wasn't flush. I asked for my money back which the guy gave me, so it turned out alright. I have now purchased a single deck one with 12 blade reel in just as good condition for a little bit more coin.

Hi 8lueoval,

All I can say is you are rather lucky that you got your cash back, many would just say Caveat Emptor, which means buyer beware.

Cheers,
BB

He was a very nice older bloke. And he couldn't figure out what was wrong. He does it as a small "business" so i guess he kinda has to live up to his name.

Honestly he sounds like a bit of an amateur that got caught in his own web.

He knew exactly what he was up to but he's messed it up and been caught out. 20 inch machines are much harder to solve rail issues as they have more latitude for alignment error due to the longer rails.

The twin rail 20 inch 45's were never successful and as such were deleted rather quickly. If you are going to buy a 20 inch machine you should always buy an earlier unit that has the solid deck, you can't go wrong.

Cheers,
BB

Yeap and thats what i thought. Ive just bought a single deck 20in. Can't wait to get it, getting the blades sharpened atm. This is my front lawn. Last pic was cut with the dogey 20in

Pics taken every monday for 5 weeks

That's nice transformation, have you been watering or just all the rain that we have had ? Good luck with your new mower !

first pic was the day it got cored. Laid some blood and bones fert on top of that. I haven't watered it at all. Then about the 3rd week a bag of ck88