OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Question On Scott Bonnar Cylinder Mowers Scott Bonnar 45 clutch slipping under load

Hi to dramapig, and BB,
And my thanks for posting the pics, and for BB's observations, regarding the thrust-pad.

They say pictures say a thousand words...and there is no exception in this case....The problem is with the clutch cork that is glued to the inside of the outer clutch-half...or should I say lack of it!

I believe that would explain all your symptoms, as the cork has most probably worn well past its used-by-date.

I have come to this conclusion because of the excessive protrusion of the inner clutch cone when it is engaged, and not depressed far enough when it is dis-engaged.

Here's your pic of the excessive protrusion:

Clutch engaged....

Here's mine....
Clutch engaged....

Here's your pic of the clutch cone not depressed far enough to dis-engage:

Clutch disengaged

And here's mine...
Clutch dis-engaged....

You will need to follow my "Engine and Clutch Removal Guide" HERE and remove the cutter clutch assembly and examine the clutch cork....and replace it. You will have to remove all of the old cork carefully and all traces of the old glue...Eucalyptus oil may help with the glue removal, then you have to remove all trace of the oil....'Prepsol' (wax and grease remover) is excellent for that!

The replacement cork can be found HERE

This is the method of gluing the new cork in place and the recommended glue for the purpose...


Here is a pic of a used cork in place, with heaps of life left in it....for comparison with yours, after removal....

Good luck, and please keep the pics coming....