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

Hi everyone, great site and looking forward to spending some time round here.
Has anyone any idea how I dismantle the clutch on a SB Diplomat.
Looks like the drive has burned out and needs replaced and apparently no new parts are available and no shop will look at it so it needs to be a good old DIY job.
Any information of the best material to use, been told high density cork or to visit a motor cyle shop as they might have suitable material
Photos of the machine included below and thanks for any offer of help or advice as to how that comes apart

I have found this thread but have the same problem as the OP with it spinning in both directions, will try again tomorrow in daylight

https://www.outdoorking-forum.com.au/forum/ubbthreads.php?ubb=showflat&Number=18539#Post18539

You need to unscrew the center part with the two holes in it, by using the belt to keep the pulley part from rotating, and using a special spanner with two pins projecting to engage the two holes. Remember, though, that the center part is on a left hand thread. If you try to turn it the wrong way you'll just tighten it and make it difficult for yourself.

There is another thread referred to from the one you posted: follow that reference for some discussion on the special spanner and removing the central retaining nut:
https://www.outdoorking-forum.com.au/forum/u...Words=diplomat&Search=true#Post17291

Still getting nowhere with this, had a friend of a friend round whose a mechanic and he's stumped as well.
I'm sure I saw a while back you can order a new clutch plate from this website, if so I will order one, and in a few weeks when it arrives the mechanic is coming round with his angle grinder and welding gear and will grind the welds off that centre shaft, hopefully replace the clutch plate, and weld it back up again.
Will take pics and post back when it's being done to let everyone see.
In the meanwhile, any thoughts about grinding it off??, fraught with danger or a last resort??
I don't see any alternative myself.

PS Looks like the clutch plate for the Diplomat 430 is not available so it looks more than likely a kill or cure strategy for the old machine

Kempe, I can't say whether such strong measures are a good idea without really knowing how the whole drum mechanism works - but I doubt that is the best way to go forward, and I even doubt it would work. From the illustrated parts list it looks as if the clutch plate (the part with the two holes in it) screws onto the end of the drum shaft - the long shaft that goes all the way through both halves of the drum. If you can find a way to keep that shaft from rotating, it should be easy to unscrew the clutch plate from it. There might be a solution based on partly withdrawing the shaft so you can hold it. That is about as far as I can get without some better information. There are Outdoorking members who have done this job before - I hope one of them will step in here and tell us about it.

That's good advice Grumpy, as contained within the rear roller drum is a very fragile plastic ring gear....use care when removing the shaft.