OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Question On Scott Bonnar Cylinder Mowers Different types of clutches.

Hello,

I have recently acquired a 33 and apart from the clutch always being engaged it was running quite well. After using it a few times I felt running it with the cylinder always spinning wasn't exactly the safest option.

Then it started. Engine off to replace the thrust pad. Clutch housing off because it was rattling. Now I have stripped it down to the frame and starting to look at all the parts for serviceability.

My first question is around the clutch. My clutch cone has taken a beating over the years it seems and the key has worn itself into the cone and the shaft. Am I able to take a 45 clutch and retrofit it to the 33 or would i be better off machining a new keyway into the shaft and cone and installing a new key? Keeping in mind there is about a 0.40mm clearance between the cone and shaft which should be a huge problem being a sliding part.

Second question regarding the clutch. I cant seem to make out a cork gasket or anything on the belt driven 33 drawings. Is this correct or should I be looking at installing a cork gasket like the 45 clutches?

Cheers for any new insights on my new project. I am sure there will be many more to come as I get into it.

Gary

G'day Gary
A warm welcome to these forums.

Modd BB or members should be able to offer suggestions here.
I'm not a mechanical whizz on this.

In the interim, I would like to make a couple of comments...
That must be doable. After all, it's what SB themselves did with the
first model Lawn King ... Type 'Model 33 Lawn King' in the Blue search bar above.

I think you're the first to point that error out here.
To my knowledge, there was no change in the use of a
conical cork lining on the main clutch of the belt/chain
and all chain drive Model 33s.

I hope this one is sorted.
The Model 33 is a fantastic, well-designed reel mower.

Cheers
------------------------
Jack

Hi Gary and Mod CJ,

Yes Jack is correct on both counts here. The Model 45 Clutch is directly interchangeable with the model 33 and to be honest it's a much better looking unit than what the 33 ever was. It's amazing what a few profile changes can do to the overall appearance of an item. The only thing that has to be done is to make up a spacer for the thrust pad end of the cone side as the 33 Clutch cone is longer in dimension than the 45 unit.

Once you line the two up side by side you'll immediately see what I'm referring to.

Cheers,
BB.

Cheers for the reply guys.

Im quite impressed with the 33 at the moment. For a 50/60 odd year old piece of kit.

I have read all sorts of comments about no parts available and such but the more I look into things, it appears there are some interchangeable items between the 33 and 45. I think the mechanical items, chains, bearings, belts, engine etc, shouldn't be a problem. Anything frame related might be an issue.

From what I can see. The thing I like about the 33 clutch is the taper lock onto the engine drive shaft. If the contact is there it is a very secure way of attachment.

I have done a little research into a new 45 clutch housing. Some decent dollars to be spent. Ie new housing, cone, shaft, bolts, lining. I'm pretty handy with the machines so I think I might attempt to machine a new keyway in the shaft and original cone before buying a whole new set up.

I will let you know how I go with the re-key.

Does anyone have any shaft and bore sizes by any chance? I have around 0.40mm clearance which doesn't seem too bad considering age and the fact its a sliding part.

Cheers,
Gary