OutdoorKing Repair Forum Forums Collectors Corner Cylinder Scott Bonnar 33 clutch lining?

I am restoring a 33 - I have the original clutch but the assembly has me perplexed. I sourced a 45 clutch lining (thinking that they would be the same?) but the thickness of the lining does not allow the cone to bed down. The cone is only about a third into the corresponding section before it binds and the back section will not come together because of the incorrect fit.
Any advice?

Toby.

Hello Malcolm Arnold
I'm not sure what's going on here.

The 33 parts list suggests the lining should be interchangeable
with the 45.

I have seen very poor reproduction clutch linings.
[one I saw was straight cut!].

I'm hoping some member with experience on the 33 and 45
will help here ...

------------------------------
Jack.

As Jack has already suggested, the lining is the exact same part shared between the models.

Which model of 33? The clutches vary between versions.

Yes the later 33's had the Model 45 clutch fitted as they were built side by side with the 33 being sold as the Lawnking until it was dropped and the Lawnking was a 45 as well.

The 330413 doesn't actually show an engine clutch lining. The 330026 shows a 45 style cotter pin clutch with lining (guess this is the same as a 33001 lawn king?).

There doesn't seem to be any literature on a Bonmow/ Villiers type 33, but I've got an early flat handle bar/ wooden roller 33 so I'm curious.

Hello Asteroid and BB
I hope we can get to the bottom of this.



The parts list I have for a 33041 does not appear
to show a primary clutch lining.

---------------------------
Jack

Hi, Asteroid.

I have (2) two 33` s (parts there of).

(a) 33 919 - flat bar handles (which I am restoring)

(b) 33 10569 - chrome round section handles which can be halved in length for transportation.

I have (2) two inner cones - which are the same and one outer cone with it`s rear mating surface. So the clutch is a mix mash of
parts. Unlike the 45 clutch there is no grub screw to the shaft - mine has the collar and lock nut.

I have a Scott Bonner Operating and Maintenance Instructions booklet Model 33 16inch 330026.

I have (2) two engines - Villers Midget 98cc 1953 * and a Kirby Tecumseh.

* this engine came off a Model 19 Scott Bonner which was very rusty - I have some parts that I saved from this mower.

So the early 33 clutches did not have a cork lining like the 45`s - Just metal to metal cone surfaces?

Hi, Jack.

Thank you for the diagram showing the 33041 model.

My 33 919 plated solid deck is different to the one shown in the 33041 diagram (my 33 10568 mower) in that the engine clutch fork mechanism does not sit on a raised block # 138, nor does it have the "bracing bracket" # 150. The engine bolt holes (4 of) in the solid decks are drilled in a different position to reflect the different engines used and the clutch mechanism holes (3 of) are drilled in a different position (to allow the use of the bracing bar on the 33041?)

Hello Malcolm Arnold,
Many thanks for your observations.

It shows just how much we do not know here.

It makes no engineering sense - to me - that this cone
clutch worked without some clutch lining.

Malcolm, any thoughts?

I hope a member will come forward and explain this.

cheers and thanks
---------------------------------
Jack

Hi Jack and Malcolm


Yes as we know the cone clutch is one of the cheapest clutches to produce so why not make it
cheaper again and have metal to metal contact.

The Qualcast Royal Blade from memory has no lining on the cone clutch just metal to metal contact ,I've
looked at a Qualcast Royal Blade cone clutch before but haven't seen the SB 33 apart from this Forum.

I can think of a few examples where this type of cone clutch does not have a replaceable clutch lining eg.synchro rings used
for automotive gearboxes ,LSD differentials used in many vehicles but these two examples are in a wet environment.

The cone LS Differentials are metal to metal contact.



Cheers
Max

Hi Max
Many, many thanks.

I have limited knowledge here, and have no parts list for
the Royal Blade.

These mower cone clutches work in such a hostile environment -
not sealed, nor wet.

I hope this one will be solved.

Was this a bold SB experiment?

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

G'day Jack

The old push bikes that you pedaled backwards to operate the rear brake had a type of cone clutch and from
what I remember there was no clutch lining on the cones just metal to metal contact and bikes were in
hostile environments.

Outboard motors use a cone clutch without a clutch lining.

I will see if I can get some images of the Royal Blade cone clutch.


Cheers
Max.

Evening, Max.

Thank you for expanding our understanding of the operation of a metal to metal clutch. Neither surfaces of the inner and outer cones of my SB 33 clutch exhibit any signs of scoring / wear. I will have to wait till I have the mower assembled (awaiting a part for the rear roller) before I put it to the test.

Malcolm.

G'day Malcolm and Jack

No problem Malcolm and Jack ,another item I saw that you probably wouldn't think of having
a cone clutch was a 1880 stop watch, I've finally got some images of the Royal Blade cone clutch .


Cheers
Max

This relates to the discussion of the Type 33 SB. I have one like this with the dry cone (cast iron) clutch and it works ok and is quite common for light duties (low power transmission).

Can I take this opportunity to ask a few questions (I am new to this Forum) ? Directed to Jack mainly.
1.- When you refer to "Model 330026" the "0026" is not the number on the name plate, Is it? (My mover has a "33 2887" number on the plate.
2.- My mower has tubular, one piece handlebars (like 330026 exploded drawing) but has a Belt Drive (like 330413) and a grommet on the chain cover.
3.- Any chance of getting a better resolution pdfs of the exploded views and spare parts listing.

Regards
Voytek

G'day Max, Voytek S and all cone clutch lovers
I wished I had never said that that clutch lacked engineering sense.
I should have said it made no sense in Scott Bonnar history.

I have since learned that Scott Bonnar did use a friction cone clutch
for reel protection on their post WWII Model 19.


https://www.outdoorking-forum.com.au/forum/ubbthreads.php/topics/65009/model-19-history-record-c1953.html

That's right, Scott Bonnar were not consistent here.
What you have is a mower serial number.

I'll see what I can find with better resolution pdfs.
Give me a bit of time.

Max, sincere thanks for the Royal Blade images. Brilliant.

The obvious question is why did SB abandon the 33 clutch
when it introduced the Model 45?

Maybe the answers goes to the properties of cast iron
versus aluminium. Any ideas?

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

Hi Jack and Voytek S


I was thinking it would depend on engine choice used on a particular reel mower as to what cone clutch is used
for instance if the engine choice was a Tecumseh horizontal shaft with an alloy flywheel you would need a cast
iron cone clutch to act as a rotating mass (flywheel) but if the Briggs and Stratton horizontal shaft motor with the
cast iron flywheel is used then the alloy clutch was fitted.

Heavy Flywheel = Light Clutch and Light Flywheel = Heavy Clutch

That's what i was thinking from a design perspective .



Cheers
Max.

Makes sense.

Jack
Do you have access to SB production data? I would love to know what year my mower was made. (2887).
I am restoring my beloved one, less new engine (I'm putting in some bloody Chinese thing, but matching the Briggs and Stratton 2.5 HP original one). Will post some pics soon, when she is up and doing her job.
Cheers