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

Hi Guys,

Just a quick one, did the "Supercut" ever come out with a petrol engine on a 20 Inch or only as an electric unit ?

I know the 14 and 16 inch units were released with a Villiers engine but I'm not sure about the 20 Inch unit which I managed to pick up an original unit for absolutely nothing. Boy is it a heavy beast and not one for the average home, especially with that in or out clutch arrangement, give me a solid deck model 45 anytime.

Look forward to any answers

Cheers,
Bonnar_Bloke

Hi bonnar_bloke,

The Scott Bonnar Model 17 "Supercut petrol mowers were first introduced in 1950 and came in 14", 16", 18", 20" and a little later the 24" cutting widths.
Here's an advert...

on scoring a petrol 18" machine.

Hi Darryl,

Firstly thanks for that. Its a great ad and thanks for putting that up.

Now my next dilemma is that my 20 inch unit is electric and I've scored a 17 inch Supercut that has the Villiers engine on it and is basically a scrapper. I'm wondering how much would be involved and if it is actually possible to change the 20 inch to petrol as I haven't got the 17 inch unit in my possession as yet, that's happening on Thursday. Personally I think that it's drawing a long bow due to the two differing power plant set ups.
Anyway I'd love to hear your view. Honestly the electric will run instantly regardless of how long you put it in storage for where as petrol units always require so much maintenance if left unattended for too long. I have a multitude of model 45's in various stages of restoration but all of them have been put on hold until I move into my new abode complete with a massive size workshop, something I've been deprived of for a few years now while still collecting the odd Scott Bonnar.

Cheers,
BB.

Hi again BB,

The task of converting a Supercut Model 17 Electric to a petrol model is not all that difficult, if both are the same size (cutting widths) machines because the Model 17 uses a counter shaft (that's the one in front of the engine) that contains the cutter clutch assembly.... and, the double pulley or chain sprocket that drives the machine.

If that is the case, it is just a matter of transferring all from one to the other, with all the ancillary
gear that goes with it (levers, clutch release brackets etc....and then set it up correctly.

And, to be blunt, who wants to use a Villiers engine...that was reliable in its day, but now can be pernickety...even if well maintained...I know this, because I have done this before and the engine was its failing...I should have followed my dream and replaced it with a Honda.
But my hopes were dashed, back in 1987, when the machine was stolen...So I will never know the outcome of the conversion.

Today, I have a Model 17 Supercut Electric, 18" cut, that is in good mechanical condition....but part of me would like to do a conversion to petrol....but I need the parts..and at the prices they are commanding, I think it might be a pipe dream!
I hope this has been of help.
All good stuff,

Hi Darryl,

I'm not sure but I think you've got the wrong end of the stick, its the 20 inch Electric unit that I would like to convert to petrol and I am getting a 18 inch petrol powered unit given to me on Thursday. I'm happy to sacrifice the 18 inch unit to get the 20 inch up to a good petrol powered unit opposed to it being electric.

Sorry if I've confused you, but regardless of that I'm thinking of I feel shaft lengths are going to be an issue as a 18 (Petrol) would have shorter units than a 20 inch (Electric). If it was the other way round it would be easier as shafts can always be shortened but lengthening them would not be that feasible.

Yes the Villiers is definitely not my weapon of choice, a good Chonda would work well with a 20 inch unit. Also sorry that I've called the smaller unit a 17inch in the previous post as I got it confused with it being a Model 17 that was only released in 14, 18, 20 and 24 inches.

Let me know what you're thinking Darryl.

Cheers,
BB

Hi BB,

Without photo's of the counter shafts in question in front of me, its hard to give you good advice...if the shafts were the same size, its an easy swap over, but as their not, I don't know how the cutter clutch set up relates to the counter shaft and if that set up can be fitted to the 20" shaft.

I think that the pulley/sprocket can slide along and is locked to the shaft by grub screws....but the cutter clutch...I just can't remember.

Hi Darryl,

I'll just wait until I get the 18 inch unit on Thursday and then take shots of both machines and put them up so we can all judge what needs to be done.

Cheers,
BB

Some photos would be a help. I'm wondering if the problem could be solved just by making a simple dummy side-plate that sits 2" in from the real one. Then the engine could be mounted in the right relationship to the dummy side-plate. The whole setup of shafts, clutch etc from the 18" could be transferred unmodified.

Hi grumpy,

The set up of a Scott Bonnar Model 17 (Circa 1950) is not that simple, we are talking about the counter-shaft...which has bearings at each end, (and before you ask, I don't know if they are self aligning, Lol) and it has a pulley, (sometimes a double, with 'V'belts) or a chain driven sprocket (Usually large, up to 91 teeth) and has the cutter clutch attached...(that method is what I can't remember) but is not a set up that can't use dummy side plates, (when you see the machine, in the flesh you will understand why) unfortunately...

This counter shaft is attached to bevel gearing, which powers the cylinder reel, and final drive for the rear roller.

I can supply pics if necessary...
All good stuff,

I think some pics would help, Deejay. I've been visualising the outputs being on the left side of the mower, when facing forward. The dummy side plate would be on the right side, which I thought only supported bearings for a shaft or two. However I'm not at all familiar with the machine.

Hi grumpy, unfortunately my Supercut is buried under cover in a corner of the shed, I would have to pull everything out to get to it, to take pics and it is an electric, and does not have a cutter clutch.

We need pics of the petrol version's counter shaft, which hopefully BB will post after its arrival tomorrow.

Well Guys I've got both machines now and I very much feel that it would be a waste of time doing the conversion as Darryl said the Electric does not have a cutter clutch and has the cutter running the moment the power switch is activated. The only thing you do with an electric is engage the drive in or out and to be brutally honest it is a bit of crude set up compared to the Model 45 which has far more controllable drive as you can slip the clutch with your hand when you don't require full drive power where as the Supercuts are basically drive forward full steam ahead when engaged.

Anyway here are some photos of both machines which to be truthful are best restored in their own identity rather than butchering two machines to gain one halfcast. Anyway that's my opinion.








The ID plate that actually says Model 17 on it is the Petrol unit with the Villiers while the one denoted as SC is the Electric.

I'm still pondering whether to get the Villiers engine going as it currently has a very internally rusty Kirby Lawson tank attached to it and I won't risk running rusty fuel through it, why it has the tank substituted I don't know, but obviously something happened to the original barrel tank.

The Petrol unit has a great cutter and a superb bedknife on it so I'm very much feeling that I would love to restore the Villiers powered unit to its former glory, while the electric is a far better tennis court / private lawn bowls mower due to it having less vibration than a petrol unit. Also both catchers are in pretty good nick.

Just added a few more close up shots, one of the Villiers Air Cleaner that is closable, but I can't seem to work out where it ever fitted on the engine. Maybe I'm just too smitten with these two machines that I can't see the forest for the trees.

Regardless, these babies were built bullet and bomb proof as these will never suffer from cracked rails or top decks like the feeble 45's that's only when comparing them to the Supercuts build and strength level, that's for sure.

Will be interested in the feedback from Grumpy, Deejay and anyone else that wishes to comment.

BTW, complete investment was $20 and a nice drive out in the country.

I agree you would be butchering two machines to produce one mongrel and one pile of scrap. It is the sort of thing that is only done by somebody desperate for a cheap reel mower, not by a person who has any kind feelings toward Scott Bonnar classics. I think it would not be very difficult, but the scrap-to-useful-output ratio would be awful.

Unfortunately the same line of thinking (emphasis on preserving our mower heritage) says you have to keep the Villiers engine and tidy up the smaller mower to make it usable. Whether you tidy up the electric machine as well, or just store it safely for the next generation, is a secondary question.

I'm no expert but the fuel tank and the carby are the wrong ones for the villiers engine I think?

The air filter should go directly onto the body of the carby facing toward the catcher.

The tank should be cylindrical with a tin cap.

Hi BB, and Agro mick,

I agree with Agro that the carby (and obviously the fuel tank) is not original for that engine,and that the air cleaner you have is attached to the carby facing forward.
See the pic here...

This is not your mark of engine, but you will get the idea.

BB, I will send you a PM regarding spare parts for your engine.
By the way, did you get the crank handle with the petrol Super Cut? It engages with a 'dog' in the front counter shaft bearing holder.
Here's a pic regarding the colour scheme...


It is correct except for the colour in the chain-case for the SB name etc, which as you see on yours was red.

Hi Grumpy, Agro M and Deejay,

I totally agree with Grumpy's comments regarding the basic destruction of two machines and not for one moment would I even consider doing that if both machines weren't salvageable. When I originally made the enquiry regarding the conversion of an electric unit to a petrol unit I had only seen very poor photos of the petrol unit and felt that it may have been too far gone but the photos I've posted up of the petrol 18 inch unit are after I cleaned it and oiled many components as it has sat for 15 years outside in the Adelaide Hills at a property under a lean to roof attached on the side of a barn at Stirling, a stone throw away from the South Eastern Freeway.

My intention is to totally refurbish the Villiers powered mower to what is shown in the original ad that Deejay put up on this thread and probably sell the Electric unit to someone that needs that type of machine for their own private tennis court or bowling green at home as it requires no restoration to use it as it is. Sadly electric machines are not viewed as highly desirable by the lawn mowing public at large and are only wanted by people with a specialist need.

One thing, and thank you Deejay for the picture of the Villiers with the air cleaner on it, am I correct in saying that the current carby fitted is a wet oil filled unit that picks up its air around the underside of the perimeter of the oil bowel ? as that is very old school to me, but then again so is any Villiers engine I guess compared to Honda and Briggs units.

Now the magic crank handle, yes I was given this rusty item (yes I cleaned it, I have a habit of doing that before I take photos) along with the original air filter. I have to ask the question, what is it really used for as the engine is a rope start and is the original power plant I'd say.

BTW is it possible to get a larger version direct of that lovely old Supercut ad photo ?

Also in finishing the paint on the alloy cover should be red as stated by Deejay and also am I correct in saying that the internals of the catcher were not red but simply green as is the rest of the machine, and the decal on the catcher I've never seen. Bit of poetry there, not intentional I might add.

Cheers for now,
BB

Hi BB and ODK members,

I hope the PM might help you with the parts you may require to complete the restoration.

Thanks for the pic with the crank handle in position, that is correct...and how you start the machine....you just turn on the fuel, disengage the cutter and drive clutches, set the choke and wind the crank handle...no rope, no fuss...easy-peasy!
The handle when not in use, slipped into a receptacle at the base of the right hand handle bar.

The colour scheme in the pic is correct in regard to the catcher internals when the machine was introduced in 1950...it was red, as was the upper lip of the grass deflector.
The decal was the Scott Bonnar 'Aussie Flag' type which was current at the time....The chain-case alloy was polished and the rear roller was finished in silver.
The chain-case attachment hand-screws were always painted green.
As requested, here is a larger pic...

Hi Deejay,

You've beaten me to the next question I was going to ask and that was about the loop attachments at the lower area of the RH handle bar mount point but as you've mentioned it is the receptacle for the crank handle.
My engine does have the rope winder and as such I never thought about starting it any other way. I must admit that the Supercut has opened my eyes and also my knowledge base on earlier Scott Bonnars as I've generally only mastered the Model 45.

One can certainly see how SB cut back on engineering costs and also made the machine much more manageable to the average home user by releasing the 45 and even now many people find the 45 a cumbersome machine to handle, well I guess they've never man handled a Supercut.

Once we've finished moving house and I've got my new workshop up and going this Supercut is going to be fully restored and brought back to its showroom state along with a few 45's I've got stripped down with all parts bagged up and boxed ready for rebuilding.

BTW thank you for the PM with those contacts for the Villiers engine, I must admit that a Honda would be far superior but it just isn't original and a good representation of our Scott Bonnar Mower heritage.

Cheers,
BB

Hi BB,

This Supercut will make a great restoration as it is all complete, right down to the scraper for the front roller.
For the catcher, you can easily have a section replaced by any good sheet metal worker, if it has damage beyond repair....rust etc.

I like your sentiments regarding the Scott Bonnar heritage, and the Villiers, once repaired and well maintained, should give good service...however, as you will realise, they can be a little pernickety at times!

Please keep us updated on your progress with plenty of pics please.

hello B.B, the carby fitted to your 412 engine is correct. MK12/1,12/2 and the 412 were all fitted with the B.10 carby.the spec no 584x is a standard off the shelf engine. I have a spec listing for the 555x engine as scott bonnar,and the only special component was a different gov.spring, so I would assume that this engine also had the B10,carby.
regards, john.

Hi John,

Thanks for that info regarding the carby and to tell you the truth I'm kinda glad I don't have to change it back to make it original. So why I was given that earlier air cleaner is a bit beyond me as I'm wondering where it came from in the first instance. The mower was given to me from a woman whose father bought it new and used it for years until his death 5 years ago. Another thing that puzzles me is the change of the fuel tank from the original barrel type to the Kieby Lauson unit taken from a Model 45.

Do you by any chance have the original tank and mounting straps that suit the 412 engine available for me to purchase as I would dearly want to put it back to stock as I doubt there would be another Supercut out there that is in a fully original and showroom restored state.

Cheers,
BB

Hi Darryl,

Thanks for your support regarding my intentions to fully restore the Supercut. As far as the catcher is concerned it's in fabulous shape apart from a bit of panel beating required. My son is an apprentice beater so I'm sure it will be a good piece to hone his craft on. Hopefully John can help with a replacement tank and mounting straps so that I can get the Villiers back to original.

One point I've noticed on some other pictures I've found on this site of other Supercuts is the rest mounts for the crank handle, mine has those mounts inboard of the right hand side while others have them outboard so that the handle could be easily hit as the mower passes shrubs and bushes etc.

The following shot is an outboard mount version of the crank handle

Hi BB,

That is an easy one to explain mate.
You will notice that it has a Villiers that is mounted back-to-front when compared to yours, and is a clockwise rotating engine driving a double 'V' belt pulley to the large pulley on the counter-shaft, on the right hand side of the machine.

Your machine is driven by an anti-clockwise rotating engine with a small chain sprocket to a large on the counter-shaft,on the left hand side.

If the crank-handle was placed on the inside as yours is, it would interfere with the large double pulley and side plate, because of the handles length.
It is easy to see that in the photo.

BTW, you will see that the Supercut in the photo also has a toolbox mounted on the right hand handlebar, I noticed in your pics, that both your petrol and electric don't seem to have one fitted.
I don't know if they were an optional extra or a standard fit...but you will notice in the original advert in my post above that it is not shown.

However, it is depicted in the Model 17 (Petrol) parts list shown here as part number 139 with the clamps (2 off) as part number 140.


I have had 2 Model 17's in my time (in fact I still have my 18" electric) and both have had the toolbox. I removed it from the electric and fitted it to my Model 45.
Here's a pic...

You may care to check with the lady you got the machine from, it may be hiding in the shed somewhere....
Good hunting BB,

Hi Darryl,

Can you inform me as to how the toolbox is attached ? Would the handle bar have a hole through it with a bolt protruding from the box through the handle bar and a wing nut that tightens up to hold in place because I've just looked at the machine and there are two very visible witness marks as it had electrical tape wrapped around the handle bar. These marks are about 7 inches apart.
I still have the previous owners phone number so I could still contact them and send a picture of yours via E-mail to them to have a look for it if it was indeed fitted previously.

Thanks again Darryl.

BTW that photo I've posted up actually looks like an Electric unit that's been converted to petrol as the Electric mower uses a full width drive shaft with two belts.

Cheers,
BB

Hi BB,

The toolbox has been mounted in various ways, and yes, through the handlebar as yours has is one of them...the one on my electric was by 2 cast fittings (part numbers 107 and 105 in the parts lists above, with the nuts inside the box with spring washers) and also mounted using 2 'U' clamps which is also on the parts list.

That mower in your pic is original with the petrol engine, we had 2 of those used as greens mowers at my local golf club, both had the double 'V' belts and the clockwise rotation Villiers.

By the way, through research this morning I have found that SB produced a 24" Supercut with a Honda engine and Villiers engines.
More to come on this. I haven't managed to get a pic unfortunately.

Hi again BB,

In fact mate, there were 29 models of the Model 17 Supercut manufactured by Scott Bonnar at the Thebarton factory in South Australia....

Here's some interesting info on the models...


All good stuff...

Hi Darryl,

Thanks for that. well that then confirms that mine did have the toolbox attached at some stage as those 1 inch band marks around the handle bar suggests that something was attached for quite a number of years and then removed. I definitely think you are correct in saying that it was optional as my electric unit is totally original and they are absolutely no witness marks at all of anything being attached at any stage of its life.

With this model listing it seems almost certain that mine is a 170413 unit. It's amazing of how many configurations that SB made of the Supercut which now makes sense why each one you see is slightly different to another. I guess as they were made for industrial applications there would be so many differing requirements from contractors etc. that they had to make so many variants.
BTW my electric 20 inch is a 170114 model.

Gee I'm loving this old heritage stuff you're digging up. It just adds to the history side of things so much.
BTW I'm involved with a History Committee at an SANFL Football club and thus you can probably understand where I'm coming from.

Keep it coming Darryl.


Cheers,
BB.

Hi BB,

Just a quick note, I will be placing all new information I find also on the Model 17 Supercut in the "Old Soap Box" on the History Forum which will be placed in "Machine History" in due course.

Hi Darryl,

Thanks for that, sadly there's not a lot of info on the site regarding the Model 17. I guess that's because there's not that many of them around (due to their original cost compared to other options back then)and that they were poked at the industrial market opposed to the domestic, thus there's not much discussion on them. Anything you find on them can you please put something on this thread so that I can see that I'm looking for something new you've posted.

Cheers,
BB.