OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Question On Scott Bonnar Cylinder Mowers Another Scott Bonnar Lawn Mower 45 series rebuild

Hi guys,

New member here. Just purchased a old run down Scott Bonnar 17" Cylinder mower model no. 450589. Planning to rebuild this mower.

1)Is there a new reproduction of the Grass catcher that I can buy?
2)Looking to buy a new heavy duty replacement cutter cylinder? any recommendations?

Thanks in Advance

Peter

Hello SBN45,

A big Welcome to the ODK forum.

To answer your questions, there are new aftermarket replacements catchers made which are for sale from various sellers on eBay. Their cost is over the $100 mark though, as for the cutter reel they are definitely not cheap and really there is no need to replace your existing unit if it is not bent out of shape / damaged and has enough meat left on it. A better close up photo of the reel and surrounding area would be beneficial for us to evaluate it as there's no point in throwing money away on something that really isn't needed.

Looking forward to seeing more photos of the machine in general and also some close ups with the chain case removed.

Cheers for now,

BB

Hi BB,

Thank you for your reply. I will take some more photos today and post them up.

Is there any advantage in changing over to a 8/10 Cutter reel? ie. Will my lawn finish be any better? Regarding the aftermarket replacements catchers, has anyone brought a aftermarket galvanized steel grass catchers for Rover & Scott Bonnar cylinder mowers?

Also where is the best place to buy new spare parts?

Any help will be greatly appreciated.

Peter

Hi Peter,

For a standard lawn there is absolutely no benefit at all changing up to a 8/10 reel. These are basically only used for super low applications like bowling greens. If you are mowing a domestic Santa Anna Couch lawn then the standard reel is perfectly OK as many will testify to.

As far as catchers are concerned there a couple of sellers that regularly advertise on eBay and they are priced reasonably well to sell.

As far as spares are concerned they can be bought right here in the online shop, especially some of the more specialised parts like sprockets and chains etc. There are no body type panels available, eg. grass deflectors, chain case covers and so on. These have to come from other machines that have been beyond repairing and as such are being parted out.
There are quite a few sections in this website for "Wanted to Buy"/ "Sell" etc.

Hope I've been of help. If in doubt don't hesitate to ask as there are plenty of knowledgeable guys on here.

Cheers,
BB.

Hi BB,

Didn't realise that this forum has an online shop. Picture of the chain case removed.

Hi SBM45, and a warm welcome to the forum. It's always great to welcome another Scott Bonnar model 45 owner on board.

Your machine is the Series 2 (twin rail engine deck) Model 45 made in the SB Thebarton factory in South Australia.
If you could post the model, type and code numbers stamped into the metal air cowling of the B and S engine, we can give you an approximate age of your machine. The numbers are in the location usually near the intake manifold...please post the whole string of numbers.


As far as the chains and sprockets are concerned, I would need to see a close-up of the sprockets, where they are not covered by the chain, so as I could assess their condition for you.

Once again SBM45, to OutdoorKing.

Hi Darryl,

Thank you for your warm welcome. Happy to be part of this forum family.
Will get a photo of all the numbers. Not sure if this black coloured case cover is the original cover??

Got my inspiration from my fathers Scott Bonnar. Will post some pics of his joy and pride.

Hi SBM,
Thanks for your reply and I'm looking forward to seeing more pics!
It will be interesting to see if that is the original cowling....we may be able to tell from the numbers.

My fathers Scott Bonnar 45 series, Purchased new back in 1978. Subaru Robin engine added recently.

Hi SBM45,

I'll have to say that the very top sprocket looks as if it's seen better days and could do with replacing as the tooth profile has worn to a very pointy profile as also has the cutter sprocket. Both these two are available in the online store. As Deejay has hinted I'm wondering if your motor is still in fact the original unit, if not then you'll never know the manufacture date of the mower.

Anyway once we get those numbers we'll be able to get a better idea as to what the date is.

Cheers,
BB.

Hi SBM,
I think the Victa sticker on the air-cowling might be a dead giveaway plus the B & S signage that is upside down and the pull handle position, that this is definitely not original to this machine....In fact it came from a vertical shaft engine, manufactured in 1991.

Your Dads machine looks great with the new engine fitted, however, I am not sure about the checker plate addition to the grass deflector....what is that for?

Hi again SBM,
Re: the sprockets....I would have liked a more close-up pic of the sprockets, but from the pic you supplied, I would agree that the top (small) primary sprocket and the double cutter sprocket plus the primary chain, will all need replacing.

Hi Deejay,

The top checker plate was added to deflect grass into the catcher. Stops cut grass falling back onto the machine in windy conditions.

I don't understand why the build information will be stamped on the air cowling when this could be interchanged with other motors.

getting some more photos this weekend, when I pull everything apart.

Hi SBM,
That is the way Briggs and Stratton have done it for years...if the recoil starter can be repaired, there should be no reason (other than external damage) that the air-cowling should part company with the engine. I suppose they have to put the ID info somewhere.

Hi guys,

I guess that the cowling was the cheaper alternative, as to stamp into cast ally would be risky of fracturing the casting and the cowling is made of steel. Just my opinion.

Cheers,
BB

Hi SBM45, I went through the new reel saga a while back and found it hard to source a decent original 6 blade reel for the 17", at least one with minimal damage. I found the easiest thing to do was buy a new one but getting a new 6 blade is almost impossible. You can get 8 blade reels on eBay but i found a brilliant reel mower bloke in brisneyland and bought a 10 blade off him. I paid $320 for mine.

Hi muppetsdad,

Second hand parts, especially good ones, are hard to come by for the SB model 45 as they snapped up fairly quickly.
But most (if not all) new parts are still available for the 45, (with the exception of chassis, chain-case cover etc.)

In fact, we have new 6 blade cylinder reels (OEM part number A451581) in the OutdoorKing Online Store at present.
The 10 blade reel does not suit all types of grasses, as you would most probably know.