OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Reel-Type Mowers Another SB45 restoration newbie

Hi there,
Being a long time rotary lawnmower user, I recently purchased the following SB for $250 - goes very well & I've quickly grown very fond of it. I understand it's called a Scott Bonner Lawn King.







I recently discovered this very awesome forum (& the Youtube videos) which has inspired me to try to restore it. A few questions if I may:
- What does the machine number indicate? age?
- Does the blade look like it's got enough "meat" to warrant re-sharpening (rather than replace)?
- Is there a way of removing side cogs without a gear puller?
- Is there any easy way of finding out how many HP the B&S engine is?
- What's the best way of preparing the chassis for repainting? Do you sand back to bare metal? or just remove rust / abrade & paint over with hammertone?
- Any other observations about the machine / info / help is much appreciated!
Cheers!

Hi Lewy71, and a warm welcome to the forum.
It's always nice to have another Scott Bonnar owner on board.
Your machine is a Scott Bonnar Lawn King, manufactured in Thebarton, South Australia, it is (what we call) a 'twin rail' engine deck with what I believe to be a 3HP Briggs and Stratton engine fitted.

To confirm this, we need you to post the complete string of numbers stamped into the metal air cowling, which will be the Model, Type and Code.

From this we can give you the date of manufacture of the Briggs which will then give us the approximate date of your machine (as we cannot date Scotty's accurately as no records were kept) See the pic here:


Your cylinder reel has plenty of 'meat' in it, but will probably need to be re-ground sometime in the future. You may need to use a 3 leg gear puller to remove the engine (12 tooth) and the double cutter sprockets.
Please refer to our video guides that can be found HERE

For repainting, many members have the chassis sand blasted, primed and re-painted, others may just sand and re-paint. Other SB members here may give advice here.
Once again, to OutdoorKing.

Thanks for the response Deejay - Was wondering where the engine number was - will get back with that.
Can't wait to get stuck into it!

Hi Deejay, engine number is 60102 0347-01 74061401.
Manufactured in 1974.
Does it tell me hp?

Hi Lewy71,
This confirms your engine is 6 cubic inch displacement, basic design series 0, horizontal crankshaft, vacu-jet carburetor, plain bearings and rewind starter which was manufactured on the 14th June 1974.
The 60102 would indicate that is a 2 to 2.5 HP engine.

Hi DJ and Lewy71,

Lawn Kings were basically all 2 Hp units as they were a budget Package Machine sold to a price while the "Fully fledged" Green Scott Bonnar's in the 17 inch cutting width were all 2.5 and 3 HP powered machines.

The only differences were the Pram Handle Bar opposed to the winged version and the colour being Pacific Blue in the model 45 variant, apart from that it's running parts are all identical to the SB green machine.

Cheers,
BB

Thanks Bonner Bloke! I'll be ordering the 2hp b&s decals. Cheers

Hello Lewy71, Deejay & Bonnar Bloke

As BB said, I believe the earlier blue45 Lawn kings had the 2 h.p. decal ...

However, The B&S 6 series engine did appear as a 2hp or 2.5 hp - as Deejay said.
My records show the later green 45 Lawn Kings (and Craftsman) machines had the 2.5 decal.



All very interesting.
-------------------------------
JACK

Thanks Jack

Hi all,

Yes I did forget about the Grey Lawn Kings didn't I ? I guess that this was due to the issue of Lewy71 having a Pacific Blue LK and not deviating away from what he had as there were so many variants of the LK from the earlier times (Kirby Powered units) right through to the end of them.
If I'm correct the 2.0 Hp was dropped as the 14 inch mower was deleted and thus there wasn't a requirement for that size engine and a 2.5 was a better option for the larger 17 inch units.
There were though quite a few 14 inch machines that ended up with 2.5 Hp power plants and also in the earlier Silver motor version also as a 2.25Hp as well.

I know that I'm venturing off the original path now so I'll quit before heading out into the desert LOL !

Hello again,
My SB is now in pieces, & have encountered a little problem removing the clutch housing from the engine crankshaft.

I have studiously watched your video (& read a couple of posts) to try & solve the problem myself, but no joy as yet.

My question is in relation to the 3 screws on the clutch housing (see photos below).





In the 1st photo, is the cotter pin - I have tapped this in as far as it will go & subsequently have no luck trying to tap the clutch housing off the shaft.
I don't understand what the other 2 bolts do (in 2nd photo). They are 2 bolt shafts sticking out from the blue casing, with nuts on them (when I unscrew the nuts, the bolt shafts remain in place). Do you know what they are for & do you think they might have something to do with me not being able to remove the clutch?
Cheers,
Lewy71

Hi Lewy71,

You are absolutely spot on with those extras not letting you remove the clutch half.

This is a previous tenants idea of either fixing a wobbling clutch body or seeing the newer design and trying to copy it.

Those extra lock up grub screws are what's is pinning the body to the shaft.
You will have to undo the nuts and then use an allen key of the correct size to unscrew the grubs out of the casting.

Before you go any further with this clutch body I'll have to ask you, do you think the body was revolving absolutely true or did it already have the slightest amount of wobble when revolving ?

The body you have there looks to be the first of the die cast bodies that were substandard compared to the predecessors that were manufactured out of cast iron and thus much more robust but far more costly to produce.

Personally if in any doubt what so ever I would discard it and replace with the current style unit that utilises two set screws that pin the body to the PTO shaft at 90 degrees to each other and not allowing any play to eventuate.

Cheers,
BB

Thanks BB - makes complete sense.

Thanks BB, that is excellent advice...this machine, once in excellent order, will give Lewi many hours of mowing pleasure!

G'day,
Has been a while since my last post - footy season has kept me busy & away from the Scott Bonnar project, which I've recently had a chance to get back into again. Since I last posted, I have done a few things:
- Pulled the machine to absolute bits;
- Ordered engine & chassis decals;
- Ordered new muffler, carby/fuel tank gaskets, clutch half, thrust & cutter bearings & rubber stoppers;
- Stripped whole chassis with paint stripper / wet & dry.
- Degreased, partially sanded with wet & dry & repainted engine chevy engine orange (see below);
- Stripped & very crudely repainted cutting reel (fire engine red).
- Sprayed the chassis white knight hammer finish blue (see second photo).





The only hiccup I have had so far is one of my dogs spewing on the chassis when the paint was curing! The dog spew had acid which etched into the curing paint, so had to repaint it.

Hopefully I can get some time this weekend to start putting back together.

Have to say that I, as a non-mechanical person, am finding the process of restoring the mower very satisfying. I have been recommending this type of project to a number of my fellow white collar workmates as therapy !

Hi Lewy71,

Ah yes the Footy season, it's certainly a distraction I must admit, honestly I can't believe it's just about over again for another year and we're still right in the middle of winter weather as well.

The progress on the engine looks superb I must say, now the paint colour on the chassis parts looks a tad odd, may I ask what colour it is ? Are you trying to replicate the original "Pacific Blue" that your Lawn King was painted in or have you just chosen something that you preferred ? Which ever way it is it's your therapy and it's got to make you feel better doesn't it.

BTW the dog story is an absolute ripper but I'm sure it has frustrated the living daylights out of you. Oh well that's just how it goes sometimes, also great usage of the kids scooter, just hope he or she didn't want it while the paint was still wet as then there would've been your next drama.

Looking forward to more progress shots.

Cheers,
BB

Hello Lewy71 and Mod BB

As the Forum Historian, I have noted the first recorded case of a lawnmower
paint-job being interfered with by dog vomit. What was he/she thinking?
[Was it jealousy? In advertising the 45 was described as a ... 'new breed'.]



On a more serious note, your comment on a 'white collar' worker gaining
satisfaction out of restoring a lawnmower is both interesting and welcome!

All very restorative.
----------------------------
JACK

Hi BB,
Regarding the paint job, I had a choice between 2 hammer finish blue paints at the local Bunnings (White Knight paint) v Supa Cheap Autos (more of a brighter blue). I ended up going with the White Knight paint because the "Scott Bonnar Lawn King" decals I ordered off Ebay had the exact same coloured blue background. Neither the engine paint, or the chassis paint are exact replicas of the original paint colours, but were pretty good value (at about $20 per can).

Will keep you posted.

Hi Cyberjack,
Thanks for the Far Side cartoon - Awesome!
Maybe Dino was feeling jealous - in which case, thankfully he only spewed on it! (& God knows what he might have done if he felt attracted to it).

Hi there!
Picked up the sharpened blades & got a few hours on the weekend to start re-assembling the machine. Progress so far: