OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Reel-Type Mowers Restore or upgrade the SB's?

Howdy to all the SB aficionados,

This forum certainly is a valuable resource, I am only new to the world of Scott Bonnar, but am a lawn lover from way back. I have recently acquired 2 Scott Bonnar 45's, one a 14inch and the other a 17inch. They are old, obviously... and I think the pair are some of the earliest models from what I can tell through lurking the forums for a few weeks. Unfortunately, i don't have all the information on hand at this point but the 14" engine is number is 60102-0302 and the 17" engine number is 80102 0233-01 dated 7510010. Mower and model number I can provide later on.

The 17" is in reasonable condition, starts first pull, nice and true and cuts well. From all reports, the 14" runs well, well it did when it was last started 12-months ago. But I couldn't get it going in the 5 minutes i had available at the time. Again, it is in a reasonable physical condition.

I was looking for opinions on a restoration process. There seems to be a popular method of engine upgrade by replacing old with new be it a Briggs or Honda on both this forum and others around the traps, which I am not totally against. But from a restoration point of view, rebuilding the original engine seems more sympathetic to the machine.

Over the course of the next 12-months, I would like to restore the 14" model and gift it to my father, or keep it if I do such a good job and don't want to part with it! The extent of the restoration is up the air at the moment. I have seen some epic restores on this forum which make me salivate, but time, money and my skillset will play a big part.

The 17" model i will keep for my own use. The current 2.5hp 80102 engine dated from '75 is in good knick and goes well. I was thinking of upgrading this engine to a new 3.5hp B&S bolt on and beginning the restore on the original with the intention of installing it on the 14" model as an upgrade. I would love to bring it back to out of the box condition and I think the original 60100 engine is well gone and probably underpowered.

Would love some opinions from the experts.

Cheers
Jim

A couple of pics of the 17"... please excuse the beat up catcher. It will need to be replaced. She's past a panel beat me thinks...

Hi bluezoy,

It is incredible how many SB45's have surfaced here on this forum over the past couple of months with it being summer (boy I'm looking forward to Winter and being a bear)

The 17 inch machine has been used as a battering ram and not a lawnmower it seems. That would have to have the flattest front I've ever seen on any Scotty.
Now with that one I'm not sure if that's it's original engine as it looks to me to be an apple green 45 and that colour didn't come out until around late 76 and your mowers engine appears to have been made on the first of October 1975 which would mean the mower itself would've been made around late January early February of 1976 and at that point in time the machines were still being painted in Alpine Green (darker green) and with a black chaincase and handlebar shield.

So the Jury's out on this one as it's not conclusive.

As far as the 14 inch machine is concerned you've left off the vital 7 last digits of the engine code so that can't be dated and also some photos are essential to evaluate it.

Cheers,
BB.

Thanks for the reply BB,

I will get some photos of the other machine tonight and see if I can see all the numbers. The photo I took in the dark the other night didn't allow me to see those vital 7 digits.. The catcher has had some home panel work completed clearly. The corners had rusted out and as a fix it looks like someone folded in the corners and added a couple of welds. I assume the lack of metal meant it flattened out to take up the space left by rust.

I am interested in your dating system. I am surprised at the speed the engines went from manufacture in the states to installation on an Aussie built mower (3-4 months). When did they start painting the Alpine Green colour?

I will get all the numbers of both machines this evening and report back.

Thanks once again.
Jim

Hi Jim,

Normally it took around 3 months from the Briggs plant to the customer in Australia, that being Scott Bonnar. Now being that your engine was built in early October 1975 that would've made it late December for delivery to Thebarton in Adelaide. Then one must consider the Christmas Close down from around 23 of December and over most of January, things would've been slow at that time of year, thus I'd say the mower would've been made (assuming that engine is the original unit )around early February 1976.

I must say the photos are not that good lighting wise and it could still be a Alpine Green unit as the sun is making it rather confusing, but one thing is for sure it should have a black chain case and shield for that era and not all green.
Pentagon Logo on the catcher is correct.

Cheers,
BB.

Some more images of the mowers. In different light to see if that changes your view of the colour. The chain case does look as though its been repainted. Where paint has chipped you can see black underneath. So this could ring true to your comments BB. Although, the shield is original in colour, so perhaps a retrofit.




The rough as guts 14".


The full string of numbers off the 14" engine is 60102 0302 01 7108093. Mower # is 45 31174.
The 17" is engine as mentioned earlier and Mower #08610, Model 450520 (this is a newer plate, definitely not the original, were these often replaced, perhaps by an official service centre?).

Cheers guys.

I'll have to say that the green is a real odd ball green and I was actually wondering if it's been repainted some years ago as it's rather knocked around. I feel that it's been through a mower shop some time back and been spruced up as the black chain cases and handlebar shield looked hideous IMHO.

The era that the engine was built is concurrent with the 2.5 Hp that was used around early 1976 as just after that era they changed the engine to a 3 Hp and fitted the restyled handle bar with the lower kink in it.

So all in all it may be a rather original machine bar the paint on it.

Now that 14 is ugly indeed, again we can't really pinpoint the date on that one as the air cowl seems to have been changed along with the air filter housing. Maybe you could scratch the black and see if it's got much the same silver underneath as the fuel tank and the engine block.

Regardless it is a Series 1 model 45 and was fitted with either a 2 Hp, 2.25 Hp or the least likely 2.5 Hp engine when new. It looks as if it's missing it's main drive chain tensioner which you'll see once you open up the chain case.

Cheers,
BB.