OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Reel-Type Mowers Scott Bonnar 45 - Some Advice Sought

Just Joined today.

I bought this 14" SB 45 in about 1995 but haven't used it consistently since then as it has spent time in storage and was on loan to my son who didn't make much use of it. It recently came back to me and I've been using it weekly all summer. It runs well but needs sharpening.






One thing that I am wondering about is this bent reel blade. My memory is that it came to me in that condition and was sharpened once in its time with me. Any thoughts?

G'day Sven

This is an important machine for 45 history.
The low Mower Number - 130 - puts this at the earliest
date that the 14" was moved from Kirby back to Briggs engines.

I have recorded numbers 1215 and 1303. You have 120 or 130?

What we would like to know is the model,type and code.
These are the stamped numbers on the air cowl below the air filter.
These should tell us when the 14" was re-powered with Briggs engines.
[The 14" was first powered by Briggs, then Kirby, then back to Briggs].

The reel and bottom blade certainly need attention.

Many thanks for your post and images!

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

Hi Jack,

The number is 00130.

I will take a look and post the other details tomorrow.

Cheers,

I'd have that reel blade straight in about 90 seconds flat.

Cheers,
BB.

Hi all,

I'll put my dibs in and say that this is a late 1975, or early 1976 built machine. The throttle has been changed at some point in time as this one should still have the chrome Villiers style controller.

Cheers,
BB.

Hi again Jack,

The numbers are: 80102 0224-01 73100903

Cheers,

Hi Sven,

I pretty much stand by my appraisal of this machine and that is that it's a late 1975 ~ 1976 machine but with an engine change at some stage in it's life.

The date of the engine correlates to the 9th of October 1973 and at that point in the Model 45's lifespan Scott Bonnar was using the Kirby Lauson engine across the full range. The other interesting point is that the fitted Briggs seems to be a 2.5 Hp powerplant which was the engine fitted to the 17 inch machines while the 14 inch machine used the 2 Hp variant and also in earlier times during the Series 1 45 they used the silver finished 60000 series 2.25 Hp as well as it was whatever SB could buy at the cheapest figure direct from Briggs at any given point in time.

I can't clearly see the sticker that's fitted to the front of the engine which has the Scott Bonnar name along with the machine size on it. This would be interesting to clarify if it says 14 or 17 inch on the remnants of it. Maybe if you so kindly could Sven, can you supply a close up photo of that sticker.

With the code you've given this can't be an original marriage of the two components and as such we can never absolutely clearly identify the build date of the said mower. Can I ask that you can supply us with a clear photo of the actual engine code in question

In saying all of the above this doesn't distract from what is a great mower. One thing to take into account and that is most machines of this age have had an engine swap at some stage of their working lives.

Cheers,
BB.

There's not a lot of the sticker left BB but there is the remains of a '4' on the left of the sticker:



Engine Code - 80102 0224-01 73100903:

G'day Sven and Mod BB
Many thanks Sven for the generous co-operation you have shown.

We have every reason to believe that the engine is original, but the
starter cannot date to the engine block or sticker. The original starter with
its Model, Type and Code has been lost.

Nonetheless, I have a match for 450511, mower number 1303, with a
10/75 engine build date. Given engine shipping times, that machine
would probably be a early 1976 mower build.

I speculate your engine dated from about the mid previous year for
a mower build after September, 1975.

I believe your machine is a late 1975 machine introduced as part of
the 1976 Model 45 range.

This means this is an early example of a Model 45 powered by a
Series 8 Briggs, and introduced for the 1976 season.

Congratulations.
----------------------------
Jack

Hi Sven and Mod CJ,

After much consultation between Jack and myself offline we both came to the conclusion that your Air Cowl with the starter has probably been changed due to a failed rope and thus for many mower shops it was just easier to cannibalise a dead engine for it's bolt ons so as to quickly fix another that's come in the door.

So with that your identifying details have been lost forever. We all agree that the engine block would still be the original to the chassis, but in the end it really doesn't make much difference at all does it and if we hadn't identified this no one would've ever been the wiser.

Cheers,
BB.

Many thanks BB and CJ for your considerable efforts at identifying the engine and its non-original air cowl.

Just one minor matter for my further education: is it a 2 HP or 2.5 HP engine?

I strongly feel it's a 2Hp engine but honestly you'd never know the difference between a 2 and 2.5.

There's really nothing in it.

Cheers,
BB.

G'day Mod BB and Sven
I certainly agree with Mod BB about the confusion here.

This is the thing...
All the evidence points to a 2.5 hp engine.

It makes perfect sense - given this is the larger 8 Series.
The first 14" Model 45s were 6 Series. That's 6.65 cu compared
with the larger 7.75 cu for the 8 Series. You can see the correlation
between cu and design series.

The second factor is the carby system. The lower hp engines had vacujets,
whereas the larger hp engines had pulsajets. The 450511 had the 8 series,
but with basic vacujet, that relied on displaced volume to pull the fuel into
the engine. The pulsajet had a diaphragm to assist fuel delivery.

The third factor is marketing. The 8 series could easily be detuned
(for marketing purposes), and the 8 Series engines on Lawn Kings
displayed as 2hp!

The gallery below shows the other two 450511 14" machines I have recorded.
Both have 2.5 hp engines, both are type 0233-01. Also note the earlier
mower number has an engine built in August, 1975.

This is why I have dated Sven's mower to the start of the new season,
sometime after September 1, 1975. I believe it was a 2.5 engine.

The significance - for me - is that the 450511 was the last Model 45
14" made. It would disappear as Challenge Corp replaced it with
the Morrison mowers of the late 1970s.

That's my best guess.
-------------------------------------
Jack

Thanks again CJ and BB.

Cheers

Hi Jack,

I'll live with the 2.5 Hp outcome but still remain defiant that the air cowl has been changed as the date is just incorrect.

I'll have to wave the white flag on this topic as it was I that originally supplied the photos for one of these two examples to you Jack. The set that shows the mower in the doorway with the red bricks in the background, as that lot gave us some valuable info about the last of the 14 inch variant before SB scrapped it along with the 20 inch example and substituted them for the Morrison designed machines as you've pointed out in the above post..

Cheers,
BB.