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#92931 15/09/18 05:48 PM
Joined: Dec 2016
Posts: 90
Trainee
Against all advice, (thanks BB) I have begun to look at the rebuild of this machine. Far more complicated than the 45 or Supercuts were in that it doesn't really make sense in any straightforward sort of way.
Has anyone else had much experience with these? I know that they are unpopular and I can see why.
Jack, are there any instructions on the forum that I might be able to look at? I don't want to simply tear it apart and have no way of putting the damn thing back together if the gearing is actually okay. It looks to me that the driven gear on the rear roller is pressed on, but that couldn't be correct surely.
Any advice would be welcome.
Thanks
John A
aussie

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IMG_3284.jpg (270.87 KB, 116 downloads)
IMG_3283.jpg (222.21 KB, 115 downloads)
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Portal Box 6
John A #92932 15/09/18 06:15 PM
Joined: Aug 2011
Posts: 2,998
Likes: 16
Former Moderator
Hi John,

I'm not sure, but if I recall correctly the drive isn't functioning ?

Cheers,
BB.


I live a 24 Hour lifestyle, but every now and again I seem to fall asleep, well at least that's what my wife tells me.
John A #92956 16/09/18 05:21 PM
Joined: Dec 2016
Posts: 90
Trainee
Didn't test the engine (apart from compression) prior to removing it BB.

I wanted to either rebuild the entire thing or scrap it as you suggested if the gear is no good, so I have proceeded to pull it down, but that is more difficult than I had anticipated.

I can't figure out what to do with the drive pullies as they appear to be pressed on, but I may be getting ahead of myself anyway.

I will rebuild it if the plastic gear is not broken but that seems unlikely given the brittle nature of plastic and the condition of the mower.

I didn't want to break any more than I had to in getting it all apart.

Cheers & thanks for your response

JohnA

John A #92961 16/09/18 08:10 PM
Joined: Nov 2013
Posts: 6,938
Likes: 304
Forum Historian
G'day John and Mod BB
The manuals on this forum cover the Model 430 and 590.

The more rare must be yours - the Model 430.
https://www.outdoorking-forum.com.au/forum/u...-bonnar-manuals-parts-list.html#Post6371

I have been intrigued by the Diplomats for decades.
Against all odds, Scott Bonnar attempted to redefine the reel mower.
Had the budget just been a bit bigger ...

Hope this helps.
-------------------------------
Jack

p.s. pulleys will be screwed on, some with LH threads

John A #92970 17/09/18 06:39 PM
Joined: Dec 2016
Posts: 90
Trainee
Thanks, Jack.

having spent a # of fruitless hours in the shed today, it is slowly coming apart, but I am hesitant to do too much until I know where I'm going with it.
It looks to me like an early attempt at political correctness & like the modern version, is completely wrong
Your manuals should be of great benefit
A couple of numbers came to light as I stripped bits off & you are correct (again) it is model 430 and machine # 1006
It is in surprisingly good nick as far as blades & general condition are concerned & the engine appears to be okay too.
Shall keep you up to speed, but it will be slow going I think.
Cheers & many thanks
JohnA

John A #92976 17/09/18 11:48 PM
Joined: Nov 2013
Posts: 6,938
Likes: 304
Forum Historian
G'day John
I'm all selfish here - well, almost. blush

This is a great opportunity to document a Model 430.

For me, the Diplomats (having won a design award) were let down
by production cost constraints. The most serious restraint was in the
set mechanism - or lack of it. Bean counters appear to have taken charge.

Had SB adopted the most basic system from a century before, they would
have still been in front of the shambles they came up with - with no direct
adjusting system between bed-knife and reel. What were they thinking? mad

The Diplomats do not suffer from lack of quality. The final drive gearing
was brilliant - and probably taken from a UK patent. This is unknown.
The final drive met the objective.

The Achilles heel here is the lack of replacement parts, not any
defect in design or materials chosen. Lawnmowers do wear out.

Diplomats were never given the olive branch that Model 45s have been
given in the modern age.

I have argued many times on this forum that rear catcher power mowers
were not that uncommon, but Scott Bonnar's clever use of space and aesthetics
must go to their credit. The design worked well!

From a safety perspective, the Diplomats act at their diplomatic best.
The reel is almost invisible at the front, and all other moving parts were shielded.
Remove the rear catcher and there is no chance of injury. Brilliant!

Like Shakespeare's Macbeth, we have greatness let down by a fatal
flaw. This makes the machine more human and understandable.

The Diplomats were flawed, but not un-lovable!
They deserve a chance beyond uses in maritime anchoring.

I'm sure you will keep us informed.

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


Last edited by CyberJack; 19/09/18 01:07 AM. Reason: Added thoughts
John A #92996 19/09/18 12:02 AM
Joined: Sep 2016
Posts: 159
Likes: 1
Apprentice level 2
Hi John,
OH good luck with the Diplomat, I had one and a sod of a thing to strip down
I gave up in the end and couldn't give it away
had parts listed on eBay And Gumtree for free but no takes
so it went to the tip
It was the only mower that I have given up on

would make a good mooring lol

Cheers Ken

John A #92997 19/09/18 01:27 AM
Joined: Nov 2013
Posts: 6,938
Likes: 304
Forum Historian
G'day Ken and all

Ken, I'm glad you said that. smile

My points challenge the current historical reality of the Scott Bonnar Diplomats.
I feel history needs to re-assess these models.

Yes, Scott Bonnar should have produced a service manual for strip downs.
The transmission was new and unconventional.

Diplomats have an undeserved reputation.
No wonder no auction interest ... !

The shrewd collector will see through this - I hope!
Maybe not.

Cheers
-----------------------
Jack




John A #93262 29/09/18 07:27 PM
Joined: Dec 2016
Posts: 90
Trainee
Hullo all,

many thanks for your comments and encouragement (from most) & sympathy from others.

I started to strip the mower as I would a 45 or the supercut but have found that you simply can't do that. You have to be methodical. Perhaps someone with greater skill would know this, but I simply went ahead and took off what I could but got to the point where I have to actually think about where I am and have had to put stuff back in order to get a clearer go at it.

The rear roller has to be left attached both sides or the left drum cant be gripped with enough force to undo the clutch/cork plate. The cork and gears appear to be okay as it engages gear as I think it should. Beats me why people get rid of stuff that still has life in it.

The blades came off okay and without too much hassle.

I have found the driven gear on eBay for $50 so will buy one whether I need it or not and the rest should be okay I think.

I've been a bit slow these past few weeks, as my wife was bitten by a spider and we have almost taken up residence with Drs. However, I will have a good crack at the Diplomat over the long weekend.

I have to say that I have gained a little more respect for this little thing as I have gone along.

Will post again when it is all in pieces with photos I hope.

John
aussie

John A #93269 29/09/18 11:49 PM
Joined: Nov 2013
Posts: 6,938
Likes: 304
Forum Historian
Quote
I have to say that I have gained a little more respect for this little thing as I have gone along
Hello John A

That's a well-thought-out thought.
From a historical perspective, I have come to a similar conclusion.

Such an odd composition of good and bad design.

Many thanks for the update.

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

John A #93276 30/09/18 01:50 PM
Joined: Dec 2016
Posts: 90
Trainee
Have spent most of my time working out a way to remove the drum pully but no luck.

I shall post a few photos so that some sequential order might make sense to others who have more knowledge.

There must be an easy way because the clutch cable requires (I think) that the pulley be removed in order to be replaced.

Anyway, here are some photos, such as they are. Only the drum remains now.

To explain why I have attached these pics:
- The collets on the bottom cutting plate need to be removed in order to remove the plate.
- The remaining pully which has the cork clutch plate behind it, looks okay and the cork appears to be fine. The gear locks inside the drum nicely when this is rotated.
- The bolt on the bottom pulley is LH thread.
- The idler pulley comes in 2 parts.
- I noticed that Diablo had trouble removing this shaft on his 590. The keyway kicked up & jammed, but a wiggle or 2 soon released it.

John


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John A #93277 30/09/18 02:24 PM
Joined: Nov 2013
Posts: 6,938
Likes: 304
Forum Historian
Hi John

I guess you've seen this topic:-
https://www.outdoorking-forum.com.au/forum/ubbthreads.php?ubb=showflat&Number=22438&page=all

Cheers
----------------------
Jack

John A #93296 01/10/18 04:05 PM
Joined: Dec 2016
Posts: 90
Trainee
No, I hadn't seen this thread. Many thanks, Jack, it has helped enormously.
John

John A #93297 01/10/18 05:58 PM
Joined: Dec 2016
Posts: 90
Trainee
Thank you, Jack, for advising me of that particular thread.

All apart now and only the cleanup and reassembling in front.

As a note for anyone else who may attack one of these, I used a couple of tapered cold chisels (don't faint here) to drive between the pulley and the chassis - not to cut anything, but they just happened to fit well in the space and the taper allowed for a gradual interference.

Once the pulley was off and the keeper/grub screw removed, it virtually fell apart.

So, I would suggest that the trick is to undo the bearing keeper from the outer side, then the grub screw (which was an Allen head screw on mine) and then pull the pulley off which takes the metal inner gear with it (as can be seen from the pics).

The plastic drive gear comes off when the centre shaft is driven back into the roller by the method described by Kempe (nut back on the shaft and allow the weight of the rollers to force the gear toward the ground) I then used a long podger that I had from blacksmithing days to drive it all the way through.

Pictures follow & thanks again for your interest.

John
aussie

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John A #93298 01/10/18 06:39 PM
Joined: Aug 2011
Posts: 2,998
Likes: 16
Former Moderator
Hi John,

I've never had the chance to pull one of these down but I guess the drive gear has had it's day as it's cracked all around the hub area and thus is probably slipping and no longer providing any drive.

Looks like you'll get to use that gear you've purchased after all. Now the question beckons, how long will that gear last before it to fails ??

If only there were more of those metal reproductions left around to buy and install, maybe then they would've gotten such a bad rap.

Cheers,
BB.


I live a 24 Hour lifestyle, but every now and again I seem to fall asleep, well at least that's what my wife tells me.

Moderated by  Bruce, CyberJack 

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