OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Reel-Type Mowers New/Old Bonnar 45

Hi , I have recently purchased a SB mower from a crafty old fella who said it was regularly serviced and was ready to go to work on y lawn. The freshly applied paint that was not to carefully applied to the mower and engine might have been a clue to hidden problems. Anyway I'm keen to get it up to scratch. Not sure what I've got as there is no Scott Bonner I.D plate on it. If i can work out how to submit photos i will add these to the post. Any advice would be gladly taken and i have enjoyed reading the manny other posts from Bonnerites helping each other to achieve their grass cutting nirvana. I hope I'm not interloping on the wrong site as I'm not very computer literate.

Hello Kerly

A warm welcome to these forums.
Uploading photos is quite easy HERE.

Any problems just let us know.

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

Welcome mate,

That sucks about the dodgy bob seller. Unfortunately this is an all too familiar story many of us run into at one point or another. I once bought an outboard for my boat from "a 4th year apprentice marine mechanic" as I was getting it cheap I didn't bother to test it before buying. I get it home, got it running and water POURED out the thermostat housing. On closer inspection I found the dodgy ar#e hole had removed the thermostat (I assume it was jammed) and replaced the housing with NO gasket AND to make it worse the bolts had obviously sheared so he had drilled them out (On a terrible angle) and replaced with tec screws! Once I had fixed all that it was a good little engine but If I couldn't do the work myself it would have cost me an arm and a leg!

I really hate when people think it's OK to rip others off.

I can't help at all with your project but there are heaps of guys here that can/will.

Pete

Thank you for your assistance. I will get onto it after work tomorrow.

a
some assorted pics of the beast before i started to dismantle.

Do these pictures help to identify the mower? The cogs and chain look to be in good condition. The reel adjusters need to be tapped with a hammer lightly to take up the slack when adjuster nut is backed off and the screw is wound to move reel closer to the bed knife. The mower worked well on mowing the yard, however I have a Buffalo lawn. I was advised by a local mower shop that the 45 would be perfect for my Buffalo grass. I have since found that i need to raise the cutting height above the standard SB 45 to maintain healthy grass. an increase of 10 to 20 mm is required. I can increase the length of the slotted adjuster or increase the diameter of the front roller to eek out some height. any other suggestions?
Thank you.

Hi Kerly,

16th of September 1980 is the date of manufacture of the engine, add another 5 months (due to Xmas break) and you'd be pretty well around the mark of the mowers birthdate (Feb 1981). There is no way of dating it exactly, but there are various items which give us more of an idea. Now looking inside the drive train area we can see that it was originally painted in "Apple Green" which I already knew because of the throttle assembly and the style of SB stickers that are on it.

Now as far as cutting it higher and butchering the mower in the process, this is absurd. My father in law had buffalo as did many people that planted there lawns in the 1930's onwards. Buffalo is nothing new and he cut his massively large lawn with a Model 45 for 25 years or even more I think.

One thing that will have to be evaluated is the PTO shaft on the engine after you remove that butchered clutch half which will require replacing as a high priority. Leaving it like it is will only inflict more damage if it hasn't already done so to the chassis rails due to running unbalanced and inducing stress fractures.

As far as tapping the adjuster set screws is concerned, that's a no no. If you undo the the two bearing carrier bolts very lightly, you'll find you won't have to use a hammer at all. Honestly it's a tool that's rarely used in my repertoire of engineering. The locking nuts only have to be undone a tiny tad so as to reduce the play that you'll induce into the process. All you need to do is adjust it correctly then do up the two carrier nuts nice and tightly, then check the reel to bed knife contact and if satisfactory then just nip up the lock nuts on the set screws and you're done.

Cheers,
BB.

All I will say is your lawn is way too thatchy and needs to be cut right back to a base level and allow it to re-grow. Then set the height you desire and you'll be right. There's no need to modify the mower in any way, just the actual lawn.

Thank you I'll start getting parts list together. The adjuster lock nuts and screws were seized and would not budge for 3 days with WD40 and gentle back and forward action to get them moving. I had not intended to use a hammer as a routine course of action but to see if when the adjuster was backed off the reel would move closer to the blade as it was fixed in place and not moving with the adjuster backed off. I will adjust the bearing carrier bolts. On reassembly i will replace the adjusters and all bearings. Thank you for giving me an indication of the vintage of the mower. I had thought it would be older but a hard life ages everything. Since the initial mow on the purchase day and the discovery of the clutch damage the mower has been out of service. Pending investigations into repair costs ect. mower height of 30 to 50mm are recommended for buffalo grass leaning toward the upper end. My lawn is not old enough to be heavily thatched and in manny places was showing dirt after being mown on the highest setting with the SB. Being in much better condition will alter the cutting action and performance of the mower. However short Sir Walter in hot Queensland weather will soon burn off.

Hi Kerly,

Ah....... it's Sir Walter and not just standard buffalo, that wasn't made aware to me and as such it's a hybrid version of buffalo. Yes now I understand.

I must admit that I've never had the need to raise the height of any Scotty past it's height end of travel.
I'm going to have a look at one of mine and see what the best way of doing it as I'm not a big believer of hacking things to suit my own needs.

I'll get back to you on this one.

Cheers,
BB.

Thanks for your reply
I do not consider useful modification to something in order for it to perform a given task hacking. I have no intentions of throwing my money away by butchering something that i value. Modifying things to suit our needs is how we evolve with the goal of improvement.
I have no desire to hack and destroy the machine. I would much prefer to restore to factory and have happy trails. Given this may not be suitable for my lawn, I am looking into the best method of making the machine fit for task.
Thank you for your assistance.

I removed the B&S today expecting to find cracks to the mounting holes and did on one bolt hole. There appears to have been repairs made to the engine mounting holes in the past. The chain that drives the reel does not have a joining link in it. It had to come off with the top cog. I will need to get hold of a puller to remove the remaining 2 cogs for the rear drive roller and the reel. Sand blast and repair the crack.

Hi Kerly,

Firstly I'm not accusing you of being any sort of a negative influence, but on these forums you must appreciate we've seen it all, some of the most horrific acts of so-called improving things.

We here are in a position where we can not give out or endorse any type of non factory modification that can render a machine dangerous or not be used outside it's original parameters.

Yes it is OK for other members to do and say things, but I am in a position of liability and can not bring the ODK into a predicament of disrepute.

I hope you can understand that and please do not take what I've said with any intention of malicious.

Cheers,
BB.

Hi Kerly,

Congrats on buying what is a great piece of machinery once restored will perform well.

Unfortunately in my experience your problem is not with the mower but with your lawn. Sir Walter is just not a lawn that gains too much from a reel mower (in my opinion). You can use it but you will have issues. Raising the cut height will help with lawn health, but will also largely negate the benefits of using this type of mower in the first place. There is a reason these mowers only cut to a certain height and that is because they become less effective at higher cuts.

I have a yard of Aussie Blue (similar to Queensland Blue) surrounded by seas of Sir Walter in my street in Brisbane. When I cut my lawn I also do a section of sir Walter on my neighbors footpath. Frankly, there is little real difference between the section I cut with a reel mower and the sections he does with a rotary. At best you could say the leaf cut is sharper with the reel mower, but as the Sir Walter is fairly broad leafed and woody comparatively it does not make much of a visual difference.

If you had not stated that your lawn is new, I would have suggested you change your lawn rather than your mower, but that may not be a palatable option, although don't write it off without consideration. I have a few neighbors who are now actively planning to remove their Sir Walter.

Kerly, don't let your lawn dishearten you, because I'm a strong believer in that any lawn can be trained to grow a certain way. Sir Walter can become a problem, however, if you commit to mowing minimum twice a week, trust me, it'll look better than a rotary will achieve, and you'll also achieve a nice low cut. the first few cuts may result in scalping, but with plenty of water and gentle care, it will look fantastic.

I have Kyk throughout my place, and to be fair - a little bit of couch. Many have told me that a reel mower will not work, but many have also stated how amazing my lawn looks in comparison to theirs with a rotary. Granted, I was mowing mine twice a week, and with 500m2 of lawn to mow, I eventually went back to rotary due to time restraints. I do, however, also have a reel mower of which I use after the rotary to give the lawn that crisp, sharp cut that a rotary will never achieve.

The way I see it, and to the dismay of many - a lawn is like a tree. You can train it to be small like a bonsai, or you can let it grow into something long. At the end of the day, the difference is simply in your desire and the effort you're willing to put in to get the result you wish to achieve, however, I've yet to come across a lawn I've never been able to get the desired result.