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Design improvements - not!

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Design improvements - not!

Old 29th Jul 2020, 21:11
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Design improvements - not!

My twenty five year old rotary lawn mower has a manual choke for starting and a manual throttle to control the engine and travel speed. When I need to empty the grass collector I let go of the drive clutch bar and the mower stops moving but the engine continues to run. I throttle it down to a nice slow tickover, empty the grass cuttings, replace the grass collector, throttle up again and off I go. If it strikes a root or other obstacle with the cutting blade it has a slipping drive to the blade which slips momentarily and then carries on as normal.

My Mother has the latest incarnation of the same mower by the same manufacturer. It now features a mechanism which requires the operator to keep a bar pulled in to keep the engine running meaning when you break off to empty the grass collector it stops and needs to be pull started. It also features an automatic choke and a fixed throttle which together conspire to make it virtually impossible to restart if you take more than a few seconds to empty the cuttings. Just what my Mother, in her eighties needs - not. The fixed speed is a little quick for my Mother but a little slow for me. Another design improvement has replaced the slipping blade drive (a dished spring washer squeezing the blade against a flat hub) with a drive hub featuring two pegs which engage with matching holes in the blade. If it strikes a tree root or other obstacle it sheers off the two pegs and the blade swings freely about the centre bolt. You know when this has happened as, with the blade swinging freely, there is not enough flywheel effect for the engine to run even when the auto choke gets the fuel air mixture right. Joy oh joy, the broken drive pegs are part of a 16 replacement part requiring an hour of workshop time to fit. Again, not what a lady in her eighties needs.

If it aint broke don't f**k it up.

Rans6...................
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Old 29th Jul 2020, 21:21
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Our last mower was like this, a complete PITA having to restart it all the time, and having to keep the bar pulled in all the time to keep it running. I put up with it for about an hour, then it had a serious visit to my workshop, where all the "safety" crap got taken off and bypassed, turning it back into a proper mower once more.

We now have a smaller lawn, and use a Makita cordless mower, that runs from two of the same 18V lithium battery packs that my other Makita power tools use. It's surprisingly powerful, and very light and easy to use. The only thing we have to watch is to make sure we never let the grass get too long, as it doesn't have as much grunt as a petrol mower.
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Old 29th Jul 2020, 21:34
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I’ve been a professional cheapskate all my life, especially in regard to buying second hand lawn mowers. But.....(in my mid seventies) ..reluctantly, I’ve just bought a brand new Cobra 4340 40v battery mower c250.
I’m ‘sold’ on it, it’s absolutely everything I want in a fairly ordinary lawn mower. No more cutting thru’ the cable and it collects the grass OK.
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Old 29th Jul 2020, 22:27
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My "Mountfield" petrol mower has the same arrangement i.e. a thin metal cross bar must be held against the main handle to complete the ignition circuit. I too found it a nuisance to have to keep restarting the engine. However, after suitable use of adjustable tie wraps it no longer springs back and has to be pulled very slightly away from the bar to stop the engine.

The other annoying thing I found only recently when doing some 10 year major mechanical maintenance - due to a factory build error (a circlip holding a drive pin in the wheel was missed off the end of its axle) it has only ever driven one rear wheel, not both. Now remedied, it has made it much easier to use!
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Old 29th Jul 2020, 23:30
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I have a large Hayter, (56), about 1 year old.
I just tie up the bar. Undo it when finished.
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Old 30th Jul 2020, 00:36
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If it aint broke don't f**k it up.
Why do they have to keep changing everything ( yes I know, planned obsolesence - barstewards )

Doubtless the operating bar, to ensure that the engine stops when emptying, was the result of some stupid Health and Safety nonsense. Whatever happened to commonsense ?
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Old 30th Jul 2020, 02:46
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I had a neighbor friend who managed to lose part of his foot to a rotary mower when we were teenagers. While he wasn't exactly the brightest bulb on the tree, it's not that hard to do - especially for teens who are rather fond of doing dumb stuff.
If you really hate having to restart the mower, you can get one with a "blade brake safety" - basically when you let go of the lever it stops the blade in a fraction of a second - but the engine keeps running. I have that on my Honda mower - costs a bit extra but I like it.
That being said, when I replace this mower, I expect I'll get a battery powered one - they've gotten much better of the last few years.
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Old 30th Jul 2020, 07:03
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When I mail ordered one of these with american designed, chinese made 4 stroke engine, 8 years ago the safety bar was bad surprise indeed. My first impulse was to get the cable ties as well. However when warm, I found the engine to start on the first casual pull at the second click just like a good old lycontisaurus. It has a throttle lever and auto choke, which was never a problem for me. Priming by a little ball pump. If I get it right it does cold start at first pull. As I tend to prime rather less, often I need to redo an pull a second time - but that's it.
I did not manage to sheer the pins from the blade drive of in all that years.
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Old 30th Jul 2020, 09:02
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Originally Posted by Ancient Observer View Post
I have a large Hayter, (56), about 1 year old.
I just tie up the bar. Undo it when finished.
I have a Hayter with the bar.
I use a cheap clamp which can be released instantly if I need to cut the engine.
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Old 30th Jul 2020, 11:27
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I have a rotary Torro (and yes it's Rosso ), when you remove the grass bag, a magnetic switch is closed, earthing the ignition circuit preventing the removal of the bag with the engine running.

I believe its called elf n' safety.

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Old 30th Jul 2020, 11:31
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Originally Posted by rans6andrew View Post
My twenty five year old rotary lawn mower has a manual choke for starting and a manual throttle to control the engine and travel speed. When I need to empty the grass collector I let go of the drive clutch bar and the mower stops moving but the engine continues to run. I throttle it down to a nice slow tickover, empty the grass cuttings, replace the grass collector, throttle up again and off I go. If it strikes a root or other obstacle with the cutting blade it has a slipping drive to the blade which slips momentarily and then carries on as normal.

My Mother has the latest incarnation of the same mower by the same manufacturer. It now features a mechanism which requires the operator to keep a bar pulled in to keep the engine running meaning when you break off to empty the grass collector it stops and needs to be pull started. It also features an automatic choke and a fixed throttle which together conspire to make it virtually impossible to restart if you take more than a few seconds to empty the cuttings. Just what my Mother, in her eighties needs - not. The fixed speed is a little quick for my Mother but a little slow for me. Another design improvement has replaced the slipping blade drive (a dished spring washer squeezing the blade against a flat hub) with a drive hub featuring two pegs which engage with matching holes in the blade. If it strikes a tree root or other obstacle it sheers off the two pegs and the blade swings freely about the centre bolt. You know when this has happened as, with the blade swinging freely, there is not enough flywheel effect for the engine to run even when the auto choke gets the fuel air mixture right. Joy oh joy, the broken drive pegs are part of a 16 replacement part requiring an hour of workshop time to fit. Again, not what a lady in her eighties needs.

If it aint broke don't f**k it up.

Rans6...................
May I suggest one with a battery starter and variable speed? They do exist, I had one.
Per
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Old 30th Jul 2020, 12:54
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Rans, be a good son and swap l/mowers with your Mum....
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Old 30th Jul 2020, 13:30
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I have just had to get imported some spare parts to fix my Briggs & Stratton powered mower that was working fine until 5 minutes after being serviced in the UK before export! I too have the stop bar that needs to be held against the controlling frame of the machine. I considered just tying it up so the motor would keep running but decided against it as it is very easy when taking off the grass collector to put your hand in and pull out more grass cuttings. That has all the trappings of losing fingers?

The service engineer in UK disconnected the fast/slow throttle saying that it served no purpose at all. When I fitted these new parts just a few weeks ago, (the problem was that the engine was running very rich, was reving on it's own, and fouled the sparkplug after 10 minutes) I found that there was no physical connection to the carb from the throttle cable. Eventually thanks to google and youtube I found that the engine speed/walking speed can be adjusted by bending a piece of metal therefore altering a spring tension to the throttle butterfly. Incidendly the reason the engine was running rich in the first place was due to a gasket in the carb having been destroyed by modern petrol! It now has a usable life of only 2 years! And now that they are introducing this new petrol for cars I can predict very similar problems in future? I am convinced the world is rotating backwards?
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Old 30th Jul 2020, 14:31
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One of my abiding memories is of my Dad trying to start the mower. And swearing a lot in the process.

Now that lithium batteries are a thing - much lighter than the equivalent lead acid, and rechargeable in about 30 mins - electric mowers are extremely practical. No oil or fuel required to be kept in containers. Instant start with a switch. No farting about with a choke etc. Less need to use ear defenders, (although I do anyway). No engine servicing. The blade stops when you release the switch, so by the time you are taking the grass collector off it is safe to stick your hand in. Having no oil or fuel means you can tip the whole mower on its side to clear out grass stuck underneath - without the engine fluids leaking out everywhere. They are just as powerful as petrol mowers, and the fact they run out of electricity after 30-40 minutes is not a problem at all: simply put the battery on charge and go and have a cup of tea.

The range of mowers and other garden machinery made by Ego is very well made and works very well.

The problem with health and safety devices such as the 'safety' bar on a petrol mower is that they can actually make it more dangerous, since people override them, and then cannot stop them quickly in an emergency.

Thread creep:
Health and safety. Yesterday I was prevented from jogging along a stretch of a canal by a chap who was trimming the hedges. This guy would not let me pass and as well as a full orange head to toe hi-vis suit, he was wearing a life jacket - I kid you not. A life jacket for trimming hedges along a canal towpath. Yes, he could potentially have fallen in if he tripped, but whatever happened to being careful and using common sense?

Last edited by Uplinker; 30th Jul 2020 at 14:43.
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Old 30th Jul 2020, 14:53
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I have an electric mower with the dreaded safety bar and advancing arthritis in fingers means pain sets in holding the thing back. Ah, I thought, tie the bar back and away we go. No, they have though of that and there is a button to be pressed when pulling the bar, and the bar has to be released to set it and allow the motor to start. Have given up and now pay a gardening firm to mow.
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Old 30th Jul 2020, 16:20
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When I was younger, I could mow our hillside lawn with a push mower in the time it took next door to start his motor mower.
Not sure if the motor actually reduced his total effort overall!
Battery mower for me now.
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Old 31st Jul 2020, 00:09
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I agree that 'elf 'n safety often seems to have gone too far but years ago my late uncle slipped on some sloping grass while cutting it using a rotary mower. His foot went under the mower and lopped off his big toe. Had he had a modern mower as he fell and let go of the handle the blade would have stopped. According to ROSPA accidents with mowers run at 6,500 per year.
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Old 31st Jul 2020, 00:51
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I fondly? remember having to replace a shear pin on an outboard motor's prop - underwater.
The owner only had two pins and I of course, dropped the first one while down there trying to get it in.
It was a nice slate grey that blended in with the lake bottom perfectly.
Got the last one in so the owner could go fishing.
He had lost both legs in the war. Nice man. Nicer daughter.
Bet they still use shear pins.
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Old 31st Jul 2020, 02:35
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So would we describe said idling mower while emptying catcher as hot emptying...?!
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Old 31st Jul 2020, 11:58
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47 year old Victa two stroke 160cc lawnmower, redid the piston rings myself last year and now left with a rattling noise that I can't trace (I think I got most of the broken old rings out of the crank case). But it starts second go religiously and cuts grass like new (almost), those stainless steel blades could do with a replacement - if I can find where I put the new ones.

The grass catcher attachment has a metal flap that closes when the catcher is removed. No issues whatsoever with needing to shut it down, just put the throttle into idle, lift the flap which locks the grass catcher in position, pull out the grass catcher and drop the spring loaded flap to close the grass feed. Simples.

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