Re-Powering a lawnmower - worthwhile ?

[gromit]

Before I start, I'm not interested in changing to a battery operated lawnmower.

I have an old ride-on and use a smaller mower for the edges and a couple of small grass areas.
My trusty MTD mower has been going for 22 years and is now using oil and smoking worse than a 2-stroke. Piston rings and a few gaskets start to get expensive (Briggs & Stratton Sprint 375) and to be fair the motor is probably nearing the end of its life.
It's had minimal maintenance, a few oil changes over it's life, air cleaner cleaned once or twice and still on the original blade & sparkplug. Still starts & runs OK, just the smoke. The throttle lever broke some years back (plastic) so it's been run on fixed revs since.

The young bloke had a couple of mowers he was playing with plus I was given an alloy deck Flymo with the same Sprint motor. Got this one going after cleaning the carby but it also smokes.
Also have a Chonda (Chinese Honda) young bloke got off hard rubbish and a replacement motor also from the young bloke. After an engine swap and a carby clean I now have one that's working without smoke signals. Remarkably quiet but not great condition.

I can buy a Briggs & Stratton OHV replacement for the Sprint motor for about $220 delivered. I'd fit it to the alloy Flymo deck and probably get years of use.
I can also buy a new Sanli (Chonda) mower from Big W for $229.

I probably have some life from the Chonda I've repaired and I'm trying to make up my mind whether I should just buy a B&S motor and dump all the others.
Briggs & Stratton 3.75hp (550EX Series) Lawnmower Engine – Small Engine Warehouse Australia (https://www.smallenginewarehouse.com.au/collections/frontpage-collection/products/briggs-stratton-3-75hp-550ex-series-lawnmower-engine)



Colin

[ramblingboy42]

so your last one lasted 22yrs and you can get a new one for $220?

I wouldn't be quibbling, I'd get the new b&s for another $10/yr

[Homestar]

I bought a Sanli years ago when they first came out - probably around 8 or so years ago now and it still starts first or second pull every time and I’ve never done a thing to it other than change the oil every other year. I think I paid around $300 back then from a mower shop before big W and Bunnings started selling them but it’s probably the best value mower I’ve ever bought.

[Bigbjorn]

I bought a Sanli years ago when they first came out - probably around 8 or so years ago now and it still starts first or second pull every time and I’ve never done a thing to it other than change the oil every other year. I think I paid around $300 back then from a mower shop before big W and Bunnings started selling them but it’s probably the best value mower I’ve ever bought.

Why don't you just buy a new mower for not much more? I you are going to **** about swapping engines make sure you get one with a flat base plate on the crankcase not a corrugated one. Flat is made in USA at the Milwaukee plant. Corrugated is made in the celestial kingdom.

[theelms66]

this is why we have become the biggest waste country . everything is cheaper to replace than repair

[josh.huber]

If you go down the replacement line, keep an eye on gumtree. My next door neighbour sold a near new Honda for 300 bucks.. Wanted a quick sale. I'm not fussy on what things look like so second hand is the way for me.

[gromit]

I bought a Sanli years ago when they first came out - probably around 8 or so years ago now and it still starts first or second pull every time and I’ve never done a thing to it other than change the oil every other year. I think I paid around $300 back then from a mower shop before big W and Bunnings started selling them but it’s probably the best value mower I’ve ever bought.

Used the hard rubbish Sanli today without issue.
It's a 'Gardener's Choice' which might be K-mart ?? It's stood outside for a year or two and only when mine started smoking did I swap out the motor. The other Sanli motor the young bloke gave me had coil pack problems, once it got hot it died and refused to restart. Internet search came up with numerous Sanli coil pack problems, mower shop wanted $70 for a coil pack !! Couldn't find one online at the time.


Why don't you just buy a new mower for not much more? I you are going to **** about swapping engines make sure you get one with a flat base plate on the crankcase not a corrugated one. Flat is made in USA at the Milwaukee plant. Corrugated is made in the celestial kingdom.

The question was more do I take a punt with a Chinese copy of a Honda or buy a B&S motor ? Not a big job to change a motor, 3 bolts, fit the blade and the throttle cable. The unknown for me is the B&S OHV motor vs. the old sidevalve motors. Thanks for the heads up about the baseplates.


If you go down the replacement line, keep an eye on gumtree. My next door neighbour sold a near new Honda for 300 bucks.. Wanted a quick sale. I'm not fussy on what things look like so second hand is the way for me.

They turn up cheap at the local Trash & Treasure market but unfortunately it's closed for the time being.....
Most of the ones on Gumtree locally are from people who repair them for a living or near new prices being asked for old mowers.

The hard rubbish Sanli will do for the time being.


Colin

[superquag]

My first machines was a ROVER brand, all aluminium deck and with a properly proportioned handle which made one handed-about-face turning effortless - as quick and painless as it should be.
Engine was a Bang & Stop side-valve thing... Very VERY average in starting. Eventually.
Mercifully, it died after 15 or so years of boring if not faithful performance. Catcher was a solid black plastic moulded thing. Worked fine.
Replacement engines were unknown back then, at least economical ones... so #2 was a
- Chinese Bunnings brand , yellow and black abomination. Heavy, unbalanced to the point of being painful to use, and another disappointing engine, despite appearing to be OHV...


I've got an OHV B&S engine on the current (#3) piece of rubbish that's supposed to be a 'Professional' mower.
It's not.
Had trouble with the self-drive, belt fallling off and/or drive cable parting company from drive gearbox...and it trundles at a too-fast gallop... And the handle could be a tad longer and more securely mounted.

The rear catcher fabric is... a consumable item. Even being out in the sun as a domestic machine (it's touted as being "Industrial") is sufficient to visibly damage the material. Estimating a MAX 5 year life.

But, credit where it's due,,, engine is a willing , 3.75HP and starts first pull. Every time I find that it runs better overall on 95 or 98. Don't understand why, but it does.
Yes, if the deck broke I'd dump it and save the engine.
-- I'm not looking, you understand, but if I see another (road verge) ROVER alloy deck in good nick ...

Worst feature apart from weight, is poor 'balance', makes turning more difficult than it needs to be. A bit like driving a great car first, then stuck with Holdens thereafter...


My long-winded suggestion is to go for the GENUINE Briggs & Stratton engine replacement, if you reckon the wheels and 'balance' of your current one is otherwise satisfactory.
Or a real Honda... their engines all seem to run quieter, my personal problem with modern mowers. - I'd even go to a bigger $ HP engine if losing power in a great muffler was the price for peace !

[Tins]

Thanks for the link to the engine mob, Colin. $2160 for a new V-Twin for my ride on means that I'll be repairing the old one.....

[gromit]

The rear catcher fabric is... a consumable item. Even being out in the sun as a domestic machine (it's touted as being "Industrial") is sufficient to visibly damage the material. Estimating a MAX 5 year life.
The catcher on my MTD was a hard top & fabric bottom, has lasted 22 years no problem. Looking at some of the catchers on the latest Sanli mowers I doubt that they would last anywhere near that long. The MTD is double weave and heavy duty fabric.

-- I'm not looking, you understand, but if I see another (road verge) ROVER alloy deck in good nick ...
I have one here. The donor Sanli motor was fitted to it. The owner liked the Sanli but there was no height adjustment so he fitted it to the alloy Rover deck. I'll reserve it for you......

My long-winded suggestion is to go for the GENUINE Briggs & Stratton engine replacement, if you reckon the wheels and 'balance' of your current one is otherwise satisfactory.
Or a real Honda... their engines all seem to run quieter, my personal problem with modern mowers.
The Sanli, which is a Honda copy, is very quiet. Probably not up to the longevity of a Honda but who knows.....



The cheap Sanli from Big W has the net catcher, my hard rubbish Sanli has a traditional plastic catcher.

I've also noticed a motor that looks remarkably like a Sanli on other brand mowers (e.g. Victa). Maybe made under licence or they provide the motor ?

About Us — Sanli Lawn Products (https://www.sanli.com.au/about-us)


Decisions, decisions......maybe I'll try and wear out the hard rubbish mower....


Colin

[mick88]

Colin,
i had an old Wheel Horse ride on that we used for "rough mowing" around the place and it had a shagged 11 HP B&S on it, but structurally the mower body was in very good condition.
It was a very well built quality unit, so anything that did look like wearing out was easily repaired.
I purchased one of those 13 hp "Chonda" engines as a replacement for it.
It is absolutely brilliant, I only run it at a fast idle and it will charge through any amount of long grass/weeds, etc. and does it all on a miserly amount of fuel. It's a lecci start, but instead of having a battery in it i just use my jumper pack to fire it up and believe me, you can't stall it, it will never stop until the key is turned off.
The donk is about five years old now and still going as strong as the day i bought it.

Cheers, Mick.

[ATH]

I bought a B & S powered Rover Scott Bonnar new about 35 years ago and it starts practically first time every time due of course to my maintenance.....😉
It smokes a bit but not unduly so at least not enough to smoke the neighbours out and I thought about getting it reringed or whatever but I simply don’t trust the standard of workmanship from some of the repairers I’ve used for blade sharpening etc. in the past.
I caught one hammering the soft metal of the coupling on with a bare faced hammer instead of using a bit of wood to soften the blows.
I remonstrated with him in no uncertain terms and questioned his skills..... “I’m not a tradesman” was his answer!
Anyone could see that.
I like a reel mower as opposed to a slasher type, love the look of the lawn afterwards even if I have sweated heaps to get it like it. 😀
What to do? Maybe just think about it a while during our lockdown......
AlanH.

[gromit]

Well the Sanli (Chonda) is still going but every now and again it smokes like crazy then stops so I've been thinking about re-powering again.
Then the young bloke brought home another Sanli he found on hard rubbish. The return spring on the recoil starter has broken, starts & runs OK so looks like I'm re-powering the Sanli with another Sanli motor, just need to move the recoil starter mechanism !

Also collected, free, two old Stihl brushcutters. I'll see if they will work with some TLC. One looks almost identical to a McCulloch (actually Shindaiwa), I wonder if they made them for Stihl.


Colin

[350RRC]

Well the Sanli (Chonda) is still going but every now and again it smokes like crazy then stops so I've been thinking about re-powering again.
Then the young bloke brought home another Sanli he found on hard rubbish. The return spring on the recoil starter has broken, starts & runs OK so looks like I'm re-powering the Sanli with another Sanli motor, just need to move the recoil starter mechanism !

Also collected, free, two old Stihl brushcutters. I'll see if they will work with some TLC. One looks almost identical to a McCulloch (actually Shindaiwa), I wonder if they made them for Stihl.


Colin

I've had a sanli for over 10 years.

Only issues are the handle is weak where it used to fold (got bolts through it now) and has a tendency to accumulate water in the bottom of the carb, which is easily drained by undoing the little bolt at the bottom. Gets a splash of metho in the fuel to help prevent this as well.

Have had the recoil spring break, just take it apart and bend a new tang.

From memory there is also a larger spring inside that actually spins the motor using force generated by pulling the rope.

You really don't want this to uncoil. Real pita to repack. Have a spring clamp handy to hold it in place when you dismantle.

DL

[gromit]

I've had a sanli for over 10 years.

Only issues are the handle is weak where it used to fold (got bolts through it now) and has a tendency to accumulate water in the bottom of the carb, which is easily drained by undoing the little bolt at the bottom. Gets a splash of metho in the fuel to help prevent this as well.

Have had the recoil spring break, just take it apart and bend a new tang.

From memory there is also a larger spring inside that actually spins the motor using force generated by pulling the rope.

You really don't want this to uncoil. Real pita to repack. Have a spring clamp handy to hold it in place when you dismantle.

DL

Just had to move the recoil spring from the old to the 'new' Sanli ! I've bent a new tang in the past, recoiling the clockwork spring is 'fun'.
Decided to do the motor swap as I went to start the mower today and it wouldn't fire. Removed the plug and found it packed full of oily dirt, cleaned the plug and it ran but was very smokey.

There were a few minor differences between the two but it's now fitted.

I'm sure the young bloke will try and sell my old motor.


Colin

[350RRC]

Used mine today, was a bit dusty and it started running rich so the air cleaner will get blown out tomorrow.

It doesn't have the secondary spring in the recoil unit, I had it mixed up with one of my chainsaws.............. probably because everything I have that is pull start has cord from the stihl shop in it.

DL