Two stroke carnage.

[bwalker]

Awhile back I picked up a nearly new appearing Toro Snow Commander with a 7hp Rtek motor, which is a piston port version of a Lawnboy Duraforce.
When I got it home it was surging pretty bad which is a very common problem. So I put a bigger main jet in it and adjusted the Governor arm and it ran like a top.
I then laid it up and put it in the shed for a spare as I already have an identical but very high hour twin to it. The high hour machine recently lost spark so I pulled the spare and have used it once when this happened.

 

[bwalker]

These engines have an aluminum rod and a bearing setup that's very sensitive to max rpm and oil quantity.
I'm guessing the previous owner ran it for some time with it surging and the rod finally gave up the ghost on me.
The piston and cylinder both where in good shape and obviously had low hours.
Although the piston crown did have ash build up so the previous owner wasn't using the right type oil.

 

[bwalker]

Piece of the bearing shell hit me in the foot when it blew. These motors use roller over a silver coated shell type bearing.

 

[heimannm]

Foot O.K.?

 

[jellyroll]

Duraforce engines are not that strong to begin with.

 

[bwalker]

Foot O.K.?

Yes, barely felt it.

 

[bwalker]

Duraforce engines are not that strong to begin with.

The crank shaft itself is probably double the size it needs to be, but the rod is too small and made out of aluminum, which is that motors weakest link. If they had a steel rod and regular roller bearings they would probably last as well as any Lawnboy.
The other problem is the carb is plastic and the governer is a cheaply made piece of crap. Most of these machines either over/under rev or surge. Almost all of them need a richer main jet. It's like they were set up to fail from the get go.

 

[flatsfisher]

I bought this new in 2004. best running and cutting and most powerful single cylinder mower I've ever had. still runs great but now I have too much grass and use a zero-turn mower.

 

[bwalker]

I bought this new in 2004. best running and cutting and most powerful single cylinder mower I've ever had. still runs great but now I have too much grass and use a zero-turn mower.

View attachment 1153815View attachment 1153816

I bought a LB Commercial around 03. The motor sucked a reed though it a few years back so I scrapped it. I replaced it with a Honda.
I do have a soft spot for a Lawnboy M series, which had a Suzuki motor. If I come accross a mint one I'd buy it.

 

[Jasonrkba]

I traded my 6.5 duraforce lawn boy for a mac 10-10S a few years ago. I bet that mower is still going.

 

[jellyroll]

I bought a LB Commercial around 03. The motor sucked a reed though it a few years back so I scrapped it. I replaced it with a Honda.
I do have a soft spot for a Lawnboy M series, which had a Suzuki motor. If I come accross a mint one I'd buy it.

How about a restored commercial M series. I use this site when i need a lawn boy.
https://lawnboyrescue.ecrater.com/c/1837799/lawn-boy-commercial-mowers

 

[flatsfisher]

I bought a LB Commercial around 03. The motor sucked a reed though it a few years back so I scrapped it. I replaced it with a Honda.
I do have a soft spot for a Lawnboy M series, which had a Suzuki motor. If I come accross a mint one I'd buy it.

Toro made a 2 stroke mower with a Suzuki engine that was pretty popular. was only 5hp or something though.

 

[Sidecarflip]

Used to have a 'Flymow' that was a neat mower with no wheels. Great for mowing creek banks. Had a Tecumseh 2 stroke shitte engine however but then all Tecumseh motors were basically shitte. Had a Lawnboy as well but liked the 'Flymow' better.

 

[bwalker]

Toro made a 2 stroke mower with a Suzuki engine that was pretty popular. was only 5hp or something though.

Yes, that's the same motor as in the LB M series.

 

[ZeroJunk]

Not sure about the difference between Silver and Gold in this case, but I have a 10326 that I have worn the gear drives out twice, on the third set of rear tires, and it runs fine.
That is 50 to1, Sabre now, but HP Ultra for a good while.
I suspect I will run out of being able to patch the deck before the engine gives up.

So, you can have a defect in anything.

 

[bwalker]

Not sure about the difference between Silver and Gold in this case, but I have a 10326 that I have worn the gear drives out twice, on the third set of rear tires, and it runs fine.
That is 50 to1, Sabre now, but HP Ultra for a good while.
I suspect I will run out of being able to patch the deck before the engine gives up.

So, you can have a defect in anything.

I don't recognize that model number. 6.5 hp Duraforce?

 

[flatsfisher]

Not sure about the difference between Silver and Gold in this case, but I have a 10326 that I have worn the gear drives out twice, on the third set of rear tires, and it runs fine.
That is 50 to1, Sabre now, but HP Ultra for a good while.
I suspect I will run out of being able to patch the deck before the engine gives up.

So, you can have a defect in anything.

on the duraforce, gold had either the 3 spd or easy-stride system and a cast aluminum deck, whereas the silver series had a 1 speed and pressed steel deck. maybe also some color differences.

 

[ZeroJunk]

I don't recognize that model number. 6.5 hp Duraforce?

10323 Senior moment.

 

[Tony Mayhew]

on the duraforce, gold had either the 3 spd or easy-stride system and a cast aluminum deck, whereas the silver series had a 1 speed and pressed steel deck. maybe also some color differences.

I just acquired one of those commercial lawnboys this past summer for thirty bucks non running. Which is usually the way I end up with so much cool stuff without paying the absorbent price for it brand new! The older ones look better than the newer ones I think? I have a back yard full of vintage lawnmowers and a shed full of vintage chainsaws! I bet all my neighbors think I'm crazy because I mow my grass with a different lawnmower each week during the summer months.