According to the LB Parts Finder, it is a 1980 D411 engine. Normal LB oil mix for this is 32:1. In those days, LB said to use twice the amount of oil IF LB oil was not used. (16:1) While I have used the oil you listed "in the old days" I do not recommend doing so. Much more carbon build up in cylinder and exhaust ports besides the excess smoke.

Hourse power would be 4 - 4.5 hp., as I recall.

Walt Conner

I would be interested in how you set up this engine to run in the horizontal position.
Thanks,
Bill

You may want to confirm this with a lawnboy expert, but I understand the engine is configured to run in one vertical position. If you switch to horizontal don't you run the risk of inadequate lubrication?

I'm not so sure about lubrication issues but I'd like to know how the carburator is installed.
I certainlly would not run NON-DETERGENT 30 weight in it at any ratio, unless someone else knows something I don't.

Sounds like a neat project though. I'd love to hear more from enginenigma.

Maybe he means he built some kind of pully system and it still runs in the vertical position? Who knows.

I would not run regular non detergent oil in any 2 stroke. I gave a 74 D-600 to my cousin and he had it for about 2 years and he said that it was loosing power and he does not know why. The exhaust ports were cloged and the piston had some bad scoring pluss the rings were gummed up. I would not run regular automotive oils in a 2 stroke.

'If you switch to horizontal don't you run the risk of inadequate lubrication?'

With a 2-cycle? No.

I know of at least one 2 cycle motor designed for horizontal use that when used in a vertical configuration had bearing failures. I don't have the technical information about the mower engine in question to be able to say for sure that a change in the alignment will or will not cause lubrication problems. It would be an interesting question to pose to someone with a technical background that includes knowlege of that motor.

No problem with lubrication as Saxman said but I would like to know how you mounted, re-mounted, the carbutator.

Walt Conner

Sorry I took so long to get back to this forum. I simply went to HomeDepot and purchased copper pipe that mated quit nicely with "O" ring in intake manifold. Epoxied copper pipe into short length of PVC pipe with another "O" ring. I then fashioned a flange to accept a Tillotson diaphragm carburetor.
After I was happy with design, I fiberglassed the whole shootin' match and now have pretty much solid intake pipe. This engine will now run in any position I choose. There are no lubrication issues given the fact that oil is mixed with fuel. In 30 plus years of expierence with 2 cycle engines, I have never witnessed or even heard of bearing failure due to changing crank shaft orientation. Biggest problem now is how to keep from smoking the tires. This engine seems to have high low end torque.

I can tell you probably had experience with 2-cycle go kart engines in the past. I smoked my neighbors out with 16:1 ratios of Shell X-100 and Texaco Havoline for years. Nasty stuff in a 2-cycle engine. We ran what we had though. Why not use a synthetic 2-cycle oil for trouble free operation and zero lubrication issues. Amsoil and Mobil-1, are good among a long list of others.
As far as the use on a go-kart is concerned the engine position will not matter. Post a photo of your hybrid Lawn-Boy go-kart.

How can post photo?

Lawn-Boy powered Go-Kart

Here is a link that might be useful: Yahoo Photo

For anyone that might be curious...I gave up on using 8601 "D" engine converted to horizontal shaft for use on gokart in favor of 680543 "F" engine. More powerful, smoother running, needle bearings all around and easier to get parts for. This thing is FAST and fun and runs better than that old Clinton Panther. For a look-see, click on Optional link URL:

Here is a link that might be useful: Lawn-Boy gokart video 2

Thats cool! I've never seen a two cycle go cart before.

Can you post some pics of it other than yahoo? Some of us are not yahoo members so we can't see it in pics.

Thanks for sharing.

Neal

That was pretty kool! Must have taken some time to engineer that setup.

Public pics available.

Here is a link that might be useful: lawn-boy

Check out 'World's Fastest Lawn-Boy on YOUTUBE.

Here is a link that might be useful: YOUTUBE

Hi enginenigma.

Awesome machine!

What's your best E/T in the quarter mile?

Are you using 91 octane fuel and 2-cycle engine fully synthetic oil?

Go Speed Racer Go!

Good day.

'Thats cool! I've never seen a two cycle go cart before'

All racing Karts were 2-cycle in the past although there are now 4-cycle classes. You need to see a dual-engine 2-cycle Kart ripping by at 9000 RPM and 80 MPH.

Enigma - you seem to have geared it high to take advantage of the low-speed torque of the engine - very wise. I like the LB green/red paint scheme, too. I did notice on the video that it was '4-cycling' a lot which usually indicates an over-rich mixture, although I didn't notice excessive smoke.

Hi enginenigma.

Are there any future performance upgrades for the "World's Fastest Lawn-Boy"?

Are you going to build a LawnBoy 2-cycle Duraforce engine powered go-kart?

Please keep us updated.
Thanks.

Good day.

Hello friends:
Not all that awesome @ just over 40 mph, but a lot more fun(and half the weight) than the Clinton Panther I used to run as a kid. I use regular gas and Honda HP2 HI-Performance racing oil @ 32:1. Engine no longer runs rich. Carb used in video was a Walbro WG-8-1 (diaphragm). It does not have a high speed adjustment and was designed to run rich at wide open throttle. I switched over to a Walbro WGA-10-1 which is fully adjustable after removing limiter caps on needles.
It used to be that most gokarts were 2 cycle. Clinton, West Bend, and Power Products dominated the market.
We used to mix our fuel at 16:1 using non detergent SAE 30 oil per manufacturers specs. They smoked like a bear and emitted an odor that has to be experienced to be appreciated. I really miss those days. Using the Lawn-Boy engine brought back some of those memories. For those of you who have only experienced 4 cycle engines, you don't know what you are missing. It's really sad to witness the end of the 2 cycle engine thanks to the likes of Al Gore and all.
Dura Force will be next if I can find one at a reasonable price (running or not). Preferably free.
Stay tuned as this is a work in progress.

Hello all.

Hi enginenigma.

Thanks for the 2-cycle tech info and update on the "World's Fastest Lawn-Boy".

Great video too!

Good day.

DuraForce on it's way. Fifty bucks off Ebay. Much easier to soup up. Horsepower jump is just what is needed!!!

Hello all.

Hi enginenigma.

A LawnBoy 2-cycle Duraforce engine powered go-kart?

Widow maker for sure.

Go for it!!

Good day.

Hello all.

Hi enginenigma. What is the latest update on The World's Fastest Lawn-Boy Duraforce powered Gokart?

Good day.

Got side tracked by another project, a Briggs & Stratton 2 cycle powered gokart from a Toro snowblower.
DuraForce should be ready soon.

Here is a link that might be useful: Briggs & Stratton 2 cycle

Hello all.

Hi enginenigma. Thanks for the update and the new action video.

Great job on the Briggs & Stratton 2 cycle powered gokart project.

Looks like the Briggs & Stratton 2 cycle engine powered gokart has some git up and go!

Are you using an "expansion chamber" exhaust system with the Briggs & Stratton 2 cycle engine?

I think the new LawnBoy snowblower/throwers still have the DuraForce Snow(R-Tek piston ported 2 cycle engines).

I'm not sure which is more powerful, the LawnBoy DuraForce 2 cycle engine or the DuraForce Snow(R-Tek piston ported 2 cycle engine).

Go Speed Racer Go!

Good day.

Toro SB engine-Isnt that a Tecumseh?

I don't use expansion chamber. I use an aftermarket glass filled VW exhaust tip which has a slight megaphone shape yielding a gain of 2-3 mph over stock muffler.
The Lawn-Boy and Toro throwers do use the R*Tek/DuraForce piston ported Briggs engine. The Briggs engine I use in video is for Toro high end thrower and is slightly more HP than Lawn-Boy's high end machine. Increased power in Toro thrower engine due to an additional bypass port. Both are Briggs engines and look identical externally. Pistons are NOT interchangeable.
The Lawn-Boy DuraForce MOWERS are basically the same engine but are reed inducted and (were) manufactured by Toro/Lawn-Boy.

World's Fastest Lawn-Boy just got faster.
As promised...Lawn-Boy DuraForce powered GoKart.
This is the first time a single wheel drive kart frightened me. Traction (or the lack of it) becoming a problem.

Here is a link that might be useful: Lawn-Boy DuraForce Powered GoKart

Hello all.

Hi enginenigma.

The Lawn-Boy DuraForce Powered GoKart is ready to rumble and begging to be "opened up" a longer runway.

What's up with the traction problems?

What DuraForce engine RPM "air vane" adjustment have you made?

You won't be cutting lawn grass at 3200 RPM with this DuraForce :)

Please find a longer test track and let that DuraForce Powered GoKart roll !!

Awesome machine and action video.

Great job on the World's Fastest Lawn-Boy!

You are the man enginenigma.

Good day.

"ready to rumble and begging to be "opened up" a longer runway"

Not an option at this time but working on it.

"What's up with the traction problems?"

Kart is clearly overpowered and have to 'feather' throttle when tire loses grip when coming out of sharp turns. Wish I had a live axle.

"What DuraForce engine RPM "air vane" adjustment have you made?"

No governor, therefore no 'air vane' adjustment.
I can only guess at RPM. 6k? 7K? I just don't know.
Compression ratio has been increased by removing head gasket and replacing with Loctite #515 flange sealant. No clearance issues.
Sound this thing makes has to be witnessed in person to be appreciated.

World's First Lawn-Boy (DuraForce) Powered Mini Bike

Here is a link that might be useful: World's First Lawn-Boy (DuraForce) Powered Mini Bike

Twin DuraForce power on the way.

Here is a link that might be useful: Twin Lawn-Boy powered GoKart

Hello all.

Hi enginenigma.

Jumping Jimmy DeCricket!!

You are the man with the plan enginenigma.

Good day.

Seeing these toys reminds me of the old McCulloch MC-9 I had as a kid on a go-kart and later on a minibike frame! I still have the engine, but need a carb kit and a clutch for it, but these are practically impossible to find. How did you make the clutch fit that tapered shaft? I never would have thought about using a LB engine, but it looks like a pretty sweet ride! If I ever get the old MC-9 going, we oughtta get together and race em! I used to love smokin' those lil Briggs and Tecumseh's back in the early and mid '70's!

I am a huge fan of this brand of mowers. Used them for over 30 yrs and they have been a staple in our family. I do however have two questions re: repair that I have never done and hoped that someone could help me.

1) I have a 7086 that needs the recoil assy replaced. I can't figure out how to get it off! Also, can the spring be reused? If so, how would I do that?

2) I have a 10550 that I have stripped of all the bells and whistles (self-propel, speed controls, etc). They created too many problems. As a result, my starter cord is hanging out of the engine about 3 feet. I cut it and reattached the handle. I can start it, but it only has 12"-18" in length. How can I add more string. Also, can I attach a vintage carb. to this model that has the speed control just above the air filter. You know, the green ones with the white lever.

I would appreciate any solutions or advice!

Re a carb swap; I hae been thinking about the same thing on my10323.I have a carb from a s21bsn that is a nice walbro metal carb with cable throttle and choke control.I've done this already on a 7271 AE that had a plastic carb that wouldn't run smooth. The swap was easy.I had to mount the throttle on the handle but runs great. On my 10323, th Walbro throttle cable needs to be attached on the opposite side.Another problem is that the carb hole pattern is wider than the lawn boy pattern they have always used. I plan to open up the existing holes. It should work ok.

bogman and afatone:
Please refrain from hijacking this dedicated/running thread.
Thanx

Calm down Enginenigma.This site often has wide ranging discussions about motors. This thread involved Lawn Boy motors and Afatone jumped in with some questions.No big deal, besides this a LAWN MOWER site not go carts.

"No big deal, besides this a LAWN MOWER site not go carts."

No, this is a Gardening site. Mowers just take up a small forum in it.

Well said, Orangedotfever. Case closed.

Sobeit.
There is such a thing as netiquette.
I suggest you read up on it.
I have yet to hijack or post anything off topic in your threads (or anybody elses for that matter).
I started this thread for those interested in using their L-B's for something other than what they were designed for and to show what is possible with our favorite engines/mowers.
Yup...case closed.
Thanx to everyone else for kudos received. It was/is appreciated.
I will be posting updates shortly elsewhere.

You have a point there EE. Let's put this to bed.

I have absolutely no problem with this thread as it was started and as it continued. It is entertaining and unique. Being a Lawnboy engine, it fits here just fine. Let's quit being so thin skinned shall we?

Sounds like a cool project

Here is a link that might be useful: My Mower Forum