Suzuki 2 stroke beater

[jp1961]

My 8481AE has the F engine but with the metal Walbro carb. How does the metal carb compare to the plastic ones commonly found on F engines? Any increase in power output or no?

Jeff

 

[Dixieboy]

The Walbro carb did add a little power but not much. The power increase was more from mixture control. It added adjustable throttle, choke to eliminate primer, better fuel mixture thru rpm range, more consistent carb settings, etc. The engine would run cleaner than with the plastic carb. But it had its problems , the throttle cable/choke settings were very had to set right and keep that way. The alignment of the air filter box is critical to setting the cable. If the alignment of the cable air filter box wasn't right then the choke would not completely close making a cold start almost impossible. We even added a primer to some of the models because of the problem so a user could make the cold start.

 

[javjacob]

Lawnboy F-engines typically put out about 4 hp, some time a little more. The different configurations effected power like carb, muffler, muffler plate, how the ports were machined in the block, air filter, etc. I was referring to the recoil starter on the top of the lawnboys and Toro/Suzuki. Previous f-engines and older lawnboys had the old side mount starter. I hate the side mount, I adapted a Suzuki starter to a f-engine in about 1986 and then we developed it for the f-engine lawnboy. No kidding.

Did you work for Lawn Boy? I actually like the side mounted starter. Its easy to remove the entire assembly with 1 bolt and replacing the pull rope and spring are simple. I also like how the rope routes behind the motor and up the push handle so its out of the way. The top recoil has the rope exposed above the motor and they get caught mowing under trees and shrubs ect.

I have 2 Lawn Boys with the side mounted starter and 5 with the top mounted starter. 3 of the top mount starters are F series and 2 are Duraforces. The ones I hate are the Duraforce set up because the shroud cover is one solid piece with the recoil mounted under it. If you have to remove the shroud cover you cant just take it off and set it aside. You have to just leave it hanging on the pull rope which is a PITA.

My only other complaints about the Duraforce is how they mounted the coil on the cylinder head and the air cleaner is a PITA to get to at the back of the deck.
My only complaint about the F series (and D series and C series) is the cylinder and head are one solid piece so they cant be re sleeved or plated ect.

 

[javjacob]

My 8481AE has the F engine but with the metal Walbro carb. How does the metal carb compare to the plastic ones commonly found on F engines? Any increase in power output or no?

Jeff

There were more than one plastic carb for the F series. They used plastic carbs then went to the Walbro carbs then went back to plastic carbs. The HP rating went from 3.5HP on the early models up to 5HP on the later models. The 5HP models had plastic carbs. I think the Walbro carbed F series were only rated at 4HP and 4.5HP.
With all that said I question whether any of them actually had any difference in power.

 

[Dixieboy]

I did work for Lawnboy for about 3 1/2 years from 1984 to 1988 when headquarters were in Memphis, Tn. I was an engineer in the Advance Products group(only three of us in the group). I ran a lot of F-engines on the dyno. It was great fun. I didn't make the move to Wisconsin in 1988 and was laid off as were many others. I did develop the top mount starter for the F engine and all the mounting components. The F engine was pretty simple and inexpensive to manufacture, thus no removable head. As you know the entire block is only two pieces. I have five running lawnboys , all but one f-engine the other is a D. I have never even looked a Duraforce over , they came after the company was no longer a division of OMC. When I saw the first Lawnboy with Tecumseh I thought "there goes the neighborhood" and the two cycle roots. EPA was killing the two stroke. And just me but I never thought the side mount starter gave you the ratio to crank the engine very good. We did make little guide lopes to mount on the handle anywhere you may want to route the pull rope differently.

 

[javjacob]

That is really cool. I do agree the F series is as simple of an engine anyone has ever made and that's what I like most about them. They are so easy to work on. They also make good power and are as durable and reliable as an engine can get. There is nothing not to like.

 

[Two-Stroke]

I did work for Lawnboy for about 3 1/2 years from 1984 to 1988 when headquarters were in Memphis, Tn. I was an engineer in the Advance Products group(only three of us in the group). I ran a lot of F-engines on the dyno. It was great fun. I didn't make the move to Wisconsin in 1988 and was laid off as were many others. I did develop the top mount starter for the F engine and all the mounting components. The F engine was pretty simple and inexpensive to manufacture, thus no removable head. As you know the entire block is only two pieces. I have five running lawnboys , all but one f-engine the other is a D. I have never even looked a Duraforce over , they came after the company was no longer a division of OMC. When I saw the first Lawnboy with Tecumseh I thought "there goes the neighborhood" and the two cycle roots. EPA was killing the two stroke. And just me but I never thought the side mount starter gave you the ratio to crank the engine very good. We did make little guide lopes to mount on the handle anywhere you may want to route the pull rope differently.

Couldn't agree more. :thumbsup: