View Full Version : Commercial LawnBoy 22260 problem

Double Cut
05-16-2007, 09:39 PM
Hello all and thanks in advance. Anyone had this happen?

I am running a commercial lawnboy and it does not seem to "rev" or "spool" up as much as it used to. When I get into a little taller grass (3") the mower seems to bog down to the point of stalling out (did not happen before). If I walk it reeeeaall slow it seems to pick up again. Is this a carb or jet problem?

I have:

Made sure fresh gas is in mower.
Checked fuel cap that it can breathe.
Cleaned out the filter.
Replaced the plug.
Checked under deck for grass and clogs.

Thanks, Marty

lawnboy dan
05-16-2007, 09:56 PM
if there are a lot of hrs on this lb the exaust ports could be clogged with carbon deposits. you will need to remove the muffler to look inside at the exaust port. also check to see if the govner vane is moving freely tru its travel range. lastly you can set the gov a little higher(this wont help if exaust is plugged) turn the white collor several clicks clockwise to increase rpm (its on the carb just under the white plastic gov vane. ) i am not called lawnboy dan for nothing

Double Cut
05-16-2007, 10:35 PM
Ahhh It has to be that. I have about 10hrs. on the mower. There has been a bit of exhaust build up on the front of the deck. My "associate" did the gas mixing. Can bad mixing of gas cause the excelerated deposits? How do I clean it out? Any damage done to mower?

Thanks, Marty

lawnboy dan
05-17-2007, 07:48 PM
if your hours are truely that low-i doubt that the exaust could be clogged. never trust someone else to mix your 2 cyc gas -ever! first try draining the gas in it and try a fresh batch you know is mixed at the correct ratio. 32/1 . get a can of lawnboy oil if possiable . while i have several of these duraforce engines- i havnt ever had to decarb them so i can tell you how to do it on this engine. this engine is very diff from other lawnboy desighns

Double Cut
05-17-2007, 10:26 PM
Thanks Dan, Before I had the mower the previous owner said he ran about 6 tanks of gas thru it. I do not know how that translates to time. There seems to be a bunch of "gunk" near the exhaust. I think he ran it with too much oil. The other lawnboys I have I do run the ashless recomended lawnboy oil. He might have used some other junk I have no idea. I will upload some pictures to show you tonight.



Double Cut
05-17-2007, 10:46 PM
Here are some pics. If you look past the muffler housing the entire muffler is coated with this oily dirt. It cleans right up with a quick wipe. I removed the gunk off the deck. I wonder why this happened? The previous owner may have a hand in it? But that fast? I know the mower has low hrs.


05-17-2007, 11:13 PM
DoubleCut ... I have a 22261, the same mower, but self-propelled. I will spare you all the history of the machine over the past couple of years, but some of it hasn't been pretty!

This machine gets run quite hard. Often, one tank of fuel per day isn't enough. Some days, nearly a tank, and a half, is run through. I think it will run about six straight hours on one tank of mixed fuel, maybe a bit more than six. So, if the previous owner ran six tanks of fuel, it may have about 35 hours behind it.

Double Cut
05-17-2007, 11:29 PM
Thanks for the input Roger. I will run this mower about 2hrs. a week. I do not cut full time. Please tell me the nasty nasty about the mower. I have heard good thigs about this model. I am sure there is more to tell.:cry:

Have you had this problem? errr anything like it?


05-18-2007, 12:51 AM
thirty five hours is nothing to a commercial mower. The pictures are nice, Thanks. It looks like a new machine to me. I would suggest you install a inline fuel shut off right away or the problem will persist with the oily buildup on the deck under the muffler. The needle and seat are leaking and the excess fuel is going through the engine, out the exhaust ports into the transfer tube which is like a p-trap, into the muffler and blown out the next day when you start the engine. Classic duraforce symptom. I don't know of very many that don't do this.

The best thing is the shut off. Its a pain to shut off and on but it will stop the oily crud.

The float could be heavy now also causing some of the issues. The main problems with duraforce engines in my Opinion are the carb farts you will be having.

I'd install a shut off run the carb dry and then refill and try it and see if maybe the float was stuck or something.


05-18-2007, 12:56 AM
You have to take the muffler off to expose the ports.

05-18-2007, 10:28 AM
Just throwing this out there.

I've had bad luck running Lawnboy Oil at 32:1 ratio. Lots of carboning up.

I run 50:1 major brand mix like I do on all my 2 cycle stuff. Haven't cleaned a muffler out in quite some time.

05-18-2007, 11:39 AM
I run 80 to 1 Amsoil synthetic in all my 2 stroke engines since 1979. No smoke and no problems.

lawnboy dan
05-18-2007, 06:48 PM
i agree you need to turn the fuel off after the days use is over . every duraforce i have seen has poor needle /float seating also install a inline fuel filter.

Double Cut
05-18-2007, 07:32 PM
Do you think any damage was done to the motor? I am thinking not since it is better to run with too much oil than not enough to damage the piston etc.

I was also told to take the muffler off and heat it with a acetalene torch REAL Hot to burn of the gunk. IS cleaning the port just a scrape off the gunk procedure?


lawnboy dan
05-18-2007, 09:41 PM
good advice -burning the muff but all you need is a butane torch. yes you just scrape the carbon out of the exaust port but be carefull not to scratch the piston -best to use a wooden object of some sort. too much oil wont hurt a engine -just make it run worse than it should. synth oil will burn cleaner and help avoid carbon build up . try the sthil ultra hp oil-great stuff. i would mix it at 40/1 instead of the lawnboy oil at 32/1. i think 32/1 is too rich a mix when using synthetic oil

Double Cut
05-18-2007, 09:48 PM
Thanks Dan. Looks like a weekend project. It looks like I have to take a bunch of stuff off to get to the muffler. Looks like a 6 pack project! :drinkup:


lawnboy dan
05-19-2007, 08:39 AM
agreed! they made this muff sys way to complex on theis engine desighn.