• Landscape Lighting Design: Bright Ideas
    With outdoor spaces more popular than ever, lighting these landscapes may be your next opportunity. Click here to learn more.

starting Lawn-boy problems

calhoontuna

LawnSite Member
Location
Sussex WI
Have an M-Series Lawn-boy that I am having trouble starting. Two stroke.

When I pull the cord either nothing happens or the thing backfires (w/ choke closed).

Before this, I replaced the magnito/spark plug wire because the spark plug wire had gone bad. The mower had been getting progressively harder to start all Summer so perhaps my problems were more then just a bad magnito.

Used a business card to gap the magnito from the flywheel and it seems to be working right because I am getting a spark.

I also checked the flywheel key and it looks fine.

I took apart the carburator and everything seems to be moving fine (though I may not have gotten the two screws on top to their original positions).

Took off the muffler to make sure it wasn't clogged. It isn't.

Is there anything else I could try/test to try to get this thing started again?

One thing: when I pour gas directly into the spark plug hole, replace the spark, and pull the cord, the thing doesn't so much as briefly sputter.

Any suggestions?

Thank you for your time,
Brian
 

MBDiagMan

LawnSite Senior Member
Location
NE Texas
You say you are getting spark. Is it a fat blue spark or an orange spark? If orange, then the spark is weak.

The only other things would be lack of compression or timing problem. Have you done a leak down test?

Good luck,
Doc
 

lawnmaniac883

LawnSite Silver Member
Location
largo, FL
Dont worry about a leak down test on a two stroke, if you want to check the pressure being built up, then by all means do so with the proper equipment (forgot name of test instrument) but I think your problem is a timing issue. Did you perhaps replace the magneto upside down?
 

Lawn Masters

LawnSite Senior Member
Location
Hudson Florida
Its possible that the problem is relating directly to timing, and I suspect that myself from what you describe. try replacing the flywheel key, and adjusting the air gap on the coil of this engine to the thickness of a matchbook cover, not a business card. the matchbook is more likely to get the gap right, and you'll probably get a better spark from it then.
 
OP
C

calhoontuna

LawnSite Member
Location
Sussex WI
No luck.

I replaced the flywheel key and gapped the magnito with a matchbook. Still does the same thing.

Could the timing be screwed up at some other, deeper, level?

What do you make of the fact that the sparkplug seems dry after a few pulls. I checked and the gas is getting as far as the carburator fine.

Brian
 
Top