On Sat, 23 May 2009 16:30:46 -0700 (PDT), muzician21
wrote:

Have a B&S on a 70's era Snapper 21" pusher with an aluminum deck. I
believe the engine is probably 10 years newer than the rest of the
mower.

Maybe 10 years ago I took it to a repair shop who installed a solid
state unit to replace the points. Even with the solid state ignition
it was never one-pull start, but as I recall it usually started with
probably 3 - 5 pulls. Now it takes probably 20 pulls or more and
monkeying with the throttle. Once it fires it runs like a clock, runs
up and down the speed range fine. It's also easier to re-start once
it's been running - though still not one pull. Doesn't seem to use an
inordinate amount of oil, no discernible smoke out the exhaust. It
gets what I'd call moderate use. I'm in central Florida so it gets run
bi-weekly or so during the rainy months, not at all during the months
of what passes for a winter down here.

I'm mechanically inclined but not well-versed on the theory of this
kind of engine. I've had it broken down far enough to remove and flush
the gas tank, change the points when it had points, replace the pull
rope. I've change the spark plug of course. I know it should start
much easier than it does. Any suggestions where to look, what to
tweak? There isn't that much to it from what I can see, so it
shouldn't be that difficult. I believe this mower has a lot of life
left in it.

Thanks for all input.

Not familiar with this particular engine, but it sounds like a gas
delivery/mixture problem. Choking can be real critical with these.
This is the first year I've had no problem starting my 2-cycle
weedwacker because I've learned the primer bulb needs to be pumped up
hard, the exact choke setting it likes, and that it has to be unchoked
immediately upon firing. Only took me 5 years, but I've got it
starting in 3 pulls.
I'd start by maybe looking in the carb for wetness, and trying 3 to 5
pulls at different choke settings. But you have to let it dry out
between tries so you're not confusing the issue.
Once you know what works, you're all set. Until it doesn't work any
more.
That's what I like about the Honda I have on my Craftsman.
3 horse I think, 4-cycle.
It starts first pull after sitting all winter. Every time for about 6
years now. Original plug.
And I never drain the gas or use a gas additive on anything.
Not saying don't, just that I don't bother.

--Vic