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.


If its a 70s mower with a 10-year-newer B&S engine, that would mean its
an 80s-vintage B&S. That would be about the lowest point in the armpit
of quality of B&S carburetors, and it agrees with your symptoms. The
"pulsa-jet" carbs of that era used the vacuum pulses of the intake
runner to operate a diaphragm that pumped fuel up from the tank to the
carb. They also had a vacuum-operated choke that had a tendency to not
choke enough when cold and choke too much when hot. They tended to work
fine once you got them running, but they were HARD to get going the
first time because there just isn't enough vacuum pulse to pump the fuel
while you're yanking the rope. Especially when they aged a little and
the pump diaphragm got a little stiff You could try a carb rebuild kit,
but frankly the only way I ever made an 80s Briggs run truly great was
to scavenge the carb (and fuel tank) off an older (70s or even late 60s)
engine.