What's likely the problem, is a bad gasket between the carb
and the engine. If there is a gasket, put on some Permatex
#IIa, non hardening gasket sealer. Might be sucking air from
the gasket, which is after the carb. This is a common
problem, and the symptom is usually "won't start unless I
pour some gas in the air intake".

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Taylor" wrote in message
...

My snow blower has a Briggs & Stratton 7.5 hp "Powerbuilt
Snow"
horizontal engine. It has always need a little choke to run
smoothly
after it warms up. With no choke it runs, but stumbles
slightly. With
one click it is a bit smoother, and with two clicks it runs
the
smoothest. More than that, there is too much choke and the
engine will
die.

Thinking that perhaps something is clogged in the
carburetor/jet, I
replaced the whole carb with a new one. The result is
exactly the same.

I have fresh gas, use Sta-Bil, etc. I'm not overly worried
about it, I
just use two clicks of choke for best power.

However, I suspect that I'm not getting the full 7.5 hp with
the choke
restricting air intake. I'm also curious what the problem
is. A
repairman said that all engines are tuned lean due to EPA
rules. Of
course there is no way to adjust the mixture.

Any ideas what causes this? Is the repairman right about
the mixture
set overly lean on purpose?