On Thu, 11 Feb 2010 13:11:52 -0700, "Paul Hovnanian P.E."
wrote:

Existential Angst wrote:

Awl --

Always the carburetion, it seems.

Last snow, a month or so ago, ran fine, a Sears "6.0 hp" ditty.
Today, it would run for only 10 sec, and would have to constantly be
re-primed and started. Choke is OK, full gas. Once in a blue moon it would
run for a minute, but not under load.

I could actually sort of see the primed gas spill out of the carb, which
would apparently fuel the engine for a while. Seems that the running engine
couldn't draw it's own gas.

Many of these small engine carbs have a built in fuel pump which
consists of a diaphram that is driven by the pressure variations
(pulses) in the intake manifold.

If that diaphram is cracked or there's a vacuum leak in that system, it
won't pump its own gas. It will appear to run when primed, but that
won't last long.

A carb rebuild kit should have the parts to remedy this problem.


Being a "Sears" it most likely has a Tecumseh SnoKing H6 engine on it
- which does NOT have a fuel pump. Most common problem is moisture in
the gas - and the water blocking the main jet.. If at all possible, do
NOT use ethanol fuel. Use premium if that's the only way to ensure
getting ethanol free fuel. Premium will NOT hurt the engine, and runs
it just fine. (So does 100LL AvGas - but you can't just go and buy
that)

Fresh gas, drain the float bowl, and add some Sea Foam to the fuel to
clean up the carb.