Vintage Sears Garden Tractors
I was having trouble with a lean mixture that no
amount of screw twisting could resolve. I figured a
passage was clogged, so off the carb came for a
cleaning. I noticed that the petrified intake gasket
was gone near the holes, but full thickness in the
middle. A check of the mounting flange revealed
that it was warped. Age, overheating,
over-tightening and reuse of the old gasket had
taken their toll. An air leak here, or anywhere not
intended, will make the mixture overly lean for
sure.
My low-tech solution to the problem was to sand
the flange flat. The flattest surface I have in the
shop is a cast iron saw table. I used emery cloth
laid on the table to sand it flat. I moved the carb
back and forth on the long axis, i.e., aligned
through the mounting holes, while applying
pressure straight down on the carb body. I was
surprised at how quickly it flattened out. Be
careful if you do this. If you don't keep enough
downward force on it when moving back and forth,
you will make it worse than when you started. Use
a finer piece of emery to clean up the scratches
made by the heavier grit and you'll be good to go.
Of course it was a Sunday afternoon when I was
doing this, so getting a Tecumseh gasket was out
of the question. The next best thing is to make
your own. It's easy to trace the outline onto gasket
material and cut it with a straight razor blade. I've
found that using a 2X4 as a backer when cutting
the gaskets works well. A standard hole punch was
used for the holes. That makes them a bit
undersized, so I used a drill bit (finger powered
only so as not to rip the material) to make the
holes the right size. The gasket on the right is for
the air cleaner assembly.
Warped Carburetor Flange
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© 2011 VSGT