none wrote:

snip

of faulty idle on a Tecumseh carb is if you try and run them with a
rotted primer bulb or dirty gas.(Tecumseh uses a counterbalanced
govenor system that literally makes for a rock steady idle, unlike
Briggs which are famous for up and down idle states.)

Odd. I have exactly the opposite. B&S lawnmower is the
worst engine I've ever had, but idles so smooth so slow
that I can't imagine why it keeps running. Just does.

Tecumseh snow king engine is the best engine I've ever had.
Starts at -40 degrees with just a single tug on the starter.
Electric start, and even though I'm an old guy, I don't bother
plugging it in. But at anything less than full open, it
idles up and down so bad it's scary. Goes from what sounds
like wide open to almost stalling and back again. Over and over.
Looking at the spring on (or near) the carb, it goes from
tightly stretched to so sloppy and loose that it looks like
it should fall off.

Ken