"Asimov" writes:

"cnctut" bravely wrote to "All" (11 May 05 10:52:14)
--- on the heady topic of " Lawnmower idle question"

From the small motor faq:

" Air vane governor. The air flow provided by the
flywheel/blower passes by a plate which is coupled to the
carburetor throttle plate acting against a spring force.

Flyweight governor. A spinning gear assembly with a pair of
weights is driven by the camshaft. As the centrifugal force
of the weights increases, they move a sleeve which presses
against a lever whose shaft passes through the crankcase.
This lever then operates the carburetor throttle plate
against a spring force.
With both types, increasing the spring force will increase the
engine speed.
"

Hunting is often caused by a defect in the governor system. Check the
blade (plastic?) of the governor paddle is free to move and that the
cam to which it connects has the proper spring tension. As the motor
speeds up the flywheel impellor blows air against the blade and cuts
the trottle down. When the motor slows down the blade drops back and
the spring returns the throttle higher.

One note though: He has an idle speed problem where the governor is
likely not involved unless it is way misadjuated.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
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