3,600 is typical for these engines. They will tolerate more however. We
set most of ours to 4,000 - 4,100

--
Steve Barker




"Jeff Wisnia" wrote in message
...

I've got a 21" Toro self propelled rotary mower with a 3.75 hp Briggs
engine on it.

Whe I used it today for the first time this season I had a feeling the
engine might be running a little slower than it had in the past, as I
seemed to be walking "less fast" to keep up with it.

I measured the RPMs with my non-contact tach and the engines's "full
speed" with no load was 3,000 RPMs, and it didn't sound like it dropped
off significantly under load.

My memory is telling me governed full speed for that kind of setup should
be more like 3,500 RPM. Can someone confirm that?

The governor seems to be doing it's job, but I've got a feeling it's
spring has stretched a bit over the years. The engine speed will increase
fine if I "assist" the spring with my fingertips, so I can probably tweak
the speed up by rebending the throttle lever end of the spring to make it
a bit shorter, (or by buying a new spring). The other end of the spring is
as far away from the throttle lever as the speed control lever can go.

Thanks guys,

Jeff
--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.