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Proper engine speed for average mowing work


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Now a question.
What is the proper throttle position (engine RPM) for normal mowing applications? That is mowing mostly flat areas with about 1/3 of the grass on a gentle 5-7 degree slope. I mow a total of 1 to 1.3 acres with a 416H / 48" deck. The job goes faster at full throttle, but I am afraid of pushing the engine/tranny too far. Something in my gut says a bit below full RPM is safer, but then again I'm not sure. If I can run it at full speed safely, I sure as hell will.
Paul L..
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Brs and Kohler have governed speeds spec'd. Usually 3300 to 3600, The 243000 series in the 10 hp Landlord was spec'd @ 4000. These engines should run at near these speeds. The air flow from the fan is not a linear function, and double the speed gives much more than double the air flow. Closer to square law. (4 TIMES). Running at part throttle causes exhaust valve seats to come out. etc due to overheating. Engine is lugging generating mush more heat with much less cooling.
Last yr we had a 7 yr old Br. Vangard that dropped a valve seat, Talked to Brs Serv rep. First question, Is customer mowing at part throttle? This is the most common cause of valve weats coming out. I cclled customer and asked. He said yes about 3 weeks ago we hired an older gent. to mow and he doesn't like to run the engine too fast. They were right on.
My 2 cents worth. AL
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Paul, I have heard many times that an air cooled engine should always be run at full throttle for proper cooling and lubrication. I run my 32 year old B12 at full throttle when mowing and it doesn't seem to hurt it. The mower also works best at the higher speed. Tim
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I always mow at full throttle to keep the blade speed
as high as possible. The point is to cut the blade of
grass with minimum damage to the grass blade, as well
as getting the blade to be as vertially oriented as
possible to get even grass height. A faster blade is
better at achieving these goals.

The governer, if adjusted properly, will keep the
engine from over-reving. Besides, it's not usually
speed that destroys these engines, it's a heavy load,
and running at the highest possible rpm actually
lessens the load on the engine when the tractor
encounters a heavier load.

That's my two cents worth.
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