New mower engine speed

Weed Hopper

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I just bought a 320r zero turn mower and have read that running at less than full throttle may damage the hydrostatic transmission. So, my question is, "Should I always run the mower at full throttle?"
 

Bertrrr

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It's designed to run at any speed you choose , the governor is set to keep it from over revving, you have to run it enough to let the charging system do it's job in keeping the battery up. I rarely run my machines more than 3/4 throttle - just don't see the advantage of running anything wide open. - just the mechanic in me I guess
 

ILENGINE

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The answer to your question is yes it needs to be run at full throttle due to the hydrostat needs a range of rpm's that allow adequate oil pump flow and also cooling. Also the engine cools best at full rpm, and running at half throttle causes the engine to also run hotter due to lack of cooling air flow.
 

Rivets

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Ditto what IL says as todays hydros operates best when run at full throttle.
 

Weed Hopper

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Thanks for corroborating what I suspected. Full throttle from now on.
 

bertsmobile1

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And to really drive it home
Hydros must always run full speed or too much oil escapes between the vaalve plate & cylinder block
The accelerates the errosion in this area which is how 99.9999% of hydros fail and what makes that growing sound .
IT is also why the left side on ZTR's always fails first .
 

Tiger Small Engine

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And to really drive it home
Hydros must always run full speed or too much oil escapes between the vaalve plate & cylinder block
The accelerates the errosion in this area which is how 99.9999% of hydros fail and what makes that growing sound .
IT is also why the left side on ZTR's always fails first .
Wide open throttle when under load with blades on! Read up on it if you don’t understand or need further information.
 

MParr

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If the blades are on and you are cutting grass, run it at full throttle.
 

StarTech

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And to really drive it home
Hydros must always run full speed or too much oil escapes between the vaalve plate & cylinder block
The accelerates the errosion in this area which is how 99.9999% of hydros fail and what makes that growing sound .
IT is also why the left side on ZTR's always fails first .
Then I wonder why the RH on a customer's Bad Boy ZTR failed first here.

I would there are exceptions.
 
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