Engine RPM's while mowing?

pgmrdan

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The Kubota Rotary Mower Operator's Manual states "Keep the engine at full throttle for best results." Really?

I kept the engine running in the PTO 540 range while using my mower for the first time yesterday. Should I run the engine faster? Is it safe to run the engine at full throttle?
 

Pawnee

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Sounds like an error, that phrase may have been included from a riding tractor manual.
If you have a 540 RCR then you run the PTO at 540.
Usually there is a mark on the tach that shows where that occurs.

Maybe post which tractor and which rotary cutter.
 

BAP

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The Kubota Rotary Mower Operator's Manual states "Keep the engine at full throttle for best results." Really?

I kept the engine running in the PTO 540 range while using my mower for the first time yesterday. Should I run the engine faster? Is it safe to run the engine at full throttle?
What model tractor? Stating that is going to give you the best answer. Most tractors will have a mark on the tachometer that says PTO like you have asked about. That’s the rpm that you want to use. If you are using a Kubota mower that is not a tractor then the full throttle may be the appropriate choice.
 

GreensvilleJay

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Not all grass was created equal.

You'll find you don't need '540' on the tach ,let alone full thottle(WOT) if you're trimming dry grass. However trying to 'brushcut' or hack 12" tall wet grass at Mach 2..well, even WOT isn't fast enough !

One of life's 'learn by doing' experiences.

Though I do know 3 'experts' that say you can cut grass when it's wet.....
 

TheOldHokie

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The Kubota Rotary Mower Operator's Manual states "Keep the engine at full throttle for best results." Really?

I kept the engine running in the PTO 540 range while using my mower for the first time yesterday. Should I run the engine faster? Is it safe to run the engine at full throttle?
"For best results" run PTO at the rated input speed of the mower.

Dan
 
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skeets

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If you are running a BX then WOT for a MMM is what you should be running, for rear mounted or fount equipment 540 RPM is what you should be running
 
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N3BP

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Depending on your machine, the 540 notch on the tach and full throttle are only a few hundred RPM apart and are both acceptable positions to run the MMM in.
 
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Old Machinist

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My new to me LX3310 says 2500 RPM is the correct PTO speed. Full throttle is exactly 2500 RPM on the tach. Could be they have adjusted the throttle to prevent over revving.
 

North Idaho Wolfman

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Whatever! When I pull my throttle lever to fast stop the RPMs go to the prescribed 2500 RPMs.
WOW, so sorry to offend you with knowledge on how it really works! :oops:
I guess drilling a hole is the same as reaming a hole. :unsure:
 

chim

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Different speeds work better at different times for me. Recently that's been between 400 and 450 RPM. A bit over 2000 engine RPM
 
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jaxs

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My new to me LX3310 says 2500 RPM is the correct PTO speed. Full throttle is exactly 2500 RPM on the tach. Could be they have adjusted the throttle to prevent over revving.
If you think that's what your LX3310 ( or operator's manual) says you need to go back to what it says about operating under the influence. PTO rpm and engine rpm are two different things.
 

North Idaho Wolfman

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If you think that's what your LX3310 ( or operator's manual) says you need to go back to what it says about operating under the influence. PTO rpm and engine rpm are two different things.
I think you owe him an apology. ;)
He also doesn't like knowledge.

1717379424846.png
 

Old Machinist

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My new to me LX3310 says 2500 RPM is the correct PTO speed. Full throttle is exactly 2500 RPM on the tach. Could be they have adjusted the throttle to prevent over revving.
I merely made a relevant observation that my Kubota's Full throttle setting is what the manual states as the correct RPMs for PTO operation.
 

Old Machinist

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Not the throttle, the governor does that (either electronic or mechanical).
I am fairly new to the forum.

I have seen several "I'm smarter than you" posts on this forum that are neither relevant or helpful. Seeing it from a moderator may indicate this mentality is deeply seeded and this may not be a place I am comfortable sharing My Knowledge.

I am fully aware of how a governor works. I was a certified MASTER AUTO TECH for 25+ years before turning to machine work for another 19 years before retirement.

Nowhere in My OM does it discuss a governor. It tells you how to operate the "throttle" and it tells you the correct RPM setting for PTO operation. 2500 RPMs on My model results in 540 RPM rear PTO speed and 2500 RPMs for the mid PTO. My observation to the OP was the full throttle setting on MY Kubota WAS the indicated PTO RPM.

Any more attempts to insult me may fall on blind eyes. You guys are TOO smart for me to learn from.
 

North Idaho Wolfman

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I am fairly new to the forum.

I have seen several "I'm smarter than you" posts on this forum that are neither relevant or helpful. Seeing it from a moderator may indicate this mentality is deeply seeded and this may not be a place I am comfortable sharing My Knowledge.

I am fully aware of how a governor works. I was a certified MASTER AUTO TECH for 25+ years before turning to machine work for another 19 years before retirement.

Nowhere in My OM does it discuss a governor. It tells you how to operate the "throttle" and it tells you the correct RPM setting for PTO operation. 2500 RPMs on My model results in 540 RPM rear PTO speed and 2500 RPMs for the mid PTO. My observation to the OP was the full throttle setting on MY Kubota WAS the indicated PTO RPM.

Any more attempts to insult me may fall on blind eyes. You guys are TOO smart for me to learn from.
Heck I even defended you on your answer.

Sorry your viewing my trying to be helpful as an insult.

I'll just let you be...
 

jaxs

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If you think that's what your LX3310 ( or operator's manual) says you need to go back to what it says about operating under the influence. PTO rpm and engine rpm are two different things.
I misspoke, according to specs above your pto speed is indeed 2500 which sounds insanely fast but it's right there in black and white. I can't keep farm tractors and amphibious lawn mowers sorted out which isn't good when talking about Kubota. I just learned something else ,according to spell check Kubota is both singular and plural. No such thing as Kubotas.
 

BAP

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WOW, so sorry to offend you with knowledge on how it really works! :oops:
I guess drilling a hole is the same as reaming a hole. :unsure:
Actually Wolfman your answer was not totally correct. Tractor manufacturers and other equipment manufacturers set the rpm limits for operating using adjustable stops on the throttle linkage. Yes the governor helps control and maintain the speed but the throttle stop on the linkage keeps you from adding more fuel and speed to the engine, keeping it at a prescribed speed.