Zero Turn w/ Kawasaki FX850v: Mowing RPM / Full Throttle?

  
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Rdrcr

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^^^^
After posting this thread and getting excellent responses, I re-read my manual and it does state to engage the PTO at half throttle and run the mower at full throttle. I’m following the manual’s instruction.

However, it is interesting how some machines engage the PTO at half throttle and others at full throttle???

Mike
 
   #22  

N80

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You made me wonder if I'd read my manual wrong so I went back and checked:
  1. Move the throttle to the FAST position.
  2. Pull the PTO switch up/out into the ENGAGED (ON) position.
  3. NOTE: When operating the tractor be certain that the throttle is always in the FAST position. Operating with the throttle at less than full throttle may lead to premature battery wear and a poor quality cut.
My totally unqualified opinion is that everyone should follow the manual on their machine.
 
   #23  

RSKY

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My Bad Boy will stall the first time I engage the blades if not running at full throttle. I also have the mower rolling when engaging. After mowing for a minute or so it will engage without stalling at just a few rpm above idle.

RSKY
 
   #24  

f800

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I engage mine just above an idle. The electric PTO clutch is just like the ac clutch on your car. A driven plate with brake material and a drive plate. Engaging it at RPM hastens the wear on the friction material and wears it out faster and you don't want to replace that clutch because none of them are cheap.

Just replaced the one on my M60 Tank and it was 250 bucks.

Guy across the road has a Husky and winds the engine up and engages the blades. Bet he stops doing that when it's clutch time.

Again, WOT is maximum governed rpm, usually around 3600. The higher the rpm, the faster the blade tip speed is, the better the blades cut and the engine cools too. Remember, they are air cooled, least both of mine are. I'd love to have a Kubota diesel but alas, I cannot afford the price of admission.
I have a JD 997r for my residence and love it, but in no way can afford American tracked armor (except for maybe a halftrack), but, you have an M60, and can’t afford a Kubota diesel?? BTW, I don’t always mow at full throttle because I don’t need to. Wondered if it had any deleterious effects in the mower. I engage blades at half throttle.
 
   #25  

N80

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My manual says to mow at full throttle for better blade speed and cut quality as well as properly charging the battery. I've seen tear down videos of dead engines that claimed they were run at lower throttle speeds which caused overheating. I can't attest to the validity of those videos though. However, I'm assuming these engines were designed to perform best at a certain RPM which is where they are governed and thus the recommendation to run at WOT.
 

Frankenkubota

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You made me wonder if I'd read my manual wrong so I went back and checked:
  1. Move the throttle to the FAST position.
  2. Pull the PTO switch up/out into the ENGAGED (ON) position.
  3. NOTE: When operating the tractor be certain that the throttle is always in the FAST position. Operating with the throttle at less than full throttle may lead to premature battery wear and a poor quality cut.
My totally unqualified opinion is that everyone should follow the manual on their machine.
Mine-said the same, engage at full throttle to avoid excessive belt wear.
 

nh15201

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I may have to revise my PTO engagement on our CC 560? I have been having my wife engage the PTO at half throttle - with the deck lift pedal depressed so the blades are out of the high grass, then go to WOT and then let the deck down to start mowing. I admit that when I mow with it - I will decrease throttle speed slightly in areas where the grass isn't too high and/or very dry. I need to remember that air cooled engines require WOT to cool efficiently when under load.

On another note, since it seems that the Kawasaki engines are widely used - across many different models - is there a specific Kawasaki engine thread?
 

sklunk

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Okay here is my modest .02 (from an Aerospace Engineer who is familiar with airflow):
  • ALWAYS mow at full throttle. Commercial ZT decks are designed to stand the grass blades up, get very high blade tip speeds, and exhaust the clippings faster for a better cut. The airflow in them is optimized for best performance at full spindle rpm. You can slow the "driving speed" of the machine down with the hydros or gears but you should keep the throttle at WOT once the blades are engaged. It becomes even more important if a bagging system is attached.
  • As others have stated it is also better for air-cooled engines to run at WOT so that's another reason to run there.
  • As far as engaging the PTO -- FOLLOW THE MANUAL. Most PTO's on these machines are electrically engaged. On the "traditional" ones that have been used for decades it is definitely better on the PTO to engage at lower RPM/throttle, this saves wear and tear on the PTO. However since they are electric some of the newer models are now including a soft-start feature in the PTO. If this is the case they are okay to engage at full throttle. There isn't an easy way to tell which style you may have so it is better to just follow the manual.

Hopefully this helps.
 
 
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