2540 PTO engagement

[sideskraft]

Is there any way to "ease into" the PTO during engagement? I'm pushing in the clutch, moving the PTO lever on the left side to the ON position, then with the clutch still depressed, pushing the PTO switch on the dash. The engagement is sudden and immediate and can't be good for the tractor or implement. Is there some way to slowly engage the PTO using the drive clutch? This is my first "real" tractor so I'm unfamiliar with how PTO engagement works on other tractors.

 

[Agvg]

You must engage at low rpm and this way with very direct egagment is very common on tractors for decades so it's not a big problem.

 

[bridge4]

I pretty much do the same thing on my 2638. Ive found it to be a smooth process with no loud noises or shaking. The 3 part engagement on these especially with the auto on and off setting seems to work well. When it does it on auto, you don't need to lower rpm, so I don't think you would otherwise either?

I could be totally wrong as this is my first real tractor as well.

 

[duffer]

Agree totally with Agvg. The lower the RPM during PTO engagement the less stress you exert on your equipment. Engaging at full throttle or anything above idle speed for that matter, just puts exponential stress on the dry-shaft, gears, belts, tranny, everything.

 

[sideskraft]

You must engage at low rpm and this way with very direct engagement is very common on tractors for decades so it's not a big problem.

That's what I always do -- engage at idle speed. If and when we can afford it, I'd like to get a 6 or 7 inch capacity PTO wood chipper, and those have drums or flywheels that are 150 lbs or more. That's a lot of weight to turn from stationary to full engagement in less than a second. I've heard of some posters breaking shear pins just by engaging the PTO with those chippers. I would assume that larger tractors have some kind of clutch system for PTO engagement based on the size of equipment they can operate.

 

[sideskraft]

Agree totally with Agvg. The lower the RPM during PTO engagement the less stress you exert on your equipment. Engaging at full throttle or anything above idle speed for that matter, just puts exponential stress on the dry-shaft, gears, belts, tranny, everything.

I'm in 100% agreement with that. I've seen people with lawn tractors engage the mower PTO at full or close to full throttle and cringe at the thought of what that's doing to the machine. I believe that those do have clutches built in to them to prevent gear or other breakage, whereas compact tractors (at least mine) do not.

 

[ptsg]

These tractors have electric over hydraulic PTO clutch. The switch just turn the solenoid on and off, no modulation whatsoever. So pressing the clutch pedal won't really make a different.

Then the PTO valve controls the clutch pack. It usually have an accumulator and a sequence valve to let the clutch pack slip a bit and create the soft start effect.

For some reason, it doesn't work that smoothly in most tractors. I think it has something to do with the load on the PTO but I don't have a PTO attachment like a wood chipper to test that can put a longer load when starting up the PTO. I'm wondering if the higher the load and/or slightly higher RPM, the soft start feature will behave smoother.

 

[sideskraft]

These tractors have electric over hydraulic PTO clutch. The switch just turn the solenoid on and off, no modulation whatsoever. So pressing the clutch pedal won't really make a different.

Then the PTO valve controls the clutch pack. It usually have an accumulator and a sequence valve to let the clutch pack slip a bit and create the soft start effect.

For some reason, it doesn't work that smoothly in most tractors. I think it has something to do with the load on the PTO but I don't have a PTO attachment like a wood chipper to test that can put a longer load when starting up the PTO. I'm wondering if the higher the load and/or slightly higher RPM, the soft start feature will behave smoother.

Thanks ptsg, that's very interesting. If what you're saying applies to my tractor, that would make sense. My only PTO driven implement is a 6ft rotary cutter, and I can tell you that there is no slippage when the PTO button is depressed -- it's zero to fully engaged in a split second. Maybe with a heavier load there is a built in "slipping mechanism" that would extend the engagement period.

 

[ptsg]

Thanks ptsg, that's very interesting. If what you're saying applies to my tractor, that would make sense. My only PTO driven implement is a 6ft rotary cutter, and I can tell you that there is no slippage when the PTO button is depressed -- it's zero to fully engaged in a split second. Maybe with a heavier load there is a built in "slipping mechanism" that would extend the engagement period.

That's my case as well. I only have the brush mower and a tiller as far as PTO implements. Since the tiller is just a slow rotation implement, doesn't make much difference at all. Depending on the land I have to till, I usually use the Auto mode with the tiller instead of the Independent mode.

The mower, as we use chains (not blades) on the brush mowers here, it will hit a bit hard on the metal above.

I forgot to add one thing to my previous post. This type of electric over hydraulic PTOs, also have a spring actuated brake when in the OFF position or the tractor is not running. So having more than one speed at the PTO helps you a lot because you'll then have a lever to switch between PTO speeds with a Neutral position in the middle. This Neutral position will allow you to rotate the PTO shaft by hand when hooking up to the implement, which otherwise you couldn't rotate it.

 

[JerryK]

With a hyd PTO clutch, some tractors employ a small tank in between the PTO clutch and the hyd valve. This device, sometimes called an accumulator, slows down the abruptness if installed and designed correctly. I believe my 5035 has one. At least I think I read that the first 35 series had a small problem, and they added an accumulator to the PTO circuit to correct operator be atching. The 5035 is the old version of the 3550, etc. they sell nowdays. If you send me enough buckazoids, I will crawl under her and take pictures for you...