4x20 PTO?

   / 4x20 PTO? #3  
Assuming the 4X20 PTO is unchanged from the 4X10 large chassis (4510-4710), then the PTO is hydraulically modulated. Even though the switch is on/off, the PTO valve (located under the SCV) does include modulation. Probably the biggest inertia startup I have experienced has been with a 4710 and an MX8 mower. It handled the startup well.
 
   / 4x20 PTO? #5  
"Modulated" is a relative term. It took me a while to find the sweet spot (1500 rpm) to start up my MX6 with my 4710, and it's still quite a jolt. Probably my number one complaint with my 4710 specifically and the overall movement towards binary (on/off) controls. The new 5000-Twenty Fives have gone to a similar PTO control.

Probably would not be a bad idea to buy all slip-clutch setups for anything that represents a hard start-up load.

I think the major force behind this control design is the legal staff, not the engineering group. With the Deere setup it's very easy to incorporate the PTO control into the operator presence system. Not a bad idea but it could have been executed better. How about a switch (they could use the current yellow mushroom) that simply 'energizes' the solenoid to allow hydraulic flow - BUT give me a simple lever that then opens the flow to the clutch. That allows me to modulate taking up the PTO load, but instant cut-off if the safety circuits cut in.

IMO sometimes new and improved isn't.
 
   / 4x20 PTO?
  • Thread Starter
#6  
The push button control for PTO engagement isn't necessarily a bad thing as long as the control has some electrohydraulic smarts behind it.

In the Deere line, all their AG tractors from the 6020 series and up have push button PTO switches. However, they specifically mention that the PTO control has "electrohydraulic controlled modulation to ensure smooth engagement".

In the 5025 series, the push button "eletrohydraulic" PTO control is only included with the new 24F/24R transmission (also electrohydraulic). They still use a lever for PTO control with the ability to "manually feather the PTO for smoother engagement" with the 9/3 and 12/12 transmissions.

I also spent some time with Deere's online 4x20 CUT operators manual to see what they say about PTO engagement. Sure enough, it boils down to stopping the tractor forward motion (reverser in neutral, foot off fwd/rev pedals on eHydro), reducing the engine RPM to 1500, pull the PTO knob, and speed the engine RPMs back up to 2400 for rated 540 RPM PTO speed.

Well, I must say that IMO this is a definite area for improvement on the 4x20 series CUTs. Especially since I'm finding out through TBN that other CUT brands do have live independent PTOs with modulated (manual or otherwise) engagement.
 
   / 4x20 PTO? #7  
That is of interest to me, as I like the PTO setup on my Deere 4300. It has a clutch engage lever that has a 'neutral' (free spinning PTO), a 'stop' that engages a brake, and an 'engage' that can be feathered in carefully, or quickly, whichever one wants.
I can let the rotary cutter spin down on its own, or brake it to a stop if conditions warrant.

I will miss that feature if the 3520 doesn't offer something similar. /forums/images/graemlins/tongue.gif
 
   / 4x20 PTO? #8  
If you look at the larger machines, you will see all sorts of amazing time savings devices. You can get everything from electohydraulic hitches to satelite control.

On these machines, you have to stop and lower engine speed to engage the pto. It is less conenient. It is safer. It keeps costs down. If you have to be able to feather it in, without stopping and lowering engine speed, then they might not fit you.
 
   / 4x20 PTO?
  • Thread Starter
#9  
With all due respect -- and just so everyone knows, I do tend to bleed green /forums/images/graemlins/smile.gif -- it looks like the PTO control is a design compromises that John Deere had to make to keep the cost down on the 4x20 series CUTs.

Although I'm sure you can learn to engage the 4x20 PTO effectively given its design limitations, I do find it odd that my 33 year old John Deere 1020 -- a small 38 PTO HP utility AG tractor -- has a fully independent, live, and hydraulically actuated PTO.

Just grab its control handle between the two gear shift levers and slowly feather in the PTO as needed given the attachments' inertial requirements. And you can do this at any RPM, in gear or out, transmission clutch in or out, and tractor moving or not. It is a very productive way to use a PTO.

And yes, I may need to consider looking at something like the 5x05 or 5x25 series tractors from JD (got to have 4WD if I replace the 1020!). But then again, there is always the price thing... Funny how that always raises its ugly head! /forums/images/graemlins/smirk.gif
 
 
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