Mowing Float position and mower decks

[toolz_not_toyz]

Okay. If I can swing it I'm going to hop onboard the PT wagon before the year is out. I've been going over my previous posts, re-examining my equipment wish list and have changed it all again. Ugh.

I thought I wanted the 48" mower deck but now I'm not sure. Along the way someone suggested I might consider the bush cutter deck instead. I do have some lawn out front and back. The type of thing that would take a lawn tractor maybe 45mins to finish off. But out back out back I currently have a lumpy mess that needs to be cut down and then maintained. I have no problem doing the initial messy work using my line trimmer with a flail head.

The flail head strategy worked really great clearing about 1/2 an acre at the old place--and that stuff was about 3 feet high. Here I just have tall grass, weeds, ferns. I think the topology underneath all of that messy stuff is very uneven (lumpy!).

What I don't get about the mower decks is that they are on wheels. My old lawn tractor (sold with the last house) had a floating deck. The PT deck is clearly different but I don't understand how the deck can rest on the wheels and move with the contours of the land if it is also suspended by the arms. I don't understand the term "float" position when discussing the PT. Can someone clue me in?

And can the brush cutter be used on unlevel land? And if so, what is the difference in quality between its cut and the 48" finish mower?

 

[MossRoad]

It isn't really suspended by the arms as long as the FEL joystick is pushed all the way forward in the float mode. The deck rolls on its own wheels and the PT just pushes it forward. It is free to tip forward and backward, roll left and right, and raise up and down on its own, independant of the tractor.

In situations where you are going up hill, if you start to lose traction with the front tire of the tractor, you can pull the joystick backwards, out of float, and transfer the weight of the mower deck to the front tires of the tractor. However, at that point, the deck will not raise and lower independantly of the tractor, because the FEL arms have been locked. The mower will still roll left and right and tilt forward and backward in the non-float mode.

 

[MossRoad]

Here's a link to a video of me mowing with the PT425 and 60" deck.

This is the corner of my front yard, where the drive meets the street. The yard slopes down to the drive and to the street. The first part of the video shows me coming from left to right. I am tilted at about a 10 degree angle to the operator's left and am running parallel to the driveway. As I turn to my right I am still on that 10 degree slope. I follow it around 90 degrees and parallel the street, still at a 10 degree slope towards the street. No wheels on the mower deck or the tractor ever leave the ground.

In the second part of the video, I attack the slope head on. The mower climbs the slope first, followed by the tractor. It is kind of hard to see, but the mower deck just floats up that hill and is about a foot higher than where it started before the tractor makes the climb. By the time the front wheels of the tractor reach the top of the hill, the mower deck is actually lower than if the whole thing were on level ground.

Think of it this way... as I move forward up that hill, the FEL arms go from level with the centerline of the tractor wheels, to about a foot higher than the centerline of the wheels, to about a foot lower than the centerline of the wheels, then back to level with the centerline of the wheels.

It really is a neat system. Any attachment that goes on the FEL arms works the same way, wether it be the mower, brush hog, snow blade, power broom, rakes, etc.... hope that helps? /forums/images/graemlins/crazy.gif

 

[KentT]

Good description, MR! /forums/images/graemlins/cool.gif

 

[toolz_not_toyz]

Thanks MR. That helps a lot. So "float" is a setting that's engaged by the joystick? Are the hydraulics for the arms simply bypassed when that setting is engaged?

I did look at your videos again. I have downloaded them all in case they disappear. I just didn't understand what was happening. Make sense now.

 

[MuncyBob]

I'm not sure exactly what happens in the hydraulics when the float is engaged but you still have control of the forward and backward tilt....once in float I use the joystick to then get the deck at the midway point and off I go. With all the contours in our land the float does a reasonable job of an even cut.

 

[KentT]

</font><font color="blue" class="small">( Thanks MR. That helps a lot. So "float" is a setting that's engaged by the joystick? Are the hydraulics for the arms simply bypassed when that setting is engaged?

)</font>

Yes, as shown on this pic, the float is engaged with the joystick..

Pic of control label for the joystick

You lower the implement to the appropriate level and then quickly push the joystick farther forward. There's a detent positon there that will "click in" and you can feel it through the joystick. Then you release the joystick to leave it in float -- if you try to control it manually, it will come right back out of float, defeating your purpose.

As I understand the hydraulics, this setting allows the hydraulic fluid to freely move back and forth from one side of the lift cylinder to the other -- so that it doesn't maintain pressure on the cylinder in either direction, neither lift nor down-pressure. There is still some resistance to up and down movement of an implement in float position, since the fluid has to flow through the control system and to the other side of the cylinder. It operates in float position similar to how a car's shock absorber woks (though there's no springs involved that return it to a given position). The movement is a bit slower because of this fluid moving back and forth, but bouncing up and down is also prevented, just like a shock absorber... It's not quite like the implement is just hanging out there on a chain or something and can move up and down totally freely -- but it can move up and down enough, fast enough, for most purposes....

Hope this added understanding rather than more confusion...

 

[toolz_not_toyz]

Awesome! Now I get it. /forums/images/graemlins/grin.gif

Thanks.

 

[tracdoc]

Operator just has to be watchful when using float with ground engaging tools. If the initial angle of "attack" into the ground is steep enough, the implement will want to dig itself to China /forums/images/graemlins/shocked.gif, even when the detent is set to float. The implement, locked into the ground, is basically controlling the now passive lift cylinders as Kent described. I found this when I reversed the tines on my 5' rake so I could rake going forward (it's a great tool going forward, especially now with tons of leaves /forums/images/graemlins/grin.gif. FOURTEEN also found it when he reversed the spade on his potato digger to go forward.

 

[MossRoad]

Yes. You have to watch all implements when going forward in float.

If you engage something imovable with the buckets while the joystick is in float, the unit will try to drive over the lift arms. This happens on any FEL on any tractor, not just the PT.

The mower will tilt forward, too, if the leading edge of it catches something like a root or rock. So, always best to proceed with caution and walk any areas that you haven't been into in a while, first, before mowing or brush hogging.