Mower deck hydraulic motor.

[Mith]

I'm wondering if anyone would be able/willing to read the specs off the motor on their rotary mower, or finishing mower and post them for me.
I'm thinking about building a hydraulic mower deck for my tractor, and I'd like to have an idea of what displacement motors are being used on something that works already. Trying to figure out the necessary torque for a mower is quite tricky.

I have scratch-built a tractor similar to the power-trac, being that it is all hydraulic I dont have a standard PTO, hence the need for a hydraulic run mower.

Thanks.

[SnowRidge]

Mith, there are several different motors on the various PT mowers. Not too long ago I did all the research necessary to replace the deck mounted motor on my PT-425's brush cutter. It wasn't easy, as Power Trac often deliberately obliterates the motor data plate. I'm on the road at the moment, so I don't have access to the motor information, but it is roughly 50cc.

Can you tell us the max flow and pressures of your system? That way the folks with equivalent or close PTs can respond.

[Mith]

Snowridge, I'd appreciate that when you can.

As to flow and pressure, I'll just add another pump so thats pretty flexible.
Looking for maybe 5' width, but I'd also be interested in the motor specs for any of the mowers. As long as I know the machine that the motor is used with I can figure out what I need to know, and just scale it up or down depending on the application.

I'd like to make both a normal mower, and a boom mower would be nice too. So any and all information is appreciated.

[SnowRidge]

OK, I'll dig up the numbers when I get back in a few days. I'm sure others will be posting, too.

[3238dpw]

OK MITH this is very important.

WE NEED PICTURES OF YOUR MACHINE

[Mith]

You can read the story on the build here
It isnt done yet, but it works. I'm still in the playing with the new toy stage, another couple months maybe I'll do the bodywork.
I suppose in terms of operation its very similar to the PT. I've got a 3pt linkage on the back though instead of the PTs loader.

[duane]

I believe the finish mower decks for the 400 series use a Gresen high speed motor made by Parker; model number MGG20025, diplacement is 0.58 cu in/rev rated at 9.88 horsepower continously, and 12.4 horsepower intermittently. If you search the Power Trac forum, I think you may find it.

[Mith]

Thanks Duane. That motor is much smaller that I was anticipating.

I did a search, but I didnt find anything. I'll give it another shot and see what comes up.

[Bob999]

I don't profess to be an expert on this matter but if I were to try to reverse engineer a solution I would start out with the hydraulic power available on various units--which are designed for varying size of mower. The 422/25 series is approximately a 4' mower. The 1430 is approximately a 5' mower. The 1845 runs a 6' mower---etc. You indicated you are thinking of a 5' mower so I would use the hydraulic power for the 1430 and identify a pump that could be installed on your unit that will produce the PTO hydraulic power of the 1430.

Most mowers in this size range use at least 2 blades and 6' mowers typically use 3 blades so direct drive is not a practical option--rather belt drives are used and that introduces the option to run the blades at a speed other than the motor speed. Selection of blade speed is a function of the size of the blade because blade tip speed is the design criteria. Once you know the desired tip speed, the effective gearing between the hydraulic motor and the blade, and the hydraulic flow you can select the displacement of the hydraulic motor. The motor selected will need to be capable of handling the max pressure available.

[KentT]

Good advice, Bob999...

The PT-425's drive a 5' finish mower, BTW, but only a 4' rough-cut mower. The PT-422 has a 4' finish mower available, or you could try the 5' -- but it would likely not perform too well in tall, damp grass.

On those class machines, the 60" finish mower is a 3-spindle, belt-driven design, while the 48" rough-cut mowers have a single stump-jumper spindle, directly connected (my older design has a lovejoy connector though the newer designs are different). Not sure how the 48" finish mower is designed...

Here's a pic of the motor mounting and belt routing on the 60" finish mower:

http://mypowertrac.com/DesktopModule...om&ImageSize=5