Hydraulic motor and pump help

[Metalburner]

So engine size I'm looking at around a minimum of 688cc or so to make it work properly.

 

[aczlan]

I was going to ask if I should put a cooler in and possibly get a small electric pusher fan to help cool it even more. Looking at the motor it seems like the shaft has large splines on it. Not a problem, would just need to have the drive sprockets machined to fit it directly or find a hub that'll fit and bolt on that way.

I might look at mounting the pumps inboard and using a coupler to a solid shaft: 163-166 1" 6T COUPLING
Not sure on the fan, but to run much of one, you might need to add an alternator to have enough power as most pull 20+ amps.

Aaron Z

 

[Metalburner]

Engines I've been looking at have at least a 20amp stator which could work for that plus lighting. Or I could run a cooler and a gallon larger reservoir to help with cooling.

 

[MossRoad]

Our little PT425 has a 10 gallon oil tank and a large hydraulic cooler with electric fan, and it still gets quite hot.

 

[Metalburner]

How much hydraulic oil am I going to need? I know for the front loader and 3 point hitch, I'm looking at about 3 gallons, then probably another 4 gallons for the hydraulic wheel motors, so I'm guessing about 8-10 gallons needed as well?

 

[MossRoad]

That I can't help you with.

 

[Metalburner]

I'm coming up with a parts list for the mechanical and hydraulics needed, I know I'll be missing lines, but this should give me a visual of what I'm looking at and you guys can amend my list as you see fit.

1. Honda GX688 http://www.northerntool.com/shop/tools/product_200431124_200431124

2. 2 Hydraulic pumps 1.1 cu in WHITE HYD PISTON PUMP 11812

3. 2 Hydraulic Wheel motors 19.6 cu in WHITE DRIVE PRODUCTS 25532A631AAAAA HYDRAULIC MOTOR

4. 2 2" bore 18" stroke hydraulic welded cylinders 2x18x1.125 DA HYDRAULIC CYLINDER WOLVERINE WWCL218-S

5. 1 2" bore 6" stroke 3pt hitch cylinder 2x6x1.125 DA HYDRAULIC CYLINDER WOLVERINE WWCL26-S

6. 1 2" bore 14" stroke cylinder for bucket curl http://www.surpluscenter.com/Hydrau...C-CYLINDER-WOLVERINE-WWXT2014-S-9-8771-14.axd

7. 1 5.5gpm hydraulic pump for FEL and 3pt Hitch http://www.surpluscenter.com/Hydrau...cu-in-DYNAMIC-GPF1061PA-HYD-PUMP-9-7768-D.axd

Just have miscellaneous spool valves, hydraulic lines and fittings, 8 sprockets for #100 roller chain, unsure amount of feet of #100 roller chain (40'-80'), 14 smaller sprockets to act as bogies or tensioners for track, 25 various pillow block bearings for chain sprocket/pulleys. Hydraulic cooler, hydraulic oil filter(s). 10 1" solid steel axle shafts. 30' of 2x4x1/8 rectangle tubing, 20' 1x1x1/8 angle iron, 2 4'x8' expanded steel, 3 4'x8'x14ga sheets of sheet metal. Various sizes of grade 8 bolts.

 

[aczlan]

The general rule of thumb is 1 gallon of tank capacity for each 1 gpm of pump capacity. So the two pumps I linked to would need a combined 30 gallons of fluid.
That said, the above rule of thumb does not take into account hydraulic coolers, so you can add a cooler and greatly reduce the amount of fluid needed. I might order an all metal radiator for a compact car (say a Civic, those radiators can be found for cheap) that comes with a fan and adapt your return lines to run through that.
If you have a 1 1/4" inlet and outlet to the tank and are feeding that with a 1" return to tank line, pressure shouldn't be a problem.

Aaron Z

 

[oldnslo]

Metal burner,
Some things that you should take into consideration if you already haven't

1) Track size length and width. Turning a tracked vehicle is based on the ability to skid steer turn. I don't recall where or when I read the article but from memory but track length Vs width must be considered to facilitate turning. I.e. tracks with 6 ft ground contact 3 feet wide probably would not turn at all.

2) Torque required to turn: Tractive effort of 100% or more of gross vehicle weight is required for skid steer turns again depending on track design.

3) Yes an oil cooler must be used for any serious use of a hydrostatic transmission.

4) Closed loop control also requires removing some fluid from the closed loop and replacing it. On more expensive systems a flushing valve is incorporated into the motor and a charge pump is built into the pumps to provide the cooling and flushing flow.

5) Closed loop reservoir size will depend on heat load and cooler capacity. These are both challenging numbers to arrive at. Variable like duty cycle loads, ambient temp, cooler cleanliness, etc. all play a factor in this. General rule of thumb for systems is 25 - 30% of input power is what the cooler must remove. Some systems require more some less.

Not trying to discourage you just trying to get you thinking about the complete system Vs individual components.

 

[Metalburner]

Metal burner,
Some things that you should take into consideration if you already haven't

1) Track size length and width. Turning a tracked vehicle is based on the ability to skid steer turn. I don't recall where or when I read the article but from memory but track length Vs width must be considered to facilitate turning. I.e. tracks with 6 ft ground contact 3 feet wide probably would not turn at all.

2) Torque required to turn: Tractive effort of 100% or more of gross vehicle weight is required for skid steer turns again depending on track design.

3) Yes an oil cooler must be used for any serious use of a hydrostatic transmission.

4) Closed loop control also requires removing some fluid from the closed loop and replacing it. On more expensive systems a flushing valve is incorporated into the motor and a charge pump is built into the pumps to provide the cooling and flushing flow.

5) Closed loop reservoir size will depend on heat load and cooler capacity. These are both challenging numbers to arrive at. Variable like duty cycle loads, ambient temp, cooler cleanliness, etc. all play a factor in this. General rule of thumb for systems is 25 - 30% of input power is what the cooler must remove. Some systems require more some less.

Not trying to discourage you just trying to get you thinking about the complete system Vs individual components.

Track size is 6" wide and will have close to 36" for the length touch the ground. So for the hydraulic drive, I would need a separate reservoir for that?