An engine must be capable of driving both pumps when those pumps are being asked to put out all they have. Since engines are only new until you start them up, you need to factor in a few extra hp above the known needs, to compensate for the wear and tear that takes place. As you pointed out, the best hydro pumps require 14 hp to power them successfully. The smallest engine used to power the hydraulic system in a Case GT was a 10 hp Kohler K. It has been said many times that the Case hydraulic system, as designed, can put 12 hp to whatever is hooked up to it. Logic would dictate that you cannot get 12 hp out of the hydraulic system unless you put at least 12 hp in at the front end. So.......if you need 12 hp to drive the Case hydraulic system and another 14 hp to drive the hydro pump, the math says 26 hp.
That's my story....... and I'm sticking to it.
A Massey 1655 or 1855 borders on the sub-CUT sector of the tractor market. Mechanical rear PTO shafts are few and far between in the world of garden tractors. If you want to make this argument, then shouldn't it be made with the average garden tractor in mind and not the creme of the crop? As for your system, I don't know all the uses you put it to. If it is primarily to power the FEL, then the 2 gallons of oil in the loader towers is fine. However, this discussion has focused on having a system that is equal to the Case GT. I suggest that you install a temperature gauge on your system and then hook up a Case rototiller to it. Go to a spot on your property where the lawn is covering virgin soil and begin to rototill that 40 ft x 50 ft area until you have reached the maximum depth capabilities of the tiller and have cross-tilled the area. Do this on a day where the ambient temp is at least 80 F.
Keep an eye on the temp gauge and your watch. Record how long it takes for the oil temp to hit 180 F, then 200 F and then 220 F or beyond. Once you exceed 200 F, you are now entering the territory where hoses begin to deteriorate and so does the oil. Rototilling is likely the toughest task that we ask garden tractors to perform as it calls for the maximum from the equipment used. The Case hydraulic system is constantly asked to put out full flow to the tiller motor at pressures that often range between 1600 psi and 2000 psi on a constant basis, depending upon ground conditions and travel speed etc. You just don't see happening with a FEL or other cylinder uses.
On the 3100 and 4100 series ALL HYDRAULIC series of Case tractors, the system was often required to power three hydraulic motors at the same time. One motor powered a 48" three bladed mower deck, the second motor powered the Hydra-Vac system that sucked the clippings from the deck and deposited them into a trailer and the third powered the tractor.
In my mind, that's the criteria for duplicating a system that is equivalent to what is available in a Case or Ingersoll tractor. Therefore, someone wanting to convert an existing hydrostatic drive tractor so that it will operate a hydraulic tiller is going to need
- a gear pump capable of 10 gpm @ 3600 rpm, 3000 PSI max pressure
- a six gallon hydraulic oil reservoir
- an oil cooler with 1/2" ports
- some sort of fan to move air over that cooler constantly
- a control valve with built-in relief and 1/2" ports everywhere
- s suitable method to couple the pump to engine
- 1/2" hoses and fittings to connect all the components
- high flow quick couplers to make it simple to connect attachments
What do you have to say about that, Bob? :smile1::smile1::smile1::smile1::smile1:
Well hydriv, you make a lot of excellent points, although I do question the basis of some of them. In particular is your horsepower requirements to operate a hydro and a hydraulic system need to be looked at a little more closely. I might point out that while the Sundstrand has the capability to soak up 14 hp, the actual possibility of that happening is very limited. That requires full throttle and full forward speed with a load that is well above what most would even think about.
I haven't used many implements on my tractors and from this lack of experience I can only think of one chore that could be accomplished while demanding max output capability from the transmission and
the hydraulic system at the same time and I very much doubt if anyone has had occassion to take on the task. High power demand implements are not normally used at max forward speed. I don't think even the venerable Case tiller could do its intended job at 4 - 5 mph. Since the speed must be reduced to get the best benefit from an implement, the horsepower needed to operate the hydro is also reduced. I seriously doubt that more than 4 or 5 hp would be needed to pull even a reverse cutting tiller leaving 11 - 12 hp for the hydraulic system.
That's my story.........
The first Case tractor that I met personally was a 666, or was it a 444? Anyway it was a small TLB that I saw on a road trip before I acquired my 1655 and I would place both firmly in the same class. That Case was my inspiration for putting a loader on my MF12H which belongs in the small GT
class. That little tractor with its 12 hp engine also had no problem dealing with an 8 gpm auxilliary hydraulic system. As you have stated, hydraulic motors require larger reservoirs and there were places on that particular tractor that could accomodate a substantial reservoir, if needed.
You seem to bypass the issue that with only one pump, the tractor drive is robbing power from the implement on a Case, whereas with two systems the full output of the auxilliary hydraulic system goes to the implement and anything left over from the engine can operate the more efficient hydro. It's all a matter of budget and balance with the edge going to the piston pump in a hydro.
Heat is the #1 killer of hydraulic systems and for motor work a cooler is always a good idea. As you pointed out , a FEL
is a limited load on a hydraulic system and my reservoirs have about 6 square feet of radiating surface for a mere 2 gallons of fluid. After extensive use for several hours of loader work on an 80* day, I could/can/did put my hand anywhere on either tank for more than 5 seconds without serious discomfort. That makes the oil temperature less than 120*, a long way away from the 275* point of oil breakdown. My heavy tractors are primarily snow movers and I have often thought of installing an oil cooller just for keeping me a little warmer even though neither system needs one at -20*.
- 10.75 gpm gear pump @4350 psi cont. - $214.99
- single spool valve with relief adj. to 3000 psi - $169.99
- 5 gal reservoir - $89.99
- Quick couplers- 2 sets - $40.96
- pump mount - $35 - $60 depending
Partial total $575.93 +/- Fast perusal of PAL catalogue..
Alternate sources can be utilized to reduce the cost. I live in a border town with access to the southern retailers and home made fabrication can cover other items for less. I have a pair of 10 gallon reservoirs that cost $5 for both at a local auction. I have no doubt that I could bring in such a project for under $800 using my trades skills and parts on hand. For someone without those skills or parts, but shopping wisely, $800 is not a lowball price. The toughest one is the oil cooler.
You forgot the motor. - 2.8 cid, 1800 psi - $249.99
There's one sitting on my shelf. But that does raise the price to over a grand.