It's not about boring me nor is it about purism. If you wish to modify a red tractor, then go ahead. There are still plenty of red tractors around. I agree with your assessment regarding the costing of the parts. Valves for hydraulics are not inexpensive. Therefore, careful planning is needed and that is what rockdog and me have been expressing. In addition, there is precious little room on these tractors to mount extra valves and to run hoses or lines in a way that they won't be problematic in one fashion or the other.
Let me break this down for you.
GOING FASTER TO CUT GRASS.
Click on this link .
http://www.manuals.casecoltingersoll.co ... marked.pdf
Then scroll down to a bit better than halfway through the book and you will find an exploded diagram of the trans-axle. Look at iTEM 25 and then refer to the next page for the parts index. You will see that Ingersoll offered two different tooth counts for the high range gear. To purchase that gear from Ingersoll would cost you more than $300.00. However, 4000 series tractors are being parted out these days and I have seen the complete trans-axle sell for less than $100.00. Swapping out the trans-axle is a one day task, at best. I suggest that you contract our keystone member Bob MacGregor about this gear because he has first-hand knowledge about the benefits. The Low Range gear remains the same. Therefore, nothing will change when it comes to the so-called "overloads" you say that you inflict on your tractor.
SIMPLE FACT
The Case Hy-driv system is what it is. You can stick a big block rat motor under the hood and feed it NOX all day long but you won't see more than 14 HP being delivered to the rear wheels. I can't make it any clearer than that. Every component was selected to work in harmony as a unit. When you make changes that go outside the parameters of the original system design, then you will find yourself in trouble of one kind or another. Yes. there are some mods that can be done. Few of them represent "low cost". You are playing with a tractor that has a current replacement cost that is close to ten grand. If you want low costs, then choose a tractor that had a low price tag when it was new. If you want to play with a Rolls-Royce, then expect to pay Rolls-Royce prices.
Hydraulics is a science about pressure and flow. It has rules. That's why there are people with the title "Hydraulic Engineer". These people know the rules and respect the rules. I am not an engineer but I do know about several of the rules. I also know about what others have tried with these tractors and failed at. I'm trying to pass some of that on to you in this thread and so is Rockdog.
So let's back up here and look at this again.
EXTRA CIRCUITS
In order to not re-invent the wheel here, how about this? As I understand it, you essentially want the ability to control THREE different low pressure circuits that would operate small cylinders. You could do that by installing a small electrically operated valve bank with three spools. You would disconnect the mid-lift cylinder from the travel/lift spool. The lift spool would be disconnected mechanically from the lift lever beside the steering wheel. Remove the lift lever from the tractor. You would then lock the lift spool in the "full lift" position so that it constantly delivers flow out one port. That port would be connected to the IN port of the valve bank. The OUT port of the valve bank would then return to the other work port on the lift valve.
If you do that, you then have a three bank valve that can deliver low flow oil to a max of 575 PSI unless you alter the relief setting in the lift valve one way or the other. A gauge plus trial and error would allow you to fine tune the best setting. Any of the spools on the valve bank can be fitted with "float" to restore that feature to the mid-lift cylinder. Weather resistant bat handle switches could be mounted in a convenient spot to control the valve bank and it could be mounted under the tractor to keep all the lines out of sight.
If you want a rear PTO, then that would be plumbed into the system as I described earlier. It would not be connected to this valve bank circuit in any way. There would be no need to get into Power Beyond or Flow Control Valves. If you still desire Power Steering, then stick with method selected by the engineers. Use a priority valve and a slightly larger pump to provide the flow needed for the PS without compromising the rest of the system. If you do it this way, you will not throw the system out of balance. You will not create extra heat. You will keep your costs reasonably low.
Yes.... John Deere was putting remotes on their tractors many years ago but there isn't a Deere GT made that can power hydraulic motors. Yes, they can make small cylinders go in and out but that's it. I am not dissing Deere. I am simply pointing out the major difference in the two systems.
If you are having problems with rototilling, then you need to do some investigation into why. What I find curious about new owners of these tractors is this. They buy a well-used Case or Ingersoll tractor for ten cents on the dollar and expect it to function like a new one. Do these people not understand the concept known as "wear and tear"? Every part on their tractor has undergone wear and tear. It is a credit to the overall strength of the design that these tractors are worth repairing. The major parts are nearly bullet proof. There are very few problems with the frames, front axles or trans-axles. The drive motors have incredible life and the travel/lift valves rarely need attention. Coolers are excellent and so are the reservoirs. Pumps are a different story. They definitely wear and over time, they stop delivering their rated pressure and flow. Fortunately, they are relatively inexpensive to buy but some owners are aghast at having to fork out $250.00 for a replacement. Really? Try buying a replacement hydro pump for a Wheelhorse or a Deere. You won't touch one for less than triple that figure.
Your turn.