return line plumbing problem

[Chaostamer]

I have a Mahindra 3215 and plan to put a Shaver #8 post driver/pounder on it. In doing so, I need to get a 3/4 to 1" hose to drain back to the tranny. The problem is I don't know where. I have one idea - take it back to the transmission oil fill hole. The problem is I don't know what the thread and size is of the fill hole. I took the cap to a hydraulics place today and they said they had no idea what the threads were. Here are my two questions: 1) does anyone know what that threading is and how I can get a fitting for it? and 2) does anyone have an alternative idea on plumbing it back into the transmission? It MUST be 3/4 or 1" size (i.e. running back to the pump or the drain plug will not work). Any ideas are welcome! And thanks in advance for any help!

 

[jenkinsph]

I had the same questions for a return to tank line on my Deere 4520 and plan to use the location where the optional hydraulic fluid heater is installed. I did not want to use the transmission filler because the fluid being returned would be above the level of the transmission fluid. This would cause bubbles and air entrainment in the fluid. You need the return to be lower than the level of the fluid in the transmission case. Another member who had this issue was able to run a tube through the filler neck and devised a way to seal it off. That would depend on how your tractor is designed and what might be in the way.

If it were me I would ask your Mahindra mechanic if he has a solution. Brian (Moutain View Ranch) has Mahindra tractors and may have a better idea for you. I would not bother asking this of the sales staff, most times they would not have a clue.

Don't expect very many responses on this.

 

[Chaostamer]

...I did not want to use the transmission filler because the fluid being returned would be above the level of the transmission fluid. This would cause bubbles and air entrainment in the fluid. You need the return to be lower than the level of the fluid in the transmission case.

jenkinsph - Thanks for the comments. I understand your note quoted above. Seems like there are several opinions on this one. I have come to the conclusion that you are right, but if you cannot get the return below the fluid level (and there is very limited places to get a 3/4' line tied in), the top fill is an acceptable alternative (just not ideal). The guy I bought my used pounder from has installed several and runs about 4-5 miles of fence using his own unit and he fills into the fill plug. I will follow up with Brian if I can figure out how to contact him.

 

[boggen]

*rubs chin* hhmmsss if you have a rear hydraulic remote, or a FEL (front end loader), just plumb it into the rear remote or one of the FEL bucket or FEL arms, and just hold the joystick / lever all the way in one direction.

if need to put a bungie cord or something to hold joystick / lever in given direction.

hydraulic valves. work by only putting pressure to one side of a hydraulic cylinder or hydraulic pump. and the other side goes directly to tank.

there is no "suction" power like a vacuum in hydraulics on a tractor. it just goes straight to tank.

also, hydraulic oil generally has its own pump and tank up in front of the tractor. and rarely ever comes from the transmission.

on other hand transmission and 3pt hitch raising/lowering might be tied together. more so on SCUTS (sub compact utilty tractors) BUT that is only for raising and lowering 3pt hitch, the rear remotes and FEL should have a single hydraulic pump and tank. separate from transmission.

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as long as you have correct valves smaller tractors generally have "open center" valve setup. on larger tractors you might have "closed center" valve setup. as long as you have open center valve setup. you should be completely fine.

 

[Catoosa]

My ford 3000 has a loader ran off the tractor hydraulics, little slow but works for me, return line is in the fill cap. Bought a spare cap to play with, drilled and taped it for 3/4 pipe, used a short nipple and a T. Ran the return into the side of the T and put a pipe plug in the top so I could add fluid without having to disconnect anything. You can get 3/4 pipe nuts and short nipples in the electrical dpt of the Big Box stores. Return line is low pressure, normal plumbing hardware will work fine.