MF 30 Industrial Hydraulic quit. please help

Hello all.
My MF 30 Industrial's hydraulics just quit. I was digging with the backhoe under normal conditions, and all of a sudden I just felt the pressure quit in the controls. Nothing hydraulic would work any more. I didn't see any major leaks (I have a few small leaks that I have had a while, but nothing major). I don't know a lot about hydraulics, but could anyone point me in a direction of what I could check?
Thanks!
 
The crankshaft driven hydraulic pump coupler could be your likely culprit. If you remove the pump from it's mounted position and check the inner splines on the driveshaft and the pump shaft outer splines, all may be revealed, good luck & let us know how you go with it, Evan.
 
(quoted from post at 07:54:29 04/19/18) The crankshaft driven hydraulic pump coupler could be your likely culprit. If you remove the pump from it's mounted position and check the inner splines on the driveshaft and the pump shaft outer splines, all may be revealed, good luck & let us know how you go with it, Evan.



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Pump lost connection or no fluid, , if its internal pump, could be pto clutch . Just guessing! Hope it's not to bad a fix.
 
(quoted from post at 09:05:21 04/19/18)
(quoted from post at 07:54:29 04/19/18) The crankshaft driven hydraulic pump coupler could be your likely culprit. If you remove the pump from it's mounted position and check the inner splines on the driveshaft and the pump shaft outer splines, all may be revealed, good luck & let us know how you go with it, Evan.



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Ok. Yall were spot on. BUT... shaft and coupler are both stripped out. My problem is im nit sure how the coupler comes off. I hace the pump side iff. The shaft just pulled out if coupler. However, the coupler is still on shaft from other side. Please tell me it comes off and isnt made on tobthe shaft?

Thanks!
 
I have tried to get this coupler out by driving something up in it and hitting it (clockwise) to get the shaft to turn out of the crank? Is this correct?

Also, when it would grab, it would turn the crank over too. How do you keep the crank from turning over? The splines are stripped in the coupler so I cant get another shaft up in there to weld something to it. IDEAS!!?!? Thanks!
 

The shaft is threaded into the crank adapter with reverse thread. So turning it to the right, (clockwise) will loosen it. It may take a little heat to loosen it up, but watch you don't destroy the bushings if they're still good.

I used a chain wrench/strap wrench to keep the crank from turning. I also put the machine in high range, third gear, and blocked the rear wheels just in case.
 
Thanks! How are you getting to the threads to hear them up. I can barely see the shaft in on little hole. I can’t see where the threads are entering the crank adapter..... unless I’m missing something which is very possible.

Thanks!
 
The shaft uses left hand threads so it will tighten under a loader rather than unscrewing itself which would be bad. So the threads on the drive shaft going into the coupler will be super tight. You could try to block the rear wheels, set the parking brake, and put the tractor in gear to keep the crankshaft from wanting to turn (if it has hand fuel shut off to kill the engine put it in the kill position just in case). On some I've had to cut the shaft off at the coupler, replaced the coupler also because it was just so stuck, especially the rubber bushings in the coupler are gone which usually egg shapes the holes for the bushings.
 

So, I'm a little confused. You cut the coupler off and then welded a new one to the shaft because you couldn't unscrew the shaft?
Thanks!
 
I cut the shaft off close to the coupler so I can unbolt the coupler from the crankshaft, and remove the coupler (you can't get the coupler off the crankshaft with the entire shaft still in the coupler).
 
(quoted from post at 10:06:04 04/26/18) I cut the shaft off close to the coupler so I can unbolt the coupler from the crankshaft, and remove the coupler (you can't get the coupler off the crankshaft with the entire shaft still in the coupler).

So you are calling the piece to the far left in the picture you sent the “coupler”. I’ve been thinking number 21 was the coupler. Sorry i’m A little slow.
Thanks so much for the help!
 
(quoted from post at 08:50:02 04/26/18) Thanks! How are you getting to the threads to hear them up. I can barely see the shaft in on little hole. I can’t see where the threads are entering the crank adapter..... unless I’m missing something which is very possible.

Thanks!

I'm assuming you meant heat them up. I ran my torch over the adapter plate that bolts to the crank. I didn't go crazy, just got it good and warm. I heated up around the center "nipple" of #18.

#20 screws into #18 with left handed thread, so to loosen it, you need to hold 20 still, and turn 18 clockwise as you look at it from the FRONT of the machine.

I used a chain wrench around the crank pulley to keep it still, heated up the area AROUND where 18 threads into 20, and used another strap wrench to turn 18.

My machine is from '64, lived a tough life, I got it off. It was a pain in the butt! I ended up replacing everything from crank adapter up to the pump.
 
On the last couple that I did I had to replace the crank adaptor because it was run so long without the bushings it egg shaped the bushing holes out. One got ran for so long without bushings that it broke out a couple of the threaded holes in the crank pulley (which means I had to remove the front axle support to get the crank pulley out, what a pain).
 

Ok, thanks for all of the help!! I was able to get that shaft unscrewed, but I'm sure I did it pretty unconventionally. The splines on the coupler and the splines on the shaft of the motor were stripped out. I was unable to find where you could buy another shaft for the motor either. It looks like you have to just replace with an aftermarket pump?
Anyway, because I figured I would be replacing everything anyway, I took a solid metal bar and welded a nut on one end. Then, I grinded the other end to a taper. I pushed the tapered side up inside the coupler and then welded it to outside lip of the coupler. I put a pull handle on the welded nut and someone else pushed the fan belt in to keep the crank from turning. I hit the pull handle with a hammer. After about three hits, It popped loose.

Once I got everything out, I got to looking at it. I thought because the pump was still good that I would try to "rig" it up before I go and spend $700-800 on a new pump and coupler/shaft I'm going to try and make this work.

So, this is what I came up with. I cut a slot in the splinned shaft off the hydraulic pump. I also cut a slot in the coupler I cut a piece of metal to run through the coupler and will slide into the splined shaft. I welded it on the outside to the coupler. It fit very snug.

My plan is to screw the coupler and shaft back in. The splined shaft will now just slide into the coupler and the piece of metal will serve as a keyway of sorts. Not sure how well this will work, but thought I would give it a shot. I may be crazy but oh well. What's my problem going to be?

Thanks!!

mvphoto15763.jpg


mvphoto15764.jpg


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Should you need the parts to fix it.
Part # 707166M92 Shaft Assembly, Pump Drive
Part # 190496M3 Coupler

What pump you need depends on the loader model number.
MF 32 loader
Part # 708483M91 Pump Assembly (Hydreco 20 G.P.M.).
Part # 708502M91 Pump Assembly, Hydraulic (Hydreco) (17 G.P.M.) Used with oil filter.

MF 34 loader
Part # 708502M91 Pump Assembly, Hydraulic (Hydreco) (17 G.P.M) Used with oil filter.
Part # 709351M91 HYDRAULIC PUMP (USED W/MF 30 AND MF 3165 W/OIL COOLER).
Part # 709351M91 Pump Assembly (24 G.P.M.) (Vickers #G20-6F-15S-11A 11L) 1-5/16" - 12 Inlet Port And 1-1/16" Outlet Port.
Part # 708996M92 Pump Assembly (24 G.P.M.) (Vickers #G20-6T-15K-11A 11L) 1-7/8" - 12 Inlet Port And 1-5/16" - 12 Outlet Port.
 

If it makes you feel any better, my pump is not a spline fit like yours. Mine is a simple keyway that stops the pump from slipping on the shaft.

Your fix has a good chance of getting you buy indefinitely.

Might be a good time to drain/refill the hydraulic oil for the loader if it's got it's own reservoir. Water in there can freeze up in the winter and wreak havoc on the system. Ask me how I know. :(
 

Thanks that does make me feel better about the fix.

Thanks for all of your help PT!

I did get it all mounted back up and it works. I haven’t really put the pump under a strain, but I will.... hopefully it will last me for a while. If not I will let y’all know.

Thanks again.
 
The coupler for my front mount hydraulic pump uses a woodruff keyed oil pump, the other end of the coupler is welded to the drive shaft that screws into the crank adaptor.
 
(quoted from post at 16:03:19 04/30/18) The coupler for my front mount hydraulic pump uses a woodruff keyed oil pump, the other end of the coupler is welded to the drive shaft that screws into the crank adaptor.

Exactly how mine is. I replaced the whole setup because:

A) it was cob jobbed from the last owner and the pump was mounted on the OUTSIDE of the loader frame making it vulnerable to rocks rolling back and hitting it.

B) there was a small 4-bolt coupler that connected the pump to a separate extension to get it to "work"

C) the aforementioned ice in my hydraulic oil. (I'm assuming this)- I fired up the machine on a 3* day and the moment I touched the controls, the cobbed shaft disintegrated. Right before a monster storm in April when I needed it most!

Anyway, here's my new setup before install:


mvphoto15776.jpg
 
That's exactly how mine is.

You don't happen to be Kenneth S. from TBN, do you? The nature of your posts reminds me very much of him, always a huge help. :)

If so, your comments were instrumental in my decision to buy my 35 Utility.
 
(quoted from post at 05:17:11 05/01/18)
That's exactly how mine is.

You don't happen to be Kenneth S. from TBN, do you? The nature of your posts reminds me very much of him, always a huge help. :)

If so, your comments were instrumental in my decision to buy my 35 Utility.


That would be me.
 
(quoted from post at 13:47:21 04/30/18)
(quoted from post at 13:10:36 04/30/18)
Anyway, here's my new setup before install:

mvphoto15776.jpg




That's exactly how mine is.

Reviving this old thread. In hopes of more help. @ptfarmer, My "rigging" decided it was time to break. The slot cut and entered in the shaft lasted a couple good years, but it has broken. Now, I am having issues trying to get the coupler (part that screws in to the crank adapter) out. There is no splines left on anything, and I can't get to the end to weld anything on to be able to turn the coupler/shaft.

What all has to come off to be able to access the coupler/Shaft enough to get a pipe wrench or something on it? The part I am trying to remove is part number 20 in the diagram you provided. I had it off previously by welding something to the end of the coupler that I could turn, but there isn't enough to weld to now. Any ideas/help?

Thanks!
 

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