Farmall M hydraulics question

[drglinski]

So someone before me plumbed up the hydraulics on this M with a 3 point.  I'm confused on how it behaves and was hoping someone could help explain it.  It has a M&W pump (which is awesome by the way, to have live hydraulics) using the belly pump location as a reservoir.   To raise the 3 point the inner rod is pulled back and the Christmas tree rod (outer) is pulled back.  To lower it you push the inner rod away from you (down) and pull the outer Christmas tree rod and it lowers (but only by gravity).  I had always thought that running hydraulics through the Christmas tree valve would make it double action power lift and power lower, also that it would be the sole operating rod in the system and not dual like mine is.  Furthermore, whatever implement I have on it (like a blade) it does not float.

 

Any insight is appreciated.  

 

 

[drglinski]

I meant to put this in the technical part of the forum.  

[766 Man]

  Going through the Christmas tree valve should give the same action whether through the live pump or belly pump.  The inner Lift All rod pulled out should give double acting function to the cylinder(s) assuming they are plumbed as such.  Possible the feed from the pump to the Lift All housing is not correctly hooked up but seems unlikely as you can lift the hitch.  The inner rod should be left pulled out and is the function of the clip that runs just under the rod on the rod support. 

[brahamfireman]

The inner rod is supposed to be locked back constantly.  You use the Christmas tree rod to power up and down. My only guess is somethings hooked up wrong.

No float with the Christmas tree valve that I'm aware of.

[Absent Minded Farmer]

1 hour ago, brahamfireman said:

No float with the Christmas tree valve that I'm aware of.

There isn't on my H that I know of either. If it does, it doesn't work.

Mike

[rustred]

12 minutes ago, Absent Minded Farmer said:

There isn't on my H that I know of either. If it does, it doesn't work.

Mike

nope no float. either go up or down.

[snoshoe]

The belly pump valve needs to be latched back. Then just use the Christmas tree valve to raise and lower. Pull to raise and push to lower. The single acting belly pump valve will provide float but you would have to plumb to it and latch Christmas tree valve to use.

It looks to me though that your hitch has a mechanical float by pulling two pins.

[drglinski]

8 hours ago, brahamfireman said:

The inner rod is supposed to be locked back constantly.  You use the Christmas tree rod to power up and down. My only guess is somethings hooked up wrong.

No float with the Christmas tree valve that I'm aware of.

Ok, yeah I'm aware how it's supposed to work, but for some reason that's now how this one behaves.   I can't get the double acting Christmas tree valve to move forward only back.   That's what made me think it was possibly plumbed wrong or something internal was different. 🤷

Thanks 

[drglinski]

17 hours ago, snoshoe said:

 

It looks to me though that your hitch has a mechanical float by pulling two pins.

That it does! Never saw that or investigated it before.  Thanks!

 

Upon further inspection it seems like the Christmas tree valve is restricted from going forward thereby not allowing it to have power lower (It's not the lockout latch).   I might have to disassemble the valve and see if it's hung up for some reason.  

[Binderoid]

I don't  understand why the belly pump is being used at all. Run the pressure line to valve and let it drain down  the filler neck. Remove the lever and plug  everything  coming  out of  the clutch housing. 

[snoshoe]

2 minutes ago, Binderoid said:

I don't  understand why the belly pump is being used at all. Run the pressure line to valve and let it drain down  the filler neck. Remove the lever and plug  everything  coming  out of  the clutch housing. 

Need to add a relief valve to do that. This system preserves the single action function and is the reason for the latch on the 2 way valve.

[Absent Minded Farmer]

22 hours ago, drglinski said:

So someone before me plumbed up the hydraulics on this M with a 3 point.  I'm confused on how it behaves and was hoping someone could help explain it.  It has a M&W pump (which is awesome by the way, to have live hydraulics) using the belly pump location as a reservoir.   To raise the 3 point the inner rod is pulled back and the Christmas tree rod (outer) is pulled back.  To lower it you push the inner rod away from you (down) and pull the outer Christmas tree rod and it lowers (but only by gravity).  I had always thought that running hydraulics through the Christmas tree valve would make it double action power lift and power lower, also that it would be the sole operating rod in the system and not dual like mine is.  Furthermore, whatever implement I have on it (like a blade) it does not float.

 

Any insight is appreciated.  

 

 

Forgot to add, that's a Saginaw 3PH, if it helps you any. They're quite heavy duty. Think the Cornhusker hitch is the only one heavier.

Mike

[drglinski]

45 minutes ago, Absent Minded Farmer said:

Forgot to add, that's a Saginaw 3PH, if it helps you any. They're quite heavy duty. Think the Cornhusker hitch is the only one heavier.

Mike

Yes it is, and I've used both....and they are both great hitches.  

[Binderoid]

3 hours ago, snoshoe said:

Need to add a relief valve to do that. This system preserves the single action function and is the reason for the latch on the 2 way valve.

Ah, yes I forgot the  relief valve. So, where is the pressure line going, into a port on the other side? 

[snoshoe]

5 minutes ago, Binderoid said:

Ah, yes I forgot the  relief valve. So, where is the pressure line going, into a port on the other side? 

Don't really know. Disappears behind suction line. Thinking it has to be ported into belly pump plate.

[Absent Minded Farmer]

2 hours ago, drglinski said:

Yes it is, and I've used both....and they are both great hitches.  

Is that a bucket nipple on the PTO? Not a bad idea.

Mike

[drglinski]

5 hours ago, Absent Minded Farmer said:

Is that a bucket nipple on the PTO? Not a bad idea.

Mike

It's on an overrunning clutch that I use with the rotary cutter that dad had- it was his setup and he always had it on there.  Not sure where it came from but it splined to match a PTO. 

[drglinski]

I took the top of the valve off today and was able to free the piece that has the nuts on it by spinning it separate of the spool but it still only moves on way.  Ruling out the nuts being off centered could it be seized up further in? Can I unscrew the tree valve to get it to clear the fuel tank so I can pull the spool and see what's up further in?

 

Thanks 

[snoshoe]

50 minutes ago, drglinski said:

I took the top of the valve off today and was able to free the piece that has the nuts on it by spinning it separate of the spool but it still only moves on way.  Ruling out the nuts being off centered could it be seized up further in? Can I unscrew the tree valve to get it to clear the fuel tank so I can pull the spool and see what's up further in?

 

Thanks 

If you have the top off. You should be free of the tank bracket. Loosen the union by the fill pipe. If there is enough slack in the hoses you should be able to tip it forward. Otherwise the control rod, four hoses and the union and remove it.

[drglinski]

So I was able to remove the valve but the rod inside the valve only moves the one way (out) and  I don't understand what's restricting it from going the other direction (in).  What am I doing wrong?  Is it supposed to insert further into the valve? Is it centered incorrectly with the double nuts? It moves freely in the valve with the cap removed.  

 

Thanks 

[drglinski]

I was able to get the spring out to try to clean it up and get it functional.......now it seems like the spring isn't doing anything to help center the valve in the body, and it still won't go into the power up down position.  Does the spring have a snap ring to hold it in the valve? If it did that's gone now.... For something that is seemingly so simple it's been a huge headache of trial and error trying to learn how it works with little to no information online about it ....and I'm about at my wits end.  🤷

[snoshoe]

Remembering practically nothing of the interior of that valve but noticing from your pictures that lever is hinged in front of spool. Since pulling rod raises. That means spool down is up. Evidently you have full travel in that direction. Pushing rod forward is lower which should raise spool up. Seems up is where your failure is. With apparently nothing to hold that spring assembly in the spool. I suspect that is where the problem lies. Do we have a parts breakdown on here?

[drglinski]

Yes, correct.  Spool goes down just fine into assembly but I can't get it to raise to run power "down.".  Or is it not centered correctly in the assembly and already at full travel in that position? Are the spring spacers in the correct location up/down on the threaded rod? I've got the parts catalog and it seems simple enough but not a service manual (if one exists). 

 

In getting the spring out I damaged the snap ring.  Where can I find another one of those? 

[snoshoe]

I suspect 2 is stuck inside 3 preventing the rod from moving down. However I haven't figured how that is your problem yet but needs to be fixed.

If that spring was not bottomed in the spool. The spool is probably positioned to low on the rod and the rod hits the cap. Get that apart and cleaned up along with inside of spool. Reassemble and adjust until it just allows the snap ring to enter groove. Measure bore of spool for snapring size. Should be able to obtain at a hardware store.

[drglinski]

#2 and #3 are suppose to move independently of each other? Those two on the bottom of the spring were in really rough rusty shape.