Aaargh! 3-pt hitch not lifting any weight.

   / Aaargh! 3-pt hitch not lifting any weight. #81  
Is there anyway you can plug all the holes and hold you finger over where 13 goes and get some pressure to one of the #20 plugs?
 
   / Aaargh! 3-pt hitch not lifting any weight.
  • Thread Starter
#82  
Is there anyway you can plug all the holes and hold you finger over where 13 goes and get some pressure to one of the #20 plugs?

i don't think that will plug enough of the holes, just about every hole connects to an adjacent chamber....
 
   / Aaargh! 3-pt hitch not lifting any weight. #83  
I see. At doing that you would have to make a plate and over the 3 mounting holes. When I said plugging the holes I forgot about them. I did mean plugging without the guts.
What I'm about to say now. Don't do this until the very last thing and there is nothing else someone might come up with. Very carefully dill a small hole in it, if it doesn't turn. Just deep enough that you can start a tap in it about 3 or4 threads then pull. I'm talking a #6 or 8 tap and if you can get one or 2 threads then grind the point off and you can then get 2 or 3 more.
 
   / Aaargh! 3-pt hitch not lifting any weight.
  • Thread Starter
#84  
I see. At doing that you would have to make a plate and over the 3 mounting holes. When I said plugging the holes I forgot about them. I did mean plugging without the guts.
What I'm about to say now. Don't do this until the very last thing and there is nothing else someone might come up with. Very carefully dill a small hole in it, if it doesn't turn. Just deep enough that you can start a tap in it about 3 or4 threads then pull. I'm talking a #6 or 8 tap and if you can get one or 2 threads then grind the point off and you can then get 2 or 3 more.

i gave that some thought, I also thought about gluing something to face to pull it out
 
   / Aaargh! 3-pt hitch not lifting any weight. #85  
I'm going to sleep a little more on this. If I wakeup around 4am I'll call you right away before I forget it. Later
 
   / Aaargh! 3-pt hitch not lifting any weight. #86  
careful application of heat and cold? Perhaps freeze the entire assembly then heat the outside?
 
   / Aaargh! 3-pt hitch not lifting any weight. #87  
If it is steel, have you tried one of those little magnets on a pen to help pull it out. Spray some lube on the part and wait a little while, then stick the magnet and pull.
 
   / Aaargh! 3-pt hitch not lifting any weight.
  • Thread Starter
#88  
It is fixed!!!!

It was too stuck to use a magnet.
I managed to get the allen key into one of the holes in 8 thru an adjacent channel. I put the entire length of the allen key into the bench vise and pulled. The o-ring was broken (I'll post some pictures later tonight) and the part that fell off was stuck in the valve.

I reassembled the entire valve and put the assembly back in to the tractor and my initial tests (1000rpm, with me standing on the arms lifted with out a problem. Tomorrow I will put everything back together and try to lift something heavy.....
 
   / Aaargh! 3-pt hitch not lifting any weight. #89  
You got it!!!!!!!!!!!:cool2::cool2::cool2::cool2:
 
   / Aaargh! 3-pt hitch not lifting any weight. #90  
Sweet! congratulations. That was one for the record books.
 
   / Aaargh! 3-pt hitch not lifting any weight.
  • Thread Starter
#91  
Here are some pictures of the damaged part (the slit in the o-ring was to get it off)
DSC_0508.JPG


DSC_0510.JPG
 
   / Aaargh! 3-pt hitch not lifting any weight. #92  
The parts that were stuck in the assembly, was that the flow control for the 3pt valve or the valve that controls the descent rate?
 
   / Aaargh! 3-pt hitch not lifting any weight.
  • Thread Starter
#93  
It is part of the 3pt hitch valve, it's called the flow control valve. I haven't figured out exactly how it works in the valves function.
 
   / Aaargh! 3-pt hitch not lifting any weight. #94  
When you screw in the knob for the 3pt lock, are those parts involved?

I am guessing that the valve got stuck in the valve housing, and blocked the flow into the 3pt cyl.

In post #68, upper right, that appears to be the 3pt spool, so it looks like the other parts should be the flow control for the descent valve
 
   / Aaargh! 3-pt hitch not lifting any weight. #95  
That part he is showing is just a plug and when it was put together the oring got cut and just now broke all the way loose, then got stuck in the little spool.
 
   / Aaargh! 3-pt hitch not lifting any weight. #96  
The flow control valve appears to be spring loaded, and I can almost bet that the end of the screw, presses on this part to push in on the valve and regulate and close off the flow to the 3pt. The o-ring is there to seal off the fluid.

My thoughts on the 3pt valve is this. The 3pt lever controls the amount of fluid going into the 3pt cyl, and the flow control valve controls how much is allowed to flow out of the cyl.

If the flow control valve is closed, will the 3pt lever allow the 3pt to operate at all or just one time, to raise the 3pt, but not lower until the knob releases the fluid.

{ Response control. Response control (in most systems we know of) simply serves to control the rate at which hydraulic oil is allowed to escape from the lift cylinder. By slowing this rate, we minimize undesirable oscillations that would otherwise occur. Response control has no effect on rate of lift, and that is good, because we want the plow to raise quickly when we hit a hard spot. However, if we let the plow go back into the ground at an uncontrolled speed, we will end up pulling a plow that jumps into and out of the ground. We have to give the system a little time to settle down somewhere in the raise/lower cycle, and that is the function of the response control.

If lower is selected, the oil from the pump is directed, by the control valve, to the reservoir (just like neutral); however, a passage is also opened which will allow oil to escape from the lift cylinder, allowing gravity to lower the lift arms. Many of the smaller compact tractors are, in fact, just that simple in lift control. }

Any other thoughts on this?
 
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   / Aaargh! 3-pt hitch not lifting any weight. #97  
( The flow control valve appears to be spring loaded, and I can almost bet that the end of the screw, presses on this part to push in on the valve and regulate and close off the flow to the 3pt. The o-ring is there to seal off the fluid. )




I think hyd oil moves that spool open and closed. What screw are you taking about? If you mean the push pin that goes into another hole altogether.


( { Response control. Response control (in most systems we know of) simply serves to control the rate at which hydraulic oil is allowed to escape from the lift cylinder. By slowing this rate, we minimize undesirable oscillations that would otherwise occur. Response control has no effect on rate of lift, and that is good, because we want the plow to raise quickly when we hit a hard spot. However, if we let the plow go back into the ground at an uncontrolled speed, we will end up pulling a plow that jumps into and out of the ground. We have to give the system a little time to settle down somewhere in the raise/lower cycle, and that is the function of the response control. )

Where did you find this or can you put the link to it? I would like to read all of it, if there is more to read.
 
   / Aaargh! 3-pt hitch not lifting any weight.
  • Thread Starter
#99  
The knob that screws in to regulate descent does not physically touch the control valve, it is physically in front of the center of the cylinder.

I think leejohn's explanation of the part is correct.
 
   / Aaargh! 3-pt hitch not lifting any weight. #100  
1st thanks for the link JJ. After reading it I understand it more. The way I see how it works is, the response control valve (spool) is always working and it shines if you have draft control. By just slowing down a load and the knob on the rockshaft lets you over ride it. Now I can see why if the spool is open (with part of the broken oring) the 3pt would not lift.
 

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