Ford 1720 3 point lift problem. I need your HELP!

[JC-jetro]

I did try what BuzzardA19 recommended and tried turning the knob (that sets the speed at which the 3PH raises and lowers), this is not a true statement, the knob only helps with the rate of drop in and out several times to see if that made a difference. It did not. I still do not have any lift. I do still have my front hydraulics working on my loader though so the pump must be working. I don't have a pressure gauge to try what was suggested. In my shop manual it states:

The following are symptoms which may occur during operation of the hydraulic lift system and their possible causes. Use this information with TESTING and ADJUSTMENT information when diagnosing hydraulic lift problems.


Admittedly I do not know much about hydraulics so any advice would be appreciated. Has anyone had this model of tractor and had similar problems? All thoughts would be helpful. Thanks

I did also suggest to take the the nut off where the I put the gauge per pic on previous post. This will be somewhat messy if you have flow but takes nothing to do it. Need to have a helper to shut the engine off quickly. Don't try to block the flow with your finger as it will not work and will be dangerous. To avoid oil spill I try to put a temp elbow there and re-direct the flow using a hose in to a bucket.

Going back to the manual and their recommendation.

1. Hitch will not lift load. Could be caused by:
a. Restricted hydraulic oil filter.

If you had that your loader would not work either
b. Linkage out of adjustment or broken.
Possibility but doubt it as the are built pretty beefy. A quick look at the linkages to see if they have come apart might not be a bad idea
c. System relief valve pressure setting too low.
slight possibility, can not see it change all of the sudden unless you have some derbies blocking the port or broken spring. It is unlikely as you have hyd pump and loader working.
d. Safety relief valve faulty.
On their own, they very seldom fail due to robust design. Not too difficult to check.
e. "O" ring failure between control valve and valve cover.
very slight possibility in my opinion
f. Oil leakage past lift cylinder piston seal.
I give this the highest possibility and the best "bad outcome", that 's why I suggested you check pressure or flow. Once you know that it will help quite a bit. A question here, can you lift the arm without any load on 3 point?, if so , then raise the 3 point all the way and then turn the rate of drop knob clockwise to completely closed position and watch the arm on how quickly it comes down. That'll be your proof positive that is the seal.
g. Oil leakage pas lowering valve poppet.
This would be the last thing I will ever dork with, you need to take seat off, and diffy cover just to see the spool valve. The spools and poppet are high quality machined part that by inspection only you'll find nothing. It take a lot of experience and 9.9 out of 10 they work flawlessly for the life of the tractor.

Check the flow thing and report back. By the way a gauge from is easily enough available for not much money. certainly excellent tool to have in the tool box.

JC,


Valley Instrument Hydraulic Pressure Gauge Liquid Filled, 5000 PSI | Filled Gauges| Northern Tool + Equipment

 

[Hooked_on_HP]

How are your remotes operated. If electricly could the solinoid be stuck.
Bill

 

[OldBulldogger]

Thanks for everyone's help and advice thus far. I did visually inspect all external linkages last night and everything appears intact and as it should be. I fired up the tractor briefly last night and the front loader is working still as it should. I have enough pressure to lift the front of the tractor off the ground so I am thinking I did not damage the pump when it got hot. What do you think?

JC, I did what you suggested and manually raised the 3 pt arms without any load on the three point. Before starting the tractor, I manually raised them and they immediately fell. Without the tractor running, I did the same thing again only this time when they were raised, I turned the rate drop knob all the way in to the closed position and they still fell back down immediately. I then repeated the exact process again only this time with the tractor running and again when they were raised, I turned the rate drop knob all the way in to the closed position and they still fell back down immediately. I also visually inspected the remote hydraulics valve assembly and when I move the lever, I can see the valve going in and coming back out in both directions and always returning to the middle position on its own. So, does this sound like oil leakage past lift cylinder piston seal?? If so, what actually went wrong and what causes a failure?

On a side note, I did not have a remote hydraulic setup when I bought the tractor. I found a factory used one for sale on ebay and bought it. It was the original Ford remote kit that you could purchase as a kit and add to these tractors. It came with 4 new "O" rings however only three fit as one was too big so I did borrow a ring out of the old cover during assembly. After assembly, all worked well and as it should the first time I had to use it to blow snow. I use the remote to hydraulically turn the blower chute which really does not require much pressure. This was only the second time using the blower since our last big snowfall. The only thing I did not care for when using the remote the cylinder on the blower is that it was hard to feather the control and sometimes the cylinder seemed to really ram hard one direction or the other when trying to use it. So, from the shop manual I have it lists one of the possible causes to the problem I am having is "O" ring failure between control valve and valve cover. If I had a failure there, would I notice hydro fluid leaking out or could the "O" ring fail internally and cause this? I am just trying to cover all bases and when I inspected it visually I do not see any external seepage. One thought I had was to remove the remote hydraulics I had added and just put only the cover back on as it was before and try it to see what happens. My thinking is that I could try to eliminate that as a cause of this problem. It would be easy enough to do. Any thoughts about that?

Lastly, one fellow I talked to said to verify if the remote valve is sticking I should reverse the hydraulic hoses on my blower chute to see if the tractor now pulls the cylinder back the other direction. I did do that and the cylinder did not move at all. So does that eliminate the remote hydraulics valve as a cause?

Thanks for all the advice everyone and please keep the thoughts coming.

 

[JC-jetro]

JC, I did what you suggested and manually raised the 3 pt arms without any load on the three point. Before starting the tractor, I manually raised them and they immediately fell. Without the tractor running, I did the same thing again only this time when they were raised, I turned the rate drop knob all the way in to the closed position and they still fell back down immediately. I then repeated the exact process again only this time with the tractor running and again when they were raised, I turned the rate drop knob all the way in to the closed position and they still fell back down immediately. I also visually inspected the remote hydraulics valve assembly and when I move the lever, I can see the valve going in and coming back out in both directions and always returning to the middle position on its own. So, does this sound like oil leakage past lift cylinder piston seal?? If so, what actually went wrong and what causes a failure?

Gene,

I think we're gaining on it. So just to be sure tractor was able to raise the arm without any load on them? Right? if so then you lift spool valve is working like it should, and you have flow to the 3 point. Now one more question , when you raised the 3 point while tractor running could you maintain the arm position constantly? if so I think we are closed to the right diagnosis. you have a major leak at the lift piston seal but the rate of leakage is less than what hyd pump can deliver so the lift stays up, with the tractor off when you close the rate of drop all the way the trapped oil leaks out and the arms drop. I think with the rate of drop knob closed but tractor running you still should be able to keep the arm up with no load on the tractor, is that the case?

I think you got a $10 seal to replace and you'll be good to go. I don't know how much sheet metal you need to remove to have access to the lift head right under your seat. On my 1700 it was very easy as I had to just take out 6 bolts and I was there. look at the link below on how I did mine.

JC,

http://www.tractorbynet.com/forums/...ng/90819-my-f-1700-testing-my.html?highlight=

 

[OldBulldogger]

JC, thanks for all the help. Just to clarify, the tractor will NOT lift the three point arms on its own at all - load or no load. I had to physically raise the arms with my hands, hold them up, and then have someone turn the rate drop knob to close. I did this with the tractor off and then also when it was running and in both cases, as soon as I let go of the arms with my hands, the arms would immediately drop back down within seconds.

Does this indicate a lift spool valve not working like it should, and that I have no flow to the 3 point?

Thanks!

 

[JC-jetro]

JC, thanks for all the help. Just to clarify, the tractor will NOT lift the three point arms on its own at all - load or no load. I had to physically raise the arms with my hands, hold them up, and then have someone turn the rate drop knob to close. I did this with the tractor off and then also when it was running and in both cases, as soon as I let go of the arms with my hands, the arms would immediately drop back down within seconds.

Does this indicate a lift spool valve not working like it should, and that I have no flow to the 3 point?

Thanks!

That was what I was afraid off. if you had any flow and the cylinder was flooded with oil then closing rate of drop would not allow you to raise or lower the arms by hand. If you had flow then you piston seal must be totally gone not to provide slightest resistance. At this point I think the easiest way and least intrusive would be to take the nut off where you I had the gauge. if you have flow then I'd say it is the seal. if no flow then it might be on hyd block, lift spool and more difficult things to fix.

I wish you had a gauge to if your had pressure without making a mess.

Let us know.

JC,

 

[Hooked_on_HP]

JC , I am pretty sure that manualy lifting the tph arms doesn't move the lift cyl. piston. Ther fore lifting the arms and closing the drop rate knob wouldn't prove any thing.
Gene, If you still have the origional parts I would remove the remotes you installed and put it back to the way it was origionally and see if cures the problem.
Bill

 

[JC-jetro]

JC , I am pretty sure that manualy lifting the tph arms doesn't move the lift cyl. piston. Ther fore lifting the arms and closing the drop rate knob wouldn't prove any thing.
Gene, If you still have the origional parts I would remove the remotes you installed and put it back to the way it was origionally and see if cures the problem.
Bill

Bill,

You are right that lifting arm manually would not lift the piston, but if piston holding and seal is good, then manually you can not push the arm down because of trapped fluid. My suggestion was to somehow by the action of the lift mechanism raise the arm and then close the rate of drop knob to trap the liquid in the cylinder to get clues about seal. I still think flow or pressure or better both needs to be proved. f the ram rod, pin was damaged trying to lift he arm manually might also give some clue to damage.

JC,

 

[OldBulldogger]

JC, I did pick up a hydraulic pressure guage this afternoon so my plan this weekend is to see if I am getting any oil in the tractor lift cylinder area. I have a 1720 model and I think in your photo you had a 1700 model. Are they the same setup? If they use the same part here then from what you said I should see on the right side of lift piston head a square head nut. If I take the nut off then that is were I would attach the gauge, correct? I assume just like in your photo. The gauge I have is liq filled , between 0-5000 psi. It was all they had on hand. That should work I assume. Basically I am trying to see if have any pressure going to the lift cylinder right?

If there is pressure reading on the gauge then the the lift cylinder seal is bad. If no pressure, then I need to look elsewhere. I think you said if there is no flow then it might be on hyd block, lift spool and more difficult things to fix. What did you mean by more difficult things?

Is the lift spool the control valve assembly where the lift lever I use to raise the arms is attached to? Also, I am going to remove the remote I added and put the cover back on as it was before the remote was added just to try to isolate if it is in the remote or not. I wasn't much of a job to put it on so I will also try that. Am I on the right track here?

Lastly, when I started the tractor up the other night, I do have enough pressure from the pump to raise the front end of the tractor off the ground with the loader. Can I assume my pump is working as it should?

Thanks for all your help and for everyone who has contributed to this post!

 

[JC-jetro]

J

Thanks for all your help and for everyone who has contributed to this post!

Okay Gene, I'll try to explain below.


C, I did pick up a hydraulic pressure guage this afternoon so my plan this weekend is to see if I am getting any oil in the tractor lift cylinder area. I have a 1720 model and I think in your photo you had a 1700 model. Are they the same setup? If they use the same part here then from what you said I should see on the right side of lift piston head a square head nut. If I take the nut off then that is were I would attach the gauge, correct? I assume just like in your photo. The gauge I have is liq filled , between 0-5000 psi. It was all they had on hand. That should work I assume. Basically I am trying to see if have any pressure going to the lift cylinder right?

Yes, the set up on the lift cylinder is the same on all shibuara/ford tractor. Look at the attached pdf for the head assembly. you take plug #4 off to put the pressure gauge just the same I have done on my 1700. 0-3000 would have been slightly more sensitive as you will not exceed 2300 psi for your rig, nothing to worry about. yes, but pressure does not always translate to flow. You can same pressure let say on 1/8" dia line or 3" dia, given same pressure the flow is significantly more in the bigger line. If you have flow but a very big leak at the seal the pressure will be low but not zero.

If there is pressure reading on the gauge then the the lift cylinder seal is bad. If no pressure, then I need to look elsewhere. I think you said if there is no flow then it might be on hyd block, lift spool and more difficult things to fix. What did you mean by more difficult things?

Yes, report the pressure reading and we go from that. Bad seal and you read less or less depending to amount of the leak. If no pressure I then would take the gauge out and start the tractor to see flow. You might push some crud out and a gush of oil or no oil at all. No oil at all then some place oil is blocked to diverted. Access to other components are more difficult as you have to take diffy housing cover off. I was limited on how much attachment I could add here.

Spool is inside of the cover, no easy access.

Is the lift spool the control valve assembly where the lift lever I use to raise the arms is attached to? Also, I am going to remove the remote I added and put the cover back on as it was before the remote was added just to try to isolate if it is in the remote or not. I wasn't much of a job to put it on so I will also try that. Am I on the right track here?

You are, but since it worked before I don't think there is any advantage y taking off just now. Let see if we have flow first. if we don't then you should do what you suggests. Look at the pic above, spool is under cover. picture shows the innards after I took the lift cylinder head off.,

Lastly, when I started the tractor up the other night, I do have enough pressure from the pump to raise the front end of the tractor off the ground with the loader. Can I assume my pump is working as it should?
yes, that is is indeed you have not have major damage to hyd pump. I know your pump is not a "tandem hyd pump" , basically two pumps and one common input shaft. You have one pump that does the 3-point and loader combined by some priority set up, I think 3 point is the priority and then the loader. Not 100% sure on 1720 as I don't have a loader on my 1700.

I hope you have some pressure reading there as tell tale sign of flow. By the way, taking the cover off and inspecting the cylinder and lift piston should not be difficult and that for sure shows a bad seal. Have gone thru the repair on the link provided?

JC,


ps. Look at the pic for the gauge. The gauge connection 1/4, you need to put an adapter to connect. I don't know from top of my head but I think it was 1/4" to 3/8". something like below.
http://www.amazon.com/Parker-Fitting-Reducing-Bushing-Female/dp/B000FN1MY0/ref=pd_sim_indust_6