3-Point Hitch 3 point hitch won't lift

[sevans]

Thanks,

Yes, the owners manual says different fluid for front versus transmission. Only thing I can think of is that the transmission was overfilled because I got nearly 8 gallons when I drained it. The manual says 27.5 quarts so it must have been overfilled by at least a gallon.

I don't have the owner's manual but will have today. From your pdf I found that the dip stick should not be screwed in to check the level.

I found another very minor leak on the rigid pipe shown below. The NH site had a detail of this section and it doesn't show an o-ring but only a "fitting assembly" but I'm pretty sure there ought to be an o-ring in there. I'm going to replace this o-ring, providing there is one, and the 2 on the outlet pipe I sucked the oil from. I'll let you know how it goes and thanks again for the help and all the great resources.

Then I may give the tractor a good bath!

 

[JC-jetro]

Thanks,


I found another very minor leak on the rigid pipe shown below. The NH site had a detail of this section and it doesn't show an o-ring but only a "fitting assembly" but I'm pretty sure there ought to be an o-ring in there. I'm going to replace this o-ring, providing there is one, and the 2 on the outlet pipe I sucked the oil from. I'll let you know how it goes and thanks again for the help and all the great resources.

Then I may give the tractor a good bath!
View attachment 108414

Sevan,
The hyd elbow is JIC fitting where it is connected to the rear diffy housing. it is tapered, if it leaks there it might be a bit loose. The other side of the elbow is compression fitting and may or may not have an oring. I guess it does not have an oring and might have a ferrule or flared. Some may like to put Teflon tape on the threaded part but not all approve it as it might get in to hyd spool causing problem. Since this connection is pre-filter before any control valve I think it'll be okay. I will not go heavy on teflon and make sure wrap the threaded part counter clockwise and not leave anything loose hanging from the end. before any dis assembly I get a crescent or open end box wrench on the outer nut and tighten it a bit to see if that makes any difference.

JC,

 

[sevans]

After cleaning it up I found it is leaking from the connection to the rigid pipe and not where the fitting screws into the oil sump housing. Even as weathered as it is I believe I do see remanants of teflon tape on the fitting. I'll try tightening the pipe connection first.

Well... I put new hyd fluid in and replaced the filter but it did NOTchange the 3 pt lift problem.

I guess I'll start looking at the list of possible causes as shown on p. 95 of the repair manual posted eariler.

Thanks,

 

[JC-jetro]

After cleaning it up I found it is leaking from the connection to the rigid pipe and not where the fitting screws into the oil sump housing. Even as weathered as it is I believe I do see remanants of teflon tape on the fitting. I'll try tightening the pipe connection first.

Well... I put new hyd fluid in and replaced the filter but it did NOTchange the 3 pt lift problem.

I guess I'll start looking at the list of possible causes as shown on p. 95 of the repair manual posted eariler.

Thanks,

Need to establish flow first. If you do not hear grinding and cavitation noise pump is probably okay since you had leak under pressure (on the discharge side of the pump). The most likely scenario is Hyd cylinder piston seal. Not difficult at all in your tractor. re check the thread I made to replace mine, should have ample info and pics there to help.

JC,

 

[sevans]

It's a rainy day here is North Central Texas... I'll listen for noise but I sure don't remember hearing any. Great observation about the leak on the discharge side.

Are you referring to the 'lift cylinder' piston seal?

When I recieved the operator's manual I was suprised to find the IT FO-44 Shop Manual. I believe you have the same manual so the lift cylinder piston seal (#25 below) is shown on page 99 and attached here.

 

[JC-jetro]

It's a rainy day here is North Central Texas... I'll listen for noise but I sure don't remember hearing any. Great observation about the leak on the discharge side.

Are you referring to the 'lift cylinder' piston seal?

When I recieved the operator's manual I was suprised to find the IT FO-44 Shop Manual. I believe you have the same manual so the lift cylinder piston seal (#25 below) is shown on page 99 and attached here.

View attachment 108452

Yes. Yes, it is the seal. Take a note that part #'s on FO-44 may not be the same as NH site. The seal is right but it is actually numbered #19 on NH website rather than #25. Must use/buy the following. Take a look at the lip orientation on the seal, it is a one time deal, can not remove the new seal without damage to it if installed incorrectly.

19 1 SBA050309012 Seal Seal, Start Year: 01/01/1983

JC,


Old damaged seal:




New seal install:

 

[sevans]

YIKES! You said it isn't difficult...

It is done from the front side by removing the cylinder head but the lift arms and shaft must be romoved? Once the shaft is removed first then everything from #13 through #19 (NH numbers) ought to come out the front side, is this correct?

Thanks for the pics. It's difficult for me to envision the job from a figure in a book.

It looks like I'll need to replace about a dozen o-rings and a 'dealer-ordered' seal.

 

[JC-jetro]

YIKES! You said it isn't difficult...

It is done from the front side by removing the cylinder head but the lift arms and shaft must be romoved? Once the shaft is removed first then everything from #13 through #19 (NH numbers) ought to come out the front side, is this correct?

Thanks for the pics. It's difficult for me to envision the job from a figure in a book.

It looks like I'll need to replace about a dozen o-rings and a 'dealer-ordered' seal.

It ain't exactly a piece of cake you know... But if I can do it, I guarantee you lots of people can do it a swell.

yes, it is all done from front. That's pretty easy. the cylinder has two big o-ring (nothing you can find from HF oring set). I changed mine but really there was nothing wrong with them. I save the old one for spare.
You might need a few o-rings , buy Harbor freight metric set @ $10 and you're good to go.

JC,

Put the cylinder and head together and put it in as a whole assembly.

You can withdraw cyl head, cylinder and piston. Cylinder head is attached/sealed to the cylinder by way of big o-rings (two), just pull them apart, comes apart easy.

You see the ram rod that cuases rotational movement of rock shaft leading to 3-pt arm to raise. Hyd lift spool on the left side of the pic.

 

[sevans]

I can probably do this better than baking a cake.

From your pics there's no need to remove the lift arms so the job doesn't look too stressful.

I found the seal here locally for about $15 and they're holding one for me. The big o-rings don't look like anything my local ACE Hardware stocks so I'll pick them up from the NH dealer as well.

Habor freight metric set? Is that a set of o-rings or tools. If it's tools, I have a full compliment of metric wrenches and sockets (and breaker bars).

Again... the pics are fantastic and very much appreciated.

 

[JC-jetro]

I can probably do this better than baking a cake.

From your pics there's no need to remove the lift arms so the job doesn't look too stressful.

I found the seal here locally for about $15 and they're holding one for me. The big o-rings don't look like anything my local ACE Hardware stocks so I'll pick them up from the NH dealer as well.

Habor freight metric set? Is that a set of o-rings or tools. If it's tools, I have a full compliment of metric wrenches and sockets (and breaker bars).

Again... the pics are fantastic and very much appreciated.

No lift arm removal, big o-ring from NH ( doubt if you need to change them), HF metric set is referred to o-ring set, You'll find 90% of what you need from the set and at least 10 of them in each set. I bought 3 oring from NH costing more than a HF set.

You're welcome

Jc,

 

[sevans]

Timing couldn't be better... I was on my way to NH when your post came over my blackberry. I didn't buy the 0-rings but priced them at about $16 for the pair.

I took the piston out and found the seal looks new. Here's a pic.



I'm going to put it back together with the original seal (since it doesn't look anything like your failed one) and try something else. Any suggestions?

 

[dqdave1]

I hope the dial to regulate the speed of the 3 point was turned down all the way; this can cause it to not lift.

 

[JC-jetro]

I'm going to put it back together with the original seal (since it doesn't look anything like your failed one) and try something else. Any suggestions?

Okay Sevan, Let's have another stab at it.

You fixed the leaks, filter change and you put new Hyd fluid in and still no go.
We need to establish to see if we have flow and then if that flow get to hyd lift piston. You can remove the banjo connection on the discharge and run start the tractor with an assistant taking a bucket to catch the oil coming out. with that you can measure flow but not the pressure. it is a good test but I don't recommend it because it does not reveal what the lift control spool valve is doing. I'd check the system on the discharge size of the spool valve. Your hyd system is open center configuration, just simply if your spool valve handle on the 3-point is all the way down, cause all the flow to go thru spool valve back to hyd reservoir in the diffy housing. As you raise the 3 point level part of the flow goes to lift system and the rest to the diffy. When the spool is at it's highest point then all the flow is directed to the piston till the arm is risen to its highest point and then all the flow is returned to diffy housing. Attempting to raise the 3 point higher and you cause the safety relief valve to release causing a chattering noise.

Look the pic below, This the inside look at you lift cyl head head. You see four holes,
1st from the right with the oring is hyd oil discharge coming from the spool valve.
2nd from the right is the rate of drop needle valve, providing some flow as well to lift move the piston.
3rd from the right is normal flow from the spool to raise the 3 point arm. The opening only allows flow toward piston only becuase it has a ball check valve.
4th hole is open to the diffy to allow for oil release when the lift is under shock loading. This hole is also served by a very stiff spring and a ball check.

What you see here is two check valves in the lift head. The first with the big ball is for normal flow to the piston and second is a safety relief. The key is to remember is " a completely closed rate of drop knob" can only keep the arm from dropping but you can still raise the arm if it is half way provided you have flow.

What I would do take the nut off as shown in picture, and start the engine with an assitant to catch the flow. I'd make sure the lift spool is in closed position. At this time you should have no flow coming out, as you raise the lift spool handle to raise the implemnt flow should start. if you do not have fllow then either your spool is bad or your pump not flowing. Rate of drop has no role whatsoever here.

By the way if the pump is operational and spool is bad and you get no flow coming from the piston head then all flow must be diverted to the diffy reservoir.

All of that said, likelihood of bad spool valve is minimal and I thinks we're closing in on bad pump or main pressure relief valve is stuck open before any flow to the spool valve as pictured below.

JC,

 

[JC-jetro]

I hope the dial to regulate the speed of the 3 point was turned down all the way; this can cause it to not lift.

I don't believe this is a true statement with 1710 or many other tractors. Rate of return needle valve is not the only passage way for fluid to lift the lift piston. The second hole has a check valve that allow only flow to the piston and not other way. Partially closing the valve and you can limit return flow. But if the knob is all the way closed and the lift arm is in the middle or all the way in the bottom you can still raise the arm, and once you archive max height withe the knob closed then you can not lower the arm until you open the needle valve.

JC<

 

[sevans]

Thanks again!

I did check the rise in the full range of flow from the regualting knob and got nothing.

This sounds like a good test. From FO-44 pg 95, if there is flow as I raise the lever then we're looking at: 1) an adjustment to the linkage or relief valve pressure; 2) faulty o-ring in several places; 3) faulty safety relief valve; or 4) plugged suction filter. However, I can't find where a suction filter is used on the 1710; I checked the NH website and searched for 'filter' under the 1710 catagory.

FO-44 doesn't mention a faulty check valve as a possible cause. Is there a reason a bad (or stuck) check valve wouldn't cause my problem?

I plan to take out the valve assy. and inspec all the parts and run the test here in about an hour or two.

By the way, the post hole digger and subsequently the 3 pt is UP and held up with a cable hoist. Does this matter?

 

[Bedlam]

Thanks for the pictures there is beauty inside a tractor.Al tho i have a newer model ford, I think it would be the same or similar setup, Always wondered just what on inside there.
I saved the pics for future reference.
Thanks Again

 

[JC-jetro]

Thanks again!

I did check the rise in the full range of flow from the regualting knob and got nothing.

This sounds like a good test. From FO-44 pg 95, if there is flow as I raise the lever then we're looking at: 1) an adjustment to the linkage or relief valve pressure; 2) faulty o-ring in several places; 3) faulty safety relief valve; or 4) plugged suction filter. However, I can't find where a suction filter is used on the 1710; I checked the NH website and searched for 'filter' under the 1710 catagory.

FO-44 doesn't mention a faulty check valve as a possible cause. Is there a reason a bad (or stuck) check valve wouldn't cause my problem?

I plan to take out the valve assy. and inspec all the parts and run the test here in about an hour or two.

By the way, the post hole digger and subsequently the 3 pt is UP and held up with a cable hoist. Does this matter?

I'd be very careful with the valve assembly as the tolerances are very tight. I'd eliminate all possibilities before going there. No issue I see with the Post hole digger being held up. If main pressure relief is stuck open due to contaminant can cause flow diverted to the sump but possibly a percentage of it and not all. You have not established pump flow yet and manipulating rate of return knob provides no good information. let's make sure you have solid flow out of the pump yet.

JC<

 

[sevans]

Sorry JC... I didn't mean "check valve" when I said there is no mention of it causing the problem.

What I meant was 'needle valve' in the cylinder head or anything else wrong with the cylinder head like a plugged hole.

YES!!! the pictures are great and very helpful.

 

[JC-jetro]

Thanks for the pictures there is beauty inside a tractor.Al tho i have a newer model ford, I think it would be the same or similar setup, Always wondered just what on inside there.
I saved the pics for future reference.
Thanks Again

My pleasure, all Ford/shibuara Sp? are designed the same. It is really a very impressive and simple design. Even Kubotas are not as well designed and much disassembly is required to get to the guts of lift system. I really did not have good clue what I was buying, but I'm very pleased after I got to learn the design of it.

JC,

 

[sevans]

I guess I'm confussed... Isn't the valve assembly what you've pictured with the springs and ball bearings? More importantly, isn't this what I'm supposed to take out to run the test for flow?

Or am I supposed to take out the plug on the opposite side to test the flow. I believe this plug is where a pressure tester is screwed in so I'm somwhat hesitant to have it open with maybe 2200 psi hyd fluid shooting at me.

Thanks,

Scott