JD 1530 _ FEL & 3pt issue

[cjburke42]

I have a JD 1530 that was inherited. It had a 48 series FEL [front end loader], but has never worked.
I am trying to get it functional before hay season arrives in TN.
Currently the 3pt works great no matter how heavy the attachment is. When I connect the lines to the FEL (supply line tees into line after the pressure control valve, return is plumbed into transmission housing top right above ankle.) The FEL shutters to raise and if any attachment is on the 3pt it fails to raise unless I max out a cylinder on the FEL and hold it (bucket or arms).
I also have a ported filter cover coming next week to see if this helps any at all. Just having a hard time processing what could be causing the 3pt issues after the FEL is attached.
I will 1st try removing the FEL valve return hose from tractor & with both FEL hyd control levers in neutral and see if any fluid comes out.

 

[Zebrafive]

Does the loader have any quick couplers? If so check they are properly coupled.
Other things to check:
Oil level
Sump screen
Transmission filter
Filter bypass valve (might be stuck open)

 

[rScotty]

I have a JD 1530 that was inherited. It had a 48 series FEL [front end loader], but has never worked.
I am trying to get it functional before hay season arrives in TN.
Currently the 3pt works great no matter how heavy the attachment is. When I connect the lines to the FEL (supply line tees into line after the pressure control valve, return is plumbed into transmission housing top right above ankle.) The FEL shutters to raise and if any attachment is on the 3pt it fails to raise unless I max out a cylinder on the FEL and hold it (bucket or arms).
I also have a ported filter cover coming next week to see if this helps any at all. Just having a hard time processing what could be causing the 3pt issues after the FEL is attached.
I will 1st try removing the FEL valve return hose from tractor & with both FEL hyd control levers in neutral and see if any fluid comes out.

How do you know that the 48 loader and control valves all work? Did it ever work with your 1530? Or is it untested?
If hooking it up like you describe causes the 3pt not to work unless the loader is stalled, that's a pretty good clue.

My best guess from what you are saying is that the 48 loader control valve isn't set up with the proper internal plug for use with a closed center hydraulic system like the 1530s have. You may be able to buy a plug, but if not you may have to buy a 2 spool loader control valve that has the convertible plug for closed center operation. That would be the first place I would look. Especially if the 48 loader came off another tractor that might have had open center hydraulics.

You can get an idea of 2 spool directional control valve prices at surpluscenter.com/hydraulics/

Good luck with the haying. Does your 1530 have the optional power steering - I hope?

rScotty

 

[cjburke42]

It does have PS. Before I got this deep into it, I took the valve off to the local hydraulic shop and told them something was not right so they applied 3000psi and tested it and said it is functional maybe my lines were hooked up backwards. From there went back home and double checked line connections and still have an issue. Guess I could have told them it is closed center if I knew tht back then

 

[cjburke42]

Does the loader have any quick couplers? If so check they are properly coupled.
Other things to check:
Oil level
Sump screen
Transmission filter
Filter bypass valve (might be stuck open)

Ok I'll check the bypass valve tomorrow

 

[rScotty]

It does have PS. Before I got this deep into it, I took the valve off to the local hydraulic shop and told them something was not right so they applied 3000psi and tested it and said it is functional maybe my lines were hooked up backwards. From there went back home and double checked line connections and still have an issue. Guess I could have told them it is closed center if I knew tht back then

They would have known if the valve was open or closed center type when they put it on their flow stand. But they might not have said anything because the way flow stands work the valve is going to test the same either way.

"Open" versus "Closed" systems mean just what they say, i.e, in neutral center position the Open system control valve is normally open to allow flow directly back to the reservoir because the constant displacement hydraulic pump is always putting out the same flow and pressure and the constant flow just goes around in a circle from pump to valve to reservoir back to the pump until you block the flow and divert some of the blocked flow to do something like work a cylinder.

Or in the case of a closed center system the control valve blocks the flow when it is positioned in the neutral center position. In that case the return goes to the accumulator rather than back to the reservoir. As the accumulator becomes charged up, it sends a signal to the variable displacement hydraulic pump to reduce flow and pressure. The closed system only pumps more fluid when it sees a drop in the pressure of the stored fluid in the accumulator.

Are you sure that when your loader valve is plumbed right internally and hooked up to allow the accumulator circuit to build pressure? And not just returning straight back to the reservoir?
rScotty

 

[cjburke42]

Fluid does come out of the return hose when I start the tractor with the control valves in neutral position. Looks like I am set up on open center

 

[rScotty]

Fluid does come out of the return hose when I start the tractor with the control valves in neutral position. Looks like I am set up on open center

OK, either that or else the accumulator isn't charged up. You may want to check your plumbing against a hydraulic schematic.

But with any luck you have now found the problem. It will be nice if the fix turns out to be as simple as making a change to the FEL control valve.
Next step is to determine the manufacturer of the FEL control valve and see if they make a closed center conversion plug for it.
rScotty

 

[Tx Jim]

Fluid does come out of the return hose when I start the tractor with the control valves in neutral position. Looks like I am set up on open center

If your control valve resembles valve in photo check for failed seal(item 10).

I still remember locating that same seal that had failed on a tractor with a model 48 loader that I was attempting to diagnose a hyd problem about 50 yrs ago

 

[Tx Jim]

OK, either that or else the accumulator isn't charged up. You may want to check your plumbing against a hydraulic schematic.
rScotty

There is no factory hyd oil accumulator on a JD 1530 hyd system to become discharged.

 

[rScotty]

If your control valve resembles valve in photo check for failed seal(item 10).

I still remember locating that same seal that had failed on a tractor with a model 48 loader that I was attempting to diagnose a hyd problem about 50 yrs ago

Yes, I agree with that. It might be that he has the correct control valve for the closed hydraulic system and it has a failed seal. But I would have thought that the hydraulic shop he took it to would have caught that with the test they did.
rScotty

 

[rScotty]

There is no factory hyd oil accumulator on a JD 1530 hyd system to become discharged.

That's curious....no acccumulator? What does it use instead? A closed center system has to have something performing the accumulator function to tell the variable flow pump to back off on the pressure when it is dead-headed. Of course I could be wrong about his 1530 having a closed center hydraulic system. I don't have a hydraulic schematic for his 1530 or any 1530 for that matter. I'm just relying on a couple of reference books that say the 1530 has a closed center system, and on the fact that JD's closed center system is pretty standard. TractorData.com also says closed center.

Then again, this is a pretty old tractor. Things could have been changed. While it is just about impossible to convert an open center hydraulic system to closed center, it should be possible to go the other way. I've never done it, but I'll bet someone has somewhere along the line. Done right, it could be a money saver on hydraulic system repairs....
rScotty

 

[Tx Jim]

Scotty
Yes JD 1530 has CC hyd system.. JD closed center hyd systems from '65-'92 are very similar in operation. The stroke-control valve in the frt hyd pump controls pressure. When stand-by pressure reaches set pressure of 2250 psi for majority of models the oil pressure inside hyd piston pump crankcase forces pistons away from rotating pump shaft which causes pump to cease pumping oil. Pressure is trapped in lines. When pressure falls below the "set pressure" springs forces pistons down against the rotating shaft & oil pumping commences. Check out the thread below as it has some utility oil schematics. I've witnessed open center valves installed on CC systems which causes poor hyd performance but I've never seen anyone try to convert a CC system to OC system or vice-versa. I'm not understanding your thought of how changing CC to OC could save $$$$ because not all control valves are convertible from one type to the other & hyd pumps are totally different.
https://www.tractorbynet.com/forums...5618-john-deere-1640-strange-hydraulic-2.html

 

[rScotty]

Scotty
Yes JD 1530 has CC hyd system.. JD closed center hyd systems from '65-'92 are very similar in operation. The stroke-control valve in the frt hyd pump controls pressure. When stand-by pressure reaches set pressure of 2250 psi for majority of models the oil pressure inside hyd piston pump crankcase forces pistons away from rotating pump shaft which causes pump to cease pumping oil. Pressure is trapped in lines. When pressure falls below the "set pressure" springs forces pistons down against the rotating shaft & oil pumping commences. Check out the thread below as it has some utility oil schematics. I've witnessed open center valves installed on CC systems which causes poor hyd performance but I've never seen anyone try to convert a CC system to OC system or vice-versa. I'm not understanding your thought of how changing CC to OC could save $$$$ because not all control valves are convertible from one type to the other & hyd pumps are totally different.
https://www.tractorbynet.com/forums...5618-john-deere-1640-strange-hydraulic-2.html

OK. Glad to hear that all the 1530 had a CC hyd. system. So we haven't been spinning our wheels here advising the OP. The info is all valid.

I didn't know that JD stored their pressure in the elasticity of the lines instead of in an accumulator. I am curious what you think of doing it that way. For my part I'd say that using line elasticity will work, although a more formal accumulator might still be added.

Do you agree that if there is an OC control valve on the 48 loader that it could be causing all the symptoms the OP reported?

As for converting CC to OC, this is something that used to come up in mechanical bull and beer after work sessions back when they were in person rather than online - that all seems a thousand years ago now with the virus. As I said, I don't think anyone ever actually did it. I never did.

Basically the point is that if the "set pressure" of a CC pump is somehow locked so that the variable pum always runs at full capacity, then it is behaving just like a constant volume pump in an OC system. We were not talking about changing the pump itself. Just the way it works....how to make a CC pump work like an OC constant volume type. A person might concievably want to do so if their expensive variable flow pump wore so much that the pistons and wobble plate were stuck in the wide open flow condition. The idea being that an OC control valve (or just the conversion plug) might be a cheaper fix in that case than a variable volume pump replacement. I agree that would be difficult to impossible to pull the pump itself and try to replace it with another type. But there would be no need to change the pump, as by preventing the pump from changing to the no-flow condition it has become an OC pump.

I guess that the point of the bull session is that by locking the set point to full "ON" a CC pump can be made to work like an OC pump, but there is no similar way to make an OC pump reduce its output like a CC pump can. Also that CC pumps are WAY more expensive than OC pumps.

Hey, thanks for the references. I'll look them up.
rScotty

 

[cjburke42]

Took the valve out.
It appears to be the correct one only missing most of the oring.
Now I will have to wait until Tuesday to go to hydraulic shop after the holiday unless Oreilly would carry a square oring box.
John Deere can get the part but its not in stock.

 

[Tx Jim]

Yepper reminds me of a similar failed o-ring I finally located many yrs back when I first started diagnosing closed center hyd system problems. Replace that seal with a good seal & you'll be amazed how much better your tractors hyd system will operate.

United Ag & Turf in Magnolia Ar. shows to have 3 ea-U30255 in stock

 

[Tx Jim]

Scotty
I still think from diagnosing hyd problems on CC hyd systems for yrs it wouldn't be ""easy or cheap"" to change from CC to OC or vice-versa.

 

[rScotty]

Scotty
I still think from diagnosing hyd problems on CC hyd systems for yrs it wouldn't be ""easy or cheap"" to change from CC to OC or vice-versa.

Congrats to CJ for taking the valve out and having a look. It's amazing what you can find by taking something apart.

Yes, Jim. I agree. The change is mostly interesting because it just might be possible. The special case where it might be worth doing would be where a very expensive variable volume pump had a mechanical failure of some kind that caused it not to be able to move its wobble plate & pistons to "full off".

There's a good reason why we only see Closed Center systems on the more expensive and sophisticated machinery. Open Center isn't better, but it gets the nod when the goal is less expensive & simpler. So OC is what is used for most homeowner and small Ag machines.

Obviously the goal is to understand both, and maybe we have done some of that in this thread.
rScotty

 

[Tx Jim]

JD CC pumps utilized from '65-'92 do not utilize a wobble(swash) plate. I'll reiterate IMHO changing hyd system from CC to OC might be doable but will cost more $$$$$ & time than the cost of hyd pump to replace/alter valves from CC to OC configuration.

I remember attending JD sales & service meetings declaring how great CC hyd's were when compared OC hyd's utilized on other new tractor brands such as Ford & how much more fuel efficient CC hyd's were compared to OC hyd's. Today as you stated most lower priced new equipment has OC hyd's leaving some higher priced equipment to CC & CCLS hyd's. Having spent yrs diagnosing CC hyd malfunctions I'd choose OC hyd over CC hyd's any day for general farming operations.

 

[rScotty]

....snip...... Having spent yrs diagnosing CC hyd malfunctions I'd choose OC hyd over CC hyd's any day for general farming operations.

I agree. In fact, all of my equipment is OC. But I don't want to give anyone following along the wrong idea. OC vs CC isn't the most important thing that makes a tractor a good one or not.
IMHO, some of the best ever 2wd farm machinery ever was the 20 thru 40 series JDs built in the mid 1960s and thru the 1970s. Most of that was CC (not all), but the quality of those tractors was so high that it compensated. A lot of them would compete well on the farm today. You still see them in use around here, especially for haying & 80 acre crop farming. Working well and running fine.