Gresen 550

[VAFarmer6]

I have a 1967 Oliver 550. It has a front end loader that uses one way cylinders on each side of the tractor to lift the bucket and a pull cable to dump the bucket, about as simple a setup as you can get. One hose from the bottom of each cylinder leads to a controller marked "Greson 550". The only other markings there are "8/12/68" which I assume is the year it was manufactured. Looking at the controller handle, the lower left side has a port labeled IN and the lower right side is marked OUT. Hoses in and out of these ports lead to the tractor's hydraulic sump. Each of the two hoses from the cylinders lead to a separate port on the top of the contoller. This setup/system lifts huge loads very quickly without any jerking or binding of any sort when you pull the lever...and when you push the lever, the bucket goes down, but slower than it seems like it should...and much much slower that it does if you turn the tractor off and then push the lever in. A friend says it is plumbed wrong and both hoses should be plumbed through a T fitting to only one of the ports on top and NOT one hose to each of the top ports as it is now. He is convinced it is magic that it works at all plumbed like it is. I can find no information on a Greson 550...am wondering if maybe it is a Greson made specfically for the Oliver 550????? Anyone familar with this controller and how it should be plumbed to handle two one way cylinders? Thanks for any help.

 

[J_J]

Perhaps some pictures might help ID the valve.

Do you want a new valve?

You can do the same thing with a single spool, single action valve, or a DA single spool valve , with the A work port plugged.

 

[VAFarmer6]

Perhaps some pictures might help ID the valve.

Do you want a new valve?

You can do the same thing with a single spool, single action valve, or a DA single spool valve , with the A work port plugged.

Loader lifts fine...and would like to keep it as stock as I can and still use it.....really does go down slower than I think it should though...NOt sure if problem is it is plumbed wrong or that a 45 year old valve needs new rubber/springs/cleaning out????? Would it hurt anything if I hooked both hoses to a T and tried it out using one top port and plugging the other and the reversing the two to see if one worked better than the other????
Hope I figured out how to upload the pictures, please bear with me, here....

 

[J_J]

It appears that that is a DA hyd vale and they are using it in a SA cyl configuration.

I don't know your hyd pressure, but you should be using hyd fitting instead of the water pipe fittings.

The one pressure work port should be be going to a tee which will go to each cyl.

If the QD is in the return flow, it might be slowing things down.

When your cyl are lifting, you provide flow to the SA cyl, and when you lower, the flow flows back through the same line to the other work port and to tank.

The flow from the cyl should be at very little pressure, and pass through the return line uninterrupted.

When the valve is in neutral, the flow goes in the IN port and through the OUT port to tank.

Where is the pull valve you mentioned?

 

[VAFarmer6]

Service Manual says system operates at 1500 psi.....add 45 years to that and it is probably still high enough I should get rid of the water pipe...some of those fitting may well be 45 years old as well.

Pull valve??? I was talking about pulling and pushing the lever on the controller...don't remember/see anything about a pull valve. Not sure I understand the DA, SA, QD terms, but understand you agree with my friend that is should have a tee on one port as opposed to having each cylinder hose being attached to its own port. Would it make any difference if I used the port closest or the furthest from the handle...would experimenting to see if one worked better than the other potentially hurt anything?

 

[J_J]

Both cyl should be connected to the same port.

You said pull cable. What is the pull cable pulling on.

The way most double action valves are used with a single action cyl, is when you push the lever, you cause fluid to flow to the cyl base end, raising the loader.

When you pull the lever, the other work port will allow the fluid to flow to tank.

What some people do is plug the A work port and only use the B work port to raise and lower the loader.

When you use the valve like this, you cause fluid to flow out the B work port to raise, and when you pull the lever back, the B work port dumps the fluid to tank.

Fluid should be going to both cyl at the same time. One hose from one work port going to a tee and then to each cyl.

QD = quick disconnect

 

[Leejohn]

Are you 100% sure the pressure line is pressure from the tractor? The reason I ask is most of the time the return is low on the sump. Make sure there isn't pressure on both lines, if there is only one hose getting pressure the loader would be tristing real bad with any load at all. The cyls plumbing has to be changed.

 

[J_J]

Go ahead and connect the two cyl to a TEE and run the one line back to the B work port.

Run the other work port to tank.

If you want to find out which line is the pressure line, remove both lines from the valve and place in a bucket. Start tractor and you will see which one has flow.

Where is the QD line going?

 

[J_J]

Go ahead and connect the two cyl to a TEE and run the one line back to the B work port.

Run the other work port to tank.

 

[oldnslo]

If the loader is lifting correctly you have pressure going to both cylinders so it would make me question why it would require plumbing changes. With a normal DA valve spool only one cylinder would be getting pressurized and the loader would only lift with one cylinder causing it to twist like leejohn stated.

Gresen did make some some oddball and or special valves. It is possible this is one of them. To check the valve function will require removing the hoses from the valve and them determining flow path with valve handle pulled and pushed.

 

[VAFarmer6]

.....pull cable... The bucket itself does not have any hydraulics on it. To actually dump the bucket, you have to pull a cable that connects to a mechanical catch with a lever that opens the catch. If you are lucky you can pull on another cable that is attached to the bucket itself and snap it back into the catch while it swings/rocks back and forth empty....if not, you have to lower the bucket/loader to the ground to snap it back in place ...or get off the tractor and do it by hand... so, this is the primary incentive to get the darn thing to lower quicker than it does.... about as basic of a loader as you can get...absolutely no markings on it any were except for the controller being a Gresen 550 and possible made 8/12/68....do not think it is factory, but has lasted some 45 years and appears to have taken some serious abuse.

 

[VAFarmer6]

Hopefully the previous reply answers the question as to why I would like it to go down faster..... The I put the QD on about a year or so ago, when I blew a hose fitting at the bottom of the left cylinder....had to cut old hose off as it had no swivel in the hose line, which I found interesting...not sure how they got the hose on originally. Have since taken the QD out and put in a swivel as my friend why thinks it need to be replumbed with a T fitting thought that might be slowing it down...seems a bit faster maybe, but still seems to take forever to lower to the ground without turning tractor off. Appreciate the history on Gresen...found it curious that I had a Gresen 550 valve on my Oliver 550... They made a bunch of Oliver 550's, so maybe Gresen made this valve for whoever made these loaders???? As I said, the loader lifts what I consider huge loads quickly and perfectly balanced...absolutely no twisting or binding anywhere...so I am hesitant to change plumbing around...would seem introducing a T fitting would add some restrictions to the current flow pattern.

 

[oldnslo]

Hopefully the previous reply answers the question as to why I would like it to go down faster..... The I put the QD on about a year or so ago, when I blew a hose fitting at the bottom of the left cylinder....had to cut old hose off as it had no swivel in the hose line, which I found interesting...not sure how they got the hose on originally. Have since taken the QD out and put in a swivel as my friend why thinks it need to be replumbed with a T fitting thought that might be slowing it down...seems a bit faster maybe, but still seems to take forever to lower to the ground without turning tractor off. Appreciate the history on Gresen...found it curious that I had a Gresen 550 valve on my Oliver 550... They made a bunch of Oliver 550's, so maybe Gresen made this valve for whoever made these loaders???? As I said, the loader lifts what I consider huge loads quickly and perfectly balanced...absolutely no twisting or binding anywhere...so I am hesitant to change plumbing around...would seem introducing a T fitting would add some restrictions to the current flow pattern.

VA,
without physically looking at your loader and valve I am 99% sure it is plumbed correctly or it wouldn't work at all. What there may be is some form of restriction in tank line on your valve limiting down speed. With your tractor running your valve is directing the pump flow and return flow from the loader cylinders to tank. With the engine off there is no pump flow and the loader could drop quicker. Since this loader is gravity down a slight restriction could affect your speed. I.e. spool travel limited from junk build up in centering spring retainer, piece of trash stuck in fitting, old return hose delaminating and the inner tube is blocking the oil flow, etc.

Do you have any way of installing a gauge in one of the loader lift circuits. Be curious to see what the lowering pressure is.

Does the rate of drop change with a loaded bucket Vs empty?

I put a lot of hours on a similar style loader on a "B" John Deere and hated the cable dump when loading soupy manure. It seemed like there was always a splash back when dumping the darn things..

 

[J_J]

VAFarmer6 has not answered the question, what is connected to the QD hose.

He said there is no tee, so how are both cyl lifting?

If someone is using a DA valve with a set of SA cyl, both cyl are connected to a tee and connect to the B work port, and the A work port is either sent to tank or plugged.

The A work port is usually close to the handle.

Is the A work flow going to tank.

How about some pictures of the hoses connected to the lift arms.

Are the two lifting cyl connected together?

 

[VAFarmer6]

There is absolutely no doubt that the more weight in the bucket; the faster the loader drops......
The Oliver 550's concept of power steering is all the power you have...so by the time you get done driving it around with a full bucket and then pull the cables to dump and reset the bucket, you get a full upper body workout....fortunately no longer dealing with feeder lots and all that "splash back" that I did when growing up on the farm... should probably just part it out, but grew up on one of these things and working with and on it brings back a lot of good memories. Found/bought it in 1999 and except for this loader thing and the power steering, the rest of it (engine,transmission, PTO, 3 Point Hitch, etc.,) make it a great/powerful little tractor.
I am thinking that the rubber fittings may have degenerated and perhaps the springs have rusted enough over the years and there is too much junk in the end of the port to allow the valve to open up far enough to shut off all pressure and allow the oil to drain back to the sump... would make sense why it works so well going up and drops so nicely with the tractor off... just hate to tear into something like this not having any idea what I am going to find without a diagram...or anyway to order a rebuild kit for a Geson 550 that no one seems to have ever heard of......

 

[J_J]

Can you answer some of our questions so we can help you figure this out?

With the engine running, and the valve in neutral, the flow is passing through the valve to the return hose and to tank.

When you lower the lift arms, with engine running, the flow from the cyl is mixing with the pump flow and flows to tank.

If the loader is raised, and engine off, and you then lower the lift arms, you only have the fluid flowing from the cyl flowing to the tank. Less restriction.

 

[VAFarmer6]

Thread is getting too long to keep track.... I have since taken of the QD and replaced it with a swivel...didn't speed things up preceivably. The QD was on the hose that led to the bottom of the left loader cylinder...the other hose coming out of the top leads to the bottom of the right loader cylinder. It lifts fine and what I think is quickly with no binding/twisting, etc.... One of the bottom hoses goes into a port labeled IN and the other bottom hose is connected to a port labeled OUT. Both of those hoses go to what appears to be the tractor's hydraulic sump. The two lifting cylinders have one hose connected to the bottom of each cylinder. The other end of the left cylinder's hose is attached to the top port closest to the controller's handle and the other end of the right cylinder is connected to the top port furthest from the controller's handle, The cylinders are not cross connected in any way other than the hose from them lead to the same controller.
In looking at all the feed back, is it possible that this Gresen 550 was specfically designed for a loader on an Oliver 550 and is some sort of hybred cross between a DA/SA controller. Would love to order a rebuild kit..hopefully that had some sort of schematic/diagram and rebuild it. Reading the comments, am starting to suspect it has 45 years of junk in there that is keeping the piston from sliding far enough to shut off all the pump's pressure and slowing the gravity feed down to a trickle...would that be a possibility???

 

[J_J]

What would happen to a cyl that was connected to tank and the one SA cyl was forced to extend the lift arms by the other cyl.

It might not twist at all as there is flow to fill the other cyl by drawing from the tank.

That is a DA valve and I have never heard of connecting a SA cyl to A work port and the other cyl to the B work port.

That is not how it is done.

Why not remove both hoses from the cyl and place in a bucket and verify that when the lever is pushed one way, there is flow from one port, and when the lever is pushed the other way, there is flow from the other port.

That will verify whether it is a DA valve.

If there is flow from both work ports at the same time, I will have to relearn some things.

 

[oldnslo]

VA,
Which way do you move the lever to raise? Pull it towards you or push it towards the fender?

 

[oldnslo]

What would happen to a cyl that was connected to tank and the SA cyl was forced to extend by the other cyl.

It might not twist at all as there is flow to fill the other cyl by drawing from the tank.

That is a DA valve and I have never heard of connecting a SA cyl to A work port and the other cyl to the B work port.

That is not how it is done.

JJ,
Think about this for a minute. If this is a double acting valve then when I pull the lever port "A" would be to pressure and port "B" would connect to tank and the loader would try and lift with one cylinder. Push on the lever and now port "B" would connect to pressure and port "A" would connect to tank and now the other cylinder would be trying to raise the loader.

I suspect this is an old custom built valve for single acting loaders or it would not work at all. Since Gresen was purchased by Parker many years ago getting any technical support will be difficult.