Looking at the lever of my pump, on the right side the lower port says OUT....above and to the right it says GRESEN and something below it I cannot clearly make out....WHISPER, maybe.... directly above the OUT between the two upper ports is has 550 in letters bigger than Gresen. Have found a lot of pictures of 300 and 400 Gesen pumps and the 550 is right where the 300 and 400 are on them. To the right of the 550, on the molding of the port itself, it has 8/12/68 in letters a little smaller than the 550..have not seen anything like that on any of the 300 or 400 models.....will take see if I can get some of the paint off the controller and check for other numbers/casting features and get some pictures of them...thanks for the literature....
Gresen 550
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J_J
Super Star Member
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- Power-Trac 1445, KUBOTA B-9200HST
Just curious if you have done the test I ask for.
Remove the hoses from the cylinders and place in a bucket.
Does fluid flow out of both work ports or only one work port when you pull the lever. Which hose, if any has flow when you push the lever.
Remove the hoses from the cylinders and place in a bucket.
Does fluid flow out of both work ports or only one work port when you pull the lever. Which hose, if any has flow when you push the lever.
Okay.......just got home. Here's what I did and what happened... Pulled the hoses off of both cylinders and lead them both to the right side of tractor so could watch them side by side as my son and I worked the controller's lever. Both of the cylinders put out as close to the identical amount of oil as you could possible estimate when you pulled back on the handle. Was interesting that when I pushed on the controller lever, the port furthest from the lever did nothing, the port closest to the lever actually discharged a little oil under a little pressure...time after time... Put the T onto the port closest to the lever, hooked up the cylinders to the T and plugged the other port. Bucket went up fine when I pulled on the lever, but creeped up slightly/slowly when I pushed on the lever...my son goes about 300 pounds and was able to climb onto it and could barely make it go down. Moved the T to the port furthest from the lever and plugged the one closest to the lever. This was the port that did nothing when pushing on the lever when the hoses were off... With the hoses hooked to the T, the bucket did nothing when I pushed on the lever...son got on the bucket could easily make it go down using his weight, but did not move up on down on its own. In both cases, bucket dropped nice and easy when you shut the tactor off and pushed on the lever... So, not sure what am looking at..but I think the Gresen 550 must be uniquely designed to handle two one way ports with each cylinder plumbed out of a separate port...and mine is worn out or clogged up in such a way after 45 years that it will allow gravity to feed the oil back to the sump with the tractor running... Guess I need to decide how important keeping it stock is to me, would be nice but having it work right would be even nicer.... Got too dark to do much more, but going to pull the controller tomorrow andtake it to a hydraulics shop about an hour's drive from here that a friend has recommended. Will see what they would charge to rebuild it... I know I can replace it for about a hundred bucks...so will see what they want and decide how badly I want it to stay stock.... At least I am comfortable that I know what I got and what is wrong and can make an informed decision.. Really do appreciate all the help and interest, sure know a whole lot more about hydraulice that I ever thought I would at this point in my life...Thanks JJ, really appreciate it man... you get to Newport News, Virginia....I owe you a bunch of beers and a ride on a 1967 Oliver.
Just re-read the previous response.... what I was trying to say was that the loader went up nice and easy with no binding or noise when the T was put into either of the two ports and I pulled on the handle. It did not go down when the lever was pushed...and in fact crept up a bit/slowly when the T was put into the port closest to the lever...this was the one that had a slight presurized discharge when hoses were in the bucket and I pushed the lever.. hope this clarifies the garbled part about what happened. Thanks again.
oldnslo
Super Member
VA,
Read your post twice and would like to confirm that with the hose connected to the port closest to the handle the loader did not lower even with your son in the bucket.
Did it lower smoother when the hoses where connected to the port farthest from the handle? I believe yes but just want to confirm.
It almost sounds like the port closest to the handle is connecting pressure & Tank to the closest port when you push on the handle and there is enough back pressure to just raise the loader. I still suspect some blockage in your tank line causing the problem. $64 question is, where is this blockage located... Could be limited spool movement on valve, partial blockage of a tank fitting or hose, etc..
Dumb question but, have you measured the spool travel from center in both directions on your 550 valve. Most valves this distance is usually very similar. If there is a significant difference I would suspect something is preventing the valve from shifting fully in one direction.
Read your post twice and would like to confirm that with the hose connected to the port closest to the handle the loader did not lower even with your son in the bucket.
Did it lower smoother when the hoses where connected to the port farthest from the handle? I believe yes but just want to confirm.
It almost sounds like the port closest to the handle is connecting pressure & Tank to the closest port when you push on the handle and there is enough back pressure to just raise the loader. I still suspect some blockage in your tank line causing the problem. $64 question is, where is this blockage located... Could be limited spool movement on valve, partial blockage of a tank fitting or hose, etc..
Dumb question but, have you measured the spool travel from center in both directions on your 550 valve. Most valves this distance is usually very similar. If there is a significant difference I would suspect something is preventing the valve from shifting fully in one direction.
J_J
Super Star Member
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- Sep 6, 2003
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- 18,952
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- JACKSONVILLE, FL
- Tractor
- Power-Trac 1445, KUBOTA B-9200HST
I agree with oldnslo.
That is one odd working valve.
Could you run a hose from the OUT port of the FEL valve directly to tank to eliminate any potential blockage.
What is puzzling though is that when the tractor is off, he says the loader drops fairly fast. How fast depends on the load of the bucket and or contents.
Could it be that someone removed the spool and modified the porting to accomplish a specific task.
Has anyone ever heard of a valve that connect work port A to one lifting cyl and work port to the other lifting cyl on a loader.
I can't think of a valve made today that would do that.
Did anyone mentioned hyd pressure while doing all this testing, checking out the relief pressure, back pressure, any pressure with valve in neutral. etc.
That is one odd working valve.
Could you run a hose from the OUT port of the FEL valve directly to tank to eliminate any potential blockage.
What is puzzling though is that when the tractor is off, he says the loader drops fairly fast. How fast depends on the load of the bucket and or contents.
Could it be that someone removed the spool and modified the porting to accomplish a specific task.
Has anyone ever heard of a valve that connect work port A to one lifting cyl and work port to the other lifting cyl on a loader.
I can't think of a valve made today that would do that.
Did anyone mentioned hyd pressure while doing all this testing, checking out the relief pressure, back pressure, any pressure with valve in neutral. etc.
With the T connected to the port closest to the handle, the loader crept up when I pushed on the handle. My son could stop the slow creep up, but if it was going down at all it was not really perceivable. With the T connected to the port furthest from the lever, the loader did not go down without my son putting his weight on it, it just sat there as I pushed the lever....e.g., did not creep up like it did with the T in the port closest to the handle. With one hose connected to each port and with the T in either port, you could basically make the loader drop like a rock with the engine off. If you pulled the lever back quickly after pushing it in all the way, you could actually rock the tractor..almost dumped my son...so am not sure how that fits into your theroy of blockage. Did not really pay any attention ot the spool travel...you could not make it go down with engine running and with it off, you could not push it in all the way as it dropped to fast...just do not recall any big difference in travel, but am thinking that you are probably right about something preventing the valve from shifting fully in one direction.... only thing that really seems to make sense... would really be curious to see if anyone else has ever heard of or has any experience with a Gresen 550...have only had this tractor for the last four of it 46 years, so is hard to tell what mods have been made to it over the years...no obvious signs that the controller has ever been opened up though and I looked very closely.
Leejohn
Elite Member
He isn't getting full travel when he is pushing the handle in. The handle is wore and the bracket it is mounted in. If you look at the 1st picture the handle is bottoming out on the screw holding the bracket. Over the years it's cocking the spool and letting pressure by on the down side. If he hasn't pulled the valve he might try opening and closing with out the handle and at the same time check for up, down, and side movement in the spool. He could maybe turn the spool 180 deg.
In his pictures also look at the paint missing above and below on the spool handle. If that doesn't help it's new valve time. Oh one other thing, there could be a brass bushing on the spool in the valve body under the cover, if bad that would give slop in the spool.
In his pictures also look at the paint missing above and below on the spool handle. If that doesn't help it's new valve time. Oh one other thing, there could be a brass bushing on the spool in the valve body under the cover, if bad that would give slop in the spool.
The bucket drops quicker than "fairly" fast with the engine off...you push the lever all the way and it drops darn quick...and when you add weight to the bucket it drops even faster.
Did not have any gauges to test any pressures. With the lever in the neutral position, and both hoses in the bucket, there was no oil coming out of either hose....with both hoses connected to a different port, when you pulled the lever...they seemed to be putting out as close to an identical amount of oil as you could see with out doing a detailed measurement. When you pushed the lever with each hose hooked up to a separate port, the hose hooked up to the port furthest away discharged no oil, while the hose closest had a small amount....a trickle I guess you would have to call it....flow out under what seemed like slight pressure, e.g, more than just gravity flow.... Am thinking will just go ahead and put a new valve on it and paint it Oliver green if this guy wants much over the price of a new valve to rebuild this one. If that is how it works out, will tear it down and send you pictures of it....if this guy rebuilds it, will ask him to describe what the heck he found when he opened it up...... and will pass along the results of either scenario to you all....
Did not have any gauges to test any pressures. With the lever in the neutral position, and both hoses in the bucket, there was no oil coming out of either hose....with both hoses connected to a different port, when you pulled the lever...they seemed to be putting out as close to an identical amount of oil as you could see with out doing a detailed measurement. When you pushed the lever with each hose hooked up to a separate port, the hose hooked up to the port furthest away discharged no oil, while the hose closest had a small amount....a trickle I guess you would have to call it....flow out under what seemed like slight pressure, e.g, more than just gravity flow.... Am thinking will just go ahead and put a new valve on it and paint it Oliver green if this guy wants much over the price of a new valve to rebuild this one. If that is how it works out, will tear it down and send you pictures of it....if this guy rebuilds it, will ask him to describe what the heck he found when he opened it up...... and will pass along the results of either scenario to you all....
Leejohn
Elite Member
When you push the lever and oil is coming out it doesn't matter how much the free flow is blocked somewhat. I would also guess the other port doesn't have 100% free flow.
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