L39 power steering problem

[Kp12]

I put new seals and o rings in the hydraulic valve that controls the steering on an l39 after I installed it the steering wheel shakes and turns all the way. To the left or right on its own. I don't know if it's air in the system or if I could have installed something wrong. Any help would be apreciated thanks

 

[whitetiger]

It is not from air..What L39? Are you refering to a steering motor / hand pump?

 

[Kp12]

its for a kubota l39. its a steering valve, and it uses the pressure from the hydraulic system for the power steering. so when i turn the steering wheel it opens and closes the the valve giving pressure to the rams on the front axle

 

[whitetiger]

If you are refering to the "valve" the steering wheel mounts on, you either have hoses in the wrong place or did not reassemble the "valve" correctly. Some hydra motors have to be timed to work properly, do not remember on an L 39. Also if it is not perfectly clean when reassembled the spool will bind up and will act as you discribe.
The commutator plate too tight or upside down on contaminated will also cause this symptoms.

 

[JJohonness]

KP12 did you ever get the pump working correctly? I have a leaky power steering pump on my l39 and I am trying to decide if I should replace the seals and bearings or just buy the whole pump.

 

[lesselby]

I, too, had this problem. After buying my L39 new and putting abut 500 hours on it, the top spool retainer o ring started leaking. New o rings would only solve the problem for a few hours or days, depending on temperature, to a certain extent. It would leak mostly when the oil warmed up, especially on a hot day. After replacing the o ring about 6 times, I decided to take the whole valve apart to see if I was missing another seal inside that might be defective, even though the parts schematic didn't show any. (my repair manual doesn't show any details of the steering valve, I had to get it from the dealer) After taking it apart, replacing all o rings and seals, I put it back together, thinking that orientation wasn't critical. I put the valve back in the tractor and had the same exact problem as KP12 above. I called four different dealers and only one of the service managers had heard of the problem before. He simply said that the customer had taken it apart and must have broken something and sold him a new valve to the tune of about $1000.00. I knew nothing was broken so I got on line, like KP12 did. No one gave him a correct answer, so no one else would know how to fix the problem.

The valve is or seems to be a copy of an Eaton, Char-Lynn valve. It has Syn Gin on the casting so I don't think it was made by Eaton, however, the design is a basic one and they are made, pretty much, the same way, according to the Eaton-Char-Lynn rep that I talked to. He told me how to time the valve and emailed me the instruction sheet.

Yes, it is a timing issue!

With the valve in front of you with the ports facing you and the open end that the geroter goes in, up, you make sure that the dowel pin in the spool valve is horizontal to the port face. The geroter is then installed with the gear roots horizontal to the port face and all the way to the side that is at the 12 o'clock position.

I also took 600 grit emery cloth and polished the o ring cavity in the cast iron housing on the spool end, which looked a little grainy being cast iron. I then polished it a bit more with Simichrome polish. I cleaned it up, put a new o ring in and used a brand new spring clip to hold the spool valve retainer in place.

The valve works perfectly and also doesn't leak, so far, after about 50 hours of hard use.

I hope this helps someone else because I know the frustration of trying to get this thing to work, knowing that nothing is broken, and of course not wanting to shell out $1000.00 needlessly. One dealer did refer me to a hydraulic shop to have it repaired, but I got his email after I had fixed it. The dealers have no information on how to repair this valve and would probably just tell the customer that it can't be fixed and to just buy a new one, plus installation costs. Typical!

 

[whitetiger]

I, too, had this problem. After buying my L39 new and putting abut 500 hours on it, the top spool retainer o ring started leaking. New o rings would only solve the problem for a few hours or days, depending on temperature, to a certain extent. It would leak mostly when the oil warmed up, especially on a hot day. After replacing the o ring about 6 times, I decided to take the whole valve apart to see if I was missing another seal inside that might be defective, even though the parts schematic didn't show any. (my repair manual doesn't show any details of the steering valve, I had to get it from the dealer) After taking it apart, replacing all o rings and seals, I put it back together, thinking that orientation wasn't critical. I put the valve back in the tractor and had the same exact problem as KP12 above. I called four different dealers and only one of the service managers had heard of the problem before. He simply said that the customer had taken it apart and must have broken something and sold him a new valve to the tune of about $1000.00. I knew nothing was broken so I got on line, like KP12 did. No one gave him a correct answer, so no one else would know how to fix the problem.

The valve is or seems to be a copy of an Eaton, Char-Lynn valve. It has Syn Gin on the casting so I don't think it was made by Eaton, however, the design is a basic one and they are made, pretty much, the same way, according to the Eaton-Char-Lynn rep that I talked to. He told me how to time the valve and emailed me the instruction sheet.

Yes, it is a timing issue!

With the valve in front of you with the ports facing you and the open end that the geroter goes in, up, you make sure that the dowel pin in the spool valve is horizontal to the port face. The geroter is then installed with the gear roots horizontal to the port face and all the way to the side that is at the 12 o'clock position.

I also took 600 grit emery cloth and polished the o ring cavity in the cast iron housing on the spool end, which looked a little grainy being cast iron. I then polished it a bit more with Simichrome polish. I cleaned it up, put a new o ring in and used a brand new spring clip to hold the spool valve retainer in place.

The valve works perfectly and also doesn't leak, so far, after about 50 hours of hard use.

I hope this helps someone else because I know the frustration of trying to get this thing to work, knowing that nothing is broken, and of course not wanting to shell out $1000.00 needlessly. One dealer did refer me to a hydraulic shop to have it repaired, but I got his email after I had fixed it. The dealers have no information on how to repair this valve and would probably just tell the customer that it can't be fixed and to just buy a new one, plus installation costs. Typical!

I gave him the correct answer on Jan of 2012 in this very thread.

 

[lesselby]

Sorry whitetiger, you are right, you did say it was a possible timing problem, but, you didn't say how to time it. I wasn't clear what I meant, in that, it was like having a combination lock and not having the combination to unlock it. I tried to give the "correct answer" by giving the "combination" to "unlock" it. Also, that it is definitely a timing problem. The feed/return hoses are almost impossible to install wrong, but the left/right hoses can be put on opposite, which it did. The only result is that turning the steering wheel left made the wheels turn right, and vice versa, with no shudder or self turning problem. The commutator plate appears to be symmetrical on this unit, so getting it disoriented shouldn't be a problem, although I did mark mine before disassembling it and put it back together accordingly.

Hope that clears the air! I'm not trying to step on anyone's toes or puff my ego, I just wanted to save someone else from going through the nightmare I went through to find out how to fix the valve. Best wishes!

 

[heyu]

Re steering problem

Hi Whitetiger
I too have a power steering problem. Hard steering on right side. b2100. I posted yesterday no results. Any ideas'
ken

 

[nicholaslunn]

I, too, had this problem. After buying my L39 new and putting abut 500 hours on it, the top spool retainer o ring started leaking. New o rings would only solve the problem for a few hours or days, depending on temperature, to a certain extent. It would leak mostly when the oil warmed up, especially on a hot day. After replacing the o ring about 6 times, I decided to take the whole valve apart to see if I was missing another seal inside that might be defective, even though the parts schematic didn't show any. (my repair manual doesn't show any details of the steering valve, I had to get it from the dealer) After taking it apart, replacing all o rings and seals, I put it back together, thinking that orientation wasn't critical. I put the valve back in the tractor and had the same exact problem as KP12 above. I called four different dealers and only one of the service managers had heard of the problem before. He simply said that the customer had taken it apart and must have broken something and sold him a new valve to the tune of about $1000.00. I knew nothing was broken so I got on line, like KP12 did. No one gave him a correct answer, so no one else would know how to fix the problem.

The valve is or seems to be a copy of an Eaton, Char-Lynn valve. It has Syn Gin on the casting so I don't think it was made by Eaton, however, the design is a basic one and they are made, pretty much, the same way, according to the Eaton-Char-Lynn rep that I talked to. He told me how to time the valve and emailed me the instruction sheet.

Yes, it is a timing issue!

With the valve in front of you with the ports facing you and the open end that the geroter goes in, up, you make sure that the dowel pin in the spool valve is horizontal to the port face. The geroter is then installed with the gear roots horizontal to the port face and all the way to the side that is at the 12 o'clock position.

I also took 600 grit emery cloth and polished the o ring cavity in the cast iron housing on the spool end, which looked a little grainy being cast iron. I then polished it a bit more with Simichrome polish. I cleaned it up, put a new o ring in and used a brand new spring clip to hold the spool valve retainer in place.

The valve works perfectly and also doesn't leak, so far, after about 50 hours of hard use.

I hope this helps someone else because I know the frustration of trying to get this thing to work, knowing that nothing is broken, and of course not wanting to shell out $1000.00 needlessly. One dealer did refer me to a hydraulic shop to have it repaired, but I got his email after I had fixed it. The dealers have no information on how to repair this valve and would probably just tell the customer that it can't be fixed and to just buy a new one, plus installation costs. Typic

I, too, had this problem. After buying my L39 new and putting abut 500 hours on it, the top spool retainer o ring started leaking. New o rings would only solve the problem for a few hours or days, depending on temperature, to a certain extent. It would leak mostly when the oil warmed up, especially on a hot day. After replacing the o ring about 6 times, I decided to take the whole valve apart to see if I was missing another seal inside that might be defective, even though the parts schematic didn't show any. (my repair manual doesn't show any details of the steering valve, I had to get it from the dealer) After taking it apart, replacing all o rings and seals, I put it back together, thinking that orientation wasn't critical. I put the valve back in the tractor and had the same exact problem as KP12 above. I called four different dealers and only one of the service managers had heard of the problem before. He simply said that the customer had taken it apart and must have broken something and sold him a new valve to the tune of about $1000.00. I knew nothing was broken so I got on line, like KP12 did. No one gave him a correct answer, so no one else would know how to fix the problem.

The valve is or seems to be a copy of an Eaton, Char-Lynn valve. It has Syn Gin on the casting so I don't think it was made by Eaton, however, the design is a basic one and they are made, pretty much, the same way, according to the Eaton-Char-Lynn rep that I talked to. He told me how to time the valve and emailed me the instruction sheet.

Yes, it is a timing issue!

With the valve in front of you with the ports facing you and the open end that the geroter goes in, up, you make sure that the dowel pin in the spool valve is horizontal to the port face. The geroter is then installed with the gear roots horizontal to the port face and all the way to the side that is at the 12 o'clock position.

I also took 600 grit emery cloth and polished the o ring cavity in the cast iron housing on the spool end, which looked a little grainy being cast iron. I then polished it a bit more with Simichrome polish. I cleaned it up, put a new o ring in and used a brand new spring clip to hold the spool valve retainer in place.

The valve works perfectly and also doesn't leak, so far, after about 50 hours of hard use.

I hope this helps someone else because I know the frustration of trying to get this thing to work, knowing that nothing is broken, and of course not wanting to shell out $1000.00 needlessly. One dealer did refer me to a hydraulic shop to have it repaired, but I got his email after I had fixed it. The dealers have no information on how to repair this valve and would probably just tell the customer that it can't be fixed and to just buy a new one, plus installation costs. Typical!

I have the same problem with my Kubota L39 tractor. Any Picture or a pdf for the timing procedure.