Hydraulic puzzler?

[Milo Holroyd]

Howdy folks. Today I installed my snowplow on the L2550GST 4WD.
It's an old truck plow, with single acting angle cylinders.

I have used it for 20+ years on my 1979 L245DT. I use the bucket tilt cyl. lines (open center control valve) for the plow angling. I can't get it to angle on the newer tractor. (joy stick type control). What am I missing? Do I need to replace the two single acting cyl's. with one double acting?

As it is right now, it will angle one way only. Dead heads the other way. Reversing the lines, only changes the direction it moves. Still deadheads in the opposite direction.

Appreciate any help.

Peace
Milo

 

[yooper jim]

Push stick hard to the right. You will feel a detent click. Then it will work both ways. Had the same problem.
Jim

 

[Milo Holroyd]

Thanks for the reply yooper jim. Just went out to the barn and tried your suggestion. Hmmmm, seems I don't have a valve like yours

I've included some pics.

 

[yooper jim]

You have a different valve, but that was my problem. I have one DA cyl to angle the blade and it only went in one direction. If I reversed the two lines, it worked the opposite direction. Seems to me, that if you have two SA cyls, it should work. Pressure to one cyl should empty the opposite cyl. Just like it empties the other half of a DA cyl. Open center valve and all that. I could not find it at first and thought they were all nuts telling me about the right detent. I can't even tell you why you have to do it. It is not an all the time thing. Just once in a while. Hope you solve your problem. I copy catted this fellows frt blade conversion.
Jim

 

[Milo Holroyd]

Thanks for your help yooper jim. I may hook a DA cyl up to the lines in the morning, see what happens.

Peace
Milo

 

[Milo Holroyd]

I hooked the hoses to a DA cyl this morning. Works fine.
Looks like I'm gonna have to find a small DA cyl to use on the plow.

Peace
Milo

 

[yooper jim]

Great! If looking for a new cyl try: surplus center

 

[Milo Holroyd]

Follow up: Hydraulic puzzler..........
As previously posted, I temporarily hooked up a DA cyl. this morning.
Based on the successful function of that cyl. I purchased a small DA cyl. from TSC. Installed it on the plow. Plumbed it up............and to my dismay it acted the same as the single action cyl. WTF!!!

insert revelation here>>

When I first started this swap, I installed quick connects on both lines feeding the tilt cyl's. I installed one male and one female (quick connect) on each hose.
Did the same for the steel lines going to the front of the loader. That way the lines are always hooked up the same.

That's when I discovered that the lines/hoses are very specific in orientation.
(more than just having the lever/bucket actions reversed). Due to the difference in piston area (full dia. on one side, reduced dia. on rod side) the hoses have to be plumbed correctly.
This morning it was just dumb luck, that I hooked up the DA cyl. correctly!
This afternoon, after the installation of the new DA cyl., and subsequent failure to operate, I remembered the swapping of the tilt cyl's.

Swapped the lines on the new DA, everything works fine.

What makes this spool valve so different from my open center valve on my old tractor? I noted that on the *joy stick* valve, with the tilt cyl. feed lines open to atmosphere, moving the lever one way directed oil out one line. Moving the lever the opposite way directed oil out both lines, one at higher flow than the other. Why? I don't have a clue. But, my plow works now

Sorry this so rambling. But I wanted to post my findings in hope of helping others. If ya think it needs editing, let me know, please.

Peace
Milo

 

[RCtoywizard]

Hello
Very interesting because tomorrow (weather allowing) I am going to finally install my two 15' new lines to run from the rear control to the front end so I can hook up my old truck plow unit.
Good thing you guys posted this because I could envision my frustration, tears,rants and half an empty bottle trying to figure out why it didnt work.
At least if mine does not work, I have options.

Keep ya posted.
Thank you again.

 

[Kubota Newbie]

RCtoywizard,
Have no fear! You should not encounter this problem working off the control for the rear remotes on the tractor. Totally different animal.
RC

 

[Sqidget]

Are you sure you do not have 2 seperate detent on the Right (bucket dump) direction of the control valve? It sounds like you are having a issue with regen. This function is engaged when pushing the control handle to the right. It allows controlled dumping or lowering loads by putting pressure to both sides of the piston. The only difference at this point is piston surface area, the side with the rod has less surface area and allows a slow travel of the rod. On 2 single acting cyls this will deadhead, due to equal surface areas, also with the DA if the lines are reversed it may not move.
For faster loader cycle times a second detent is achieved by pushing the control handle farther to the right, usually past a click or bump(detent) at this point the oil in the released side of the piston is returned to the sump allowing rapid dumping. This is what is needed to use 2 SA cyls.
I have heard of some detents being frozen due to never being used.
you may also consider calling a dealer and asking if the model control valve you have has a regen function.
Hope this helped, Dave