rScotty
Super Member
- Joined
- Apr 21, 2001
- Messages
- 8,391
- Location
- Rural mountains - Colorado
- Tractor
- Kubota M59, JD530, JD310SG. Restoring Yanmar YM165D
I got a chance to play with this. I just swapped the swing hoses from their control valve onto the boom control valve and vice versa. The problem moved to the boom! I had no power for boom down!
So now the problem is isolated to the control valve or the actual pump? Steering seems fine, and I have power in 1 direction, so I'm assuming the pump and main relief is ok. So I think that means the actual control valve is the issue???
ac
Wow! It's always good to run more tests. And that one provided real results..... I'm very impressed.... and glad you didn't just go and pull the swing cylinder apart.
OK,,, some questions.
1. You first posted on this problem with an L45 back almost 7 years ago in 2013 after a friend had used your hoe. Is this the same L45?
2. Which way is "Left"? Facing forward left or in backhoe operator position?
3. Why would it not be control or relief valve? I believe there is a separate swing pump - but don't see how that could cause a problem in one direction only. Does the L45 have a separate steering pump, too?
4. Hmmm.....could it be a relief valve? We know people have had problems with relief valves in that circuit before. Is there any way? I need to look at the hydraulic schematic to determine that - more about hydraulic schematic reading below..
How about one more test.... just to confirm things? Is it necessary or reasonable?
If you swap hoses again, I'm thinking that the stabilizers are also 2 way cylinders with an easily defined right and left.
Re the hydraulic schematic. I've been doing a self-study on hydraulic schematics. Fluid Power World published an excellent series of tutorials beginning with simple circuits and progressing up through fairly complex systems. All free and online. Keyword is "Hydraulic Symbology" by Mary Gannon and Josh Cosford. On the Fluid Power World publication website.
I'll take a look at the Kubota Shop Manual tonight and see if I can get any insight into what you've learned by swapping hoses.
Luck,
rScotty