Hey community, my first post. I’m having issues with my backhoe attachment hydraulics. The first issue was that it was leaking from the supply hoses, but l soon discovered that the boom circuit has little or no power. I’ve been into some of the valves but no changes. This machine, l discovered after l bought it was discussed on this forum back in 2016. Wish l had joined before then. I bought it without any knowledge of the problems these machines can have. Not the best decision l ever made. But, l own it now l need to get on with fixing it. Any help will be greatly appreciated. I have many pics and videos of the machine. Just don’t know where to start.
You need to start by explaining the issues your having with as much detail as possible. Lots of expert Deere advise here.
Is the tipper/dump cylinders work OK?
Thanks Vtech63, so the first time l attempted to lift the boom, when l got it off the low boy, it was real sluggish it had barely enough power to get it up and out of the lock position. I found out the hydraulic oil was contaminated It looked pink and milky. So l drained as much out of the tank and the hoses and the two hydraulic rams on the boom, (they were taken off and rebuilt) replaced the filter in the tank cleaned the tank and vent and filled with hyd. Oil from Case. That didn’t help. So l found the valve on top of the body of BH controls in that circuit to have o-rings missing and chunks of what looked like rubber inside the cavity or bore and cleaned all that up. So l bought one on line, and Replaced it. No way to bench test it for correct pressure setting but l did count the threads. And no changes.
Hey TVA, so the dipper seems a bit more responsive though l don’t think any of the circuits have enough pressure. I do have a manual and the thing is l have no experience so I’m starting off fresh as an apprentice, lol. But l do have a mechanical background so as l go I’ll pick up on what you guys are laying down. Yesterday l disconnected the Hoe, and drove the machine up on blocks to get a good look under the machine. There are an array of leaks nothing serious but the wettest area is at the left brake assembly. I will clean it today and try to get a better idea of where it’s leaking. But back to the thread, I’m going to attempt a pressure check today. No flow meter so just pressure. I read the manual and understand the procedure. That’s why l bought that valve. It was a gamble. $90.00 vs. $1700 for a flow meter.
I don’t think you gonna need a flow meter for this one, gauges and maybe some $50 needle valve should suffice!
That looks like a adjustable port relief. To set the pressures on those you have to run the main relief pressure above what your port relief settings are supposed to be......then you bottom out and top out your cylinders to set your port/circuit reliefs.....then you reset your main relief to specs. How is the down pressure on your boom circuit? If you tilted the bucket 45 degrees and pushed the boom lever down....will it pick up the front of the machine and hold it there on its own?
Where is the needle valve? I’ve got a gauge and a tee for getting btwn a hose and a hard line.
You going to need needle valve only to pressure test the pump if it will come to that. For now just do what Vetech advises - he is very experienced old timer, so he knows almost everything, ( sometimes he may be little grumpy, though )!
If you have the proper service manual, check for a section on “hydraulic pressure testing.” Start with the main pressure first!
Ok boy that is a bit to digest. You guys are good. Ok so I’ll have to get back to you on the down pressure. The hoe is disconnected from the machine right now. I was going to test the front bucket to see if the pump is good. Boy l seem to have the order of things all screwed up. But next weekend I’ll put it back together and test the hoe some more. BTW l still haven’t gotten all the old contaminated oil out of the system. It was just a bit cloudy. So I’m draining that today. Then l have to go out of town for work. I’m only home on the weekend.
I’m only grumpy to young whippersnappers lol
Get the pressure and your hydraulic operations on your tractor within specs before you hook up the hoe.
Well l can relate I’m 60 and can get pretty grumpy myself. I’ll try not to irritate the guys who are helping me. Lol.
Thank you. So that’s where l get a little foggy Vtech, if l understand the book, l start with the l/O? Or was it the individual circuits?
Since you stated that all the hydraulic functions seemed weak, you need to check the main system pressure first. You need to check it in every function with the oil at operating temperature. I use a 6’ hose/gauge so I can sit in the seat to operate/bottom out the cylinders on each function.
Let me ask you something?! The spools of that red control valve that connected to a section you replaced port relief on - what control levers those linked to?
So l have a 4 ft hose/gauge and a helper. Lucky me. I’ll start there. Breakfast is over going to work. Will report back. Might be next weekend. You guys are great. I really appreciate the help.
Those are the outriggers.
And the section that red valve connected to? The one you replace the valve on?
Sorry! I got confused by the picture! The outrigger control valve is mounted against anti cavitation valve head, and looks like it is a fitting connecting two of those! Never mind!!!
No problem l appreciate that you actually know what they’re called. Anti cavitation refers to air in the line?
That’s the valve that prevents creating a vacuum when cylinder is moving too fast! It is opens up that side of the control valve section to return oil to replenish with oil and eliminate possibility of cavitation. Sucking air called “airation”, although those two kinda sounds similar when you hear them occurring!
When you took the hoe off did you connect the in and out hyd. lines back together so you wouldn't dead head the pump?
Yes l did. Thank you for asking. I’m out of town working will return on Friday night. And will get some of these things started.