Hello, We have purchased a 2010 NH B95B backhoe with 1,700 h as is and the rear hydraulics don't work but the front bucket, forward, and reverse works as it should. After we got it I did some testing and the outriggers would only go down but are very weak and would not lift up the back of the tractor at all and would not come back up. Also the hoe was moving very slow side to side and would slowly go down but won't go up and bucket would slowly crawl up but not open. I have found that the hydraulic fluid was a bit milky, so decided to change all of it, but that didn't make anything better. This is my first time owning a backhoe, so I don't know much about the hydraulics and what could cause the rear hydraulics not to work properly. Any help would be very much appreciated! Thank you.
Welcome Al! You've got the big brother to my lb75b! 1700 hours (if the meter works) should be a baby! Let's see pictures! Only thing I can tell you, as I'm inexperienced as well, is for better or worse, I can say that somewhat milky hydraulic fluid should not have too much effect on operation, unless you have a burnt up hyd. pump. Mine has milky fluid and still runs pretty well. I've changed it out once but it was still stored outside and it milked up again. I haven't had the time or money to change fluid again, now that it's stored inside. Also, if you didn't get the old fluid out of all the hoses it will be contaminated again, very quickly. You've come to the right place, folks here are very knowledgeable and helpful!
Welcome to HEF, Al ! I don't have any experience on New Holland machines, so I can't help with the backhoe problem. But, milky looking hydraulic oil is almost always caused by water intrusion. The only way to get rid of it is doing a complete system flush. Changing the oil in the reservoir is a waste of good oil. There is no way to determine how much water is in milky looking oil that I know of. You can run it with that crap in it, but there is no way of knowing how much damage is being done to the pump. If and when the pump fails you have system full of contaminated oil that could be really bad going into a nice new tight pump. The price of a new pump and the oil lost when it fails could buy a lot of oil to do the flush.
Thank you aighead , I didn't put new hydraulic oil knowing that it will get contaminated again, I just left it in the garage for a couple of days for water to separate on the bottom and then pour it back carefully not to add that yellow sediment back in. Also I heard people boiling it to evaporate the water.
Here are some hydraulic system diagrams
If anyone can read the diagrams maybe that could help.
If you had it separate nicely you may have gotten lucky and it didn't mix too much with the oil. I don't quite understand the physics of it well but as I understand it there is a point where the water molecules mix too thoroughly with the oil particles and they won't separate out. I suspect my machine is in that realm. I need the gumption to get back into the operation of a complete flush again. I've heard of the boiling trick to varying success. The best method seems to be a filter cart but those are big money if you don't have one or know someone. I'm really talking out of my backside (in the hope that someone smarter comes by) but I believe there is a big bank of valves (if I'm recalling properly it's all one block with several inputs and outputs), just under the hoe side window, that controls flow to the hoe and stabilizers. I wonder if there's a restriction going to/fro that valve? I don't think I can see your pdfs where I am right now, but a good chance I wouldn't understand anything with them anyway.
aighead; You are right about the water mixing with the oil. You not talking out your backside about the valve bank. Al has either a restriction or for some reason the the oil supply to the hoe is being diverted to the hydraulic tank. His problem is tough one to figure out without being there to do some hands on checking.
Hey! I got one!
Maybe I have found something. After aighead mentioned about a big bank of valves, I went under and started tracing all the hoses and this caught my attention (see pictures). Don't know what it controls, but the blue sensor part that screws in on that threaded tube on the first picture was not tight and the wiring protection was broken off from it. it's located on the same side as hydraulic tank, above the rear axle. I can see the bare wires deep in there. in addition the washer on it is bulged. I will start here, find the replacement, put the new one in, and see if that helps. Thank you for all your ideas!
There is no way my ignorance actually helped someone here, so I wish you luck! I'll be very pleased if it actually did, but I won't believe it. I'm just here to learn!
So After Installing a new solenoid, it didn't help. I was working on and off on it while still renovating our house and fixing our farm tractor. It took forever to remove all those hydraulic hoses to remove the LOADER CONTROL VALVE assembly.
I was expecting to see a blown oring in one of the valves. But to my disapointment after taking every component appart and carefully inspecting them, I dont see anything obvious. All seems to be looking ok. I know all parts need good clean up before reassembly.
Has anyone encountered something similar? All has begun with the backhoe barely moving in all direction while the front loader bucket and transmission working great.
Could a hose be collapsed not letting enough oil flow to the backhoe valve?
@ Ai D You are a brave man for disassembling that "thing." I hope you took a ton of images to help guide you through the reassembly.
You poor soul! You've been at this almost a year and haven't figured it out. I can't make a lot of sense out of the diagrams you posted. I have a hydraulics training manual for the E series but I'm afraid it doesn't correlate to the B series and might muddy the water on your quest. I will post it for you to look at but be advised it may be completely different than the system on your hoe. I saw some manuals on your series on eBay. Maybe someone on here has one they could send you.