I have a John Deere 310c Backhoe Loader. 2 wheel drive. No turbo. OROPS cab. It has roughly 8000 hours. Owner operator since 1995. I have never had any issue with the hydraulics except hoses, and a few cylinders rebuilt. I only use it about 10 times a year in past few years. Random small jobs or unloading stuff from trucks around my shop. When it was last used a year or two ago on a septic sewer system for a house, i blew the main hydraulic hose under the tractor. It was a big line that feeds the main valve body. When it blew, I cut the machine off. I replaced the hose. Refilled fluid, and it operated good. I noticed it wasn't optimal and so i then replaced the hydraulic filter. That seemed to improve the situation. Over some time, It seemed to not be optimal again. I made sure to pull the screen in the hydraulic tank. I dont know what is considered clean or whatever but its a metal screen and i washed with gas and it looked fine. Then i noticed intermittent weakness in hydraulics. I noticed that the main suction line from the tank to the pump looked weak and collapsed in one area. I replaced the main suction line. This made a great improvement. After some random use around my shop, i noticed the hydraulics were just not that optimal. I rebuilt a few leaking cylinders. I rebuilt the center bucket curl cylinder and then the main boom it cylinder. This seems to mildy help things. Then, i noticed the steering cylinder was pouring fluid. I let it leak for past 6 months when randomly using backhoe around the shop to unload stuff off of trucks but always made sure the hydraulic system was never low. I could hear the steering cylinder sucking air after cutting off engine. So, i thought, i bet im getting air in the hydraulic system. I rebuilt the steering cylinder. cylinder works good. Now, i have the same weak hydraulics. I am about to put on another expensive hydraulic filter for the millionth time. Just to eliminate the possibility. Is there a screen inside a main line somewhere under the machine that I don't know about? Not the one in the tank, but somewhere else? I saw a youtube video where it showed a 310a or 310b that had an inline screen somewhere down under the machine that is hidden behind the filter base. If, there is not a hidden screen and this current hydraulic filter change doesn't do anything, what can i do? Can I test hydraulic pressure somewhere? How? I am a poor farmer type person and I really need to go the cheapest route. I have a few hydraulic gauges in my shop but I don't have a clue about adapters, or where to check it, or what to do. I don't have a full on service manual and i really only have a basic parts and operation manual. To be honest, I can't really even afford a service manual right now. I have some work for the machine and I am in a bind on what to do. If the hydraulic pump is bad, should i pay john deere 4500 for a new pump? I found a used one online for $750, and a few aftermarkets pumps for $2500 on ebay. Are these pumps rebuildable? Can i rebuild one myself? I do have a machinist friend for some mild help.... Any ideas and help would be appreciated. Im just a small time dirt mover and farmer. Thanks!
No idea what may be wrong Bill but also make sure the hydraulic tank vent it clean . I would say the pump is rebuildable never rebuilt one but the last pump I bought was a rebuilt for $180 same price as the kit. I'm sure they are much more now though that was a few years ago.
I wonder if your relief valve is sticking? That might explain the burst hose and coming and going weak hydraulics. I'd take it out and check for scratches, broken spring, etc. You're going to need to get the adapters and pressure gauge, or borrow them, might as well check the pressure before you check the relief valve, then after to set the relief valve. Another thing you could do is start the backhoe on a cool morning, work it reasonably hard without stalling any function for several minutes, then see if any parts of the valve feel warmer than the rest, and then see what that warm part does...
Hi. You bought a pump for a 310c specifically or a backhoe in general. For $180? After searching my junky old shop...I have realized that I have what is called a John Deere technical manual for my 310c. In it, it makes it look like the pump may be rebuildable but does not say? It shows the disassembly and inspection of pump process. And removal process. So, I’m not sure if it can be rebuilt or not? I’m assuming but it may be that parts aren’t available. Another odd thing is that the technical manual lists 2 brands of pumps: Vickers and Sunstrand/Sauer. Heck, not sure what I have? I think the Vickers looks more like mine. Also, they seem to call the hydraulic pump the steering pump? Is that just because the backhoe does not have a separate pump for steering? What a vague technical manual!! And, the relief valve seems to be next to the loader valve body. Hmmm. I don’t want to buy anything from my John Deere dealer I’d possible. I’m not too happy with the dealer prices and dealer performance around these areas. They do have have some nice and helpful mechanics occasionally(via phone).
You make a good point. Would this explain my weak lift and dig performance? You have a good idea about the heat seeking approach. I have a thermostat gun. Could I not point the laser at the valve body versus the relief valve and write down temperature of before (when cold) and after(when hot)?
Don't write off the deere dealer, they're the only and cheapest place to get some stuff. Yes, a relief valve that's sticking closed can stick open also and cause both the blown hose and poor performance. I can't think of how a weak hydraulic pump could blow a hose? The before temp is going to be the same cool temp as everything else, you want to find what is hottest right when you shut it off, and then find out if that should be hot or not. Don't be afraid of adapters either. This place has an id guide to help figure out what threads you need, your technical manual will have them listed too. And they'll have the fittings to make up whatever you need to do the test. https://www.discounthydraulichose.com/free-thread-id-guide.html
Thank you for the reply. I will do what you say regarding checking for source of heat. The relief valve, if is the issue, should be rather cheap right? What is strange is that my technical manual does not say anything about checking hydraulic pressures. Unless I have overlooked somehow. Odd. It also alludes to a potential pump rebuild but disguises it as a quick inspection of gears and wear and resealing.
Welcome to HEF BillFold ! Did you save any of your filters so you can cut one open? That is the first thing I would have checked. Just to clarify, is it all hydraulics that are intermittently slow and weak or just the backhoe? Also machine serial numbers on Deere equipment are a must. Your machine has two different parts suppliers based on a serial number break. Regardless of the serial number the pressure test should be roughly the same (see attached).
Yes, Our 310C does not have a separate steering pump or section. It has a priority valve, located under the cowling, toward the rear of the engine.
Thank you so much for the PDF. Do you have a way to tell me what pump I have based on my serial number? I have a technical manual but no parts book. Go figure. Technical manual doesn’t come and say if I can rebuild my pump or how. But it shows me how to take it apart and inspect and regasket. One thing in wondering.... it shows the relief valve in a block next to loader arm control valves. Is this considered the “main” relief valve? After I change the filter I’m going to: 1: Save the old filter and cut it open. 2: run machine to see if new filter makes a change. 3: after machine is cool...run machine and use my thermal laser fun to record temps or various valves, pump, etc.... 4: take the relief valve out next to laser arm and inspect. - The machine is weak when it comes to lifting the loader arms up high, the strength or backhoe digging, and the stabilizers don’t lift the machine off the ground very far. No noises. Transmission works great.
I cant see around the front counter weight very well but the pump looks to be the Sunstrand/Saur version because it has an opening in counter weight for a pump relief valve. The technical manual says it is not adjustable or repairable. So this is an additional relief valve? Hmmm. I guess when considering the age of this machine, I might should replace this relief valve? Any tips on cheapest place to order? Also, is it dangerous to remove? Pressure in system? Thanks.
Here is an excerpt from technical manual about the pump relief valve. And a photo of my counter weight with relief valve access hole through counter weight(indicating a Sunstrand/Sauer brand pump).
I am mistaken … There IS a separate steering section.
Whether it is a Sunstrand or a Vickers depends on the serial number of the machine. 748119 and down have a Vickers and 748200 and above have a Sunstrand. Yours looks like a Sunstrand because the relief for the steering is on the front. The Vickers steering relief is on the side of the pump. There are two pumps behind that counterweight. What you see from the front is the steering pump and the main hydraulic pump is behind it. Yes the main relief valve is on the loader control valve. You will need to check main relief pressure first.
Agree, with pressure releif valve , find it and remove it. Make sure it is clean. Will be a spring and a poppet. When pumps go bad they will work the best when cold, and the worst when hot.
Ok. Had a long weekend away and back to this project. I installed the new filter and operated machine. I noticed about a 10% improvement in instances such as: stabilizers didn’t not lift machine but I could keep quickly snatching the lever and it’s would raise a few inches each time until fully extending. What I notice is that I have to rev the engine up to get loader arms to move. So when heading toward a dumptruck to dump dirt in dump truck bed, the travel speed doesn’t match the loader arm speed so I have to stop in neutral and rev up engine. I past, this operation was in sync. When backhoe boom lift gets near the end I hear a light strain on machine. This strain also occurs for most other functions on machine as well. Next step is to relieve all hydraulic pressure by wiggling handles and making sure all cylinders have no gravity or pressure and then safely and slowly remove main relief valve for inspection.
The screw driver indicates the relief valve. Also, what is the inline fuel filter looking thing that appears to be coming from the tank vent? There are two tiny fuel line/hose size rubber lines coming from hydraulic tank. One goes up to the fuel tank area and one runs out under floorboard to somewhere?
So I took the relief valve apart. It did seem kinda sticky in the little end where you might pop a screwdriver against it to open it. But a few jiggles and it was ok. But it could have been fluid pressure internally as once I popped it it leaks a little. I took it all apart and inspected it. Looks clean and smooth. But I think I messed up. I removed the upper cap that has a jam nut. I assume that’s how you adjust the relief valve pressure? Now I have no idea how to adjust the pressure. Where do I put a gauge? My technical manual does not say.
Ok. So, I installed the relief valve back onto machine. It still acts the same. But now, I have no idea what pressure I am at. Maybe I have the cap adjusted too weak? My service manual does not explain how to check hydraulic pressure or set relief valve. So, today I called my Deere dealer. Flint equipment braselton. It seems that: They don’t have any relief valve available. All discontinued. The only relief valve available are for the loader control or backhoe control. The parts guys said that the original relief valve was a Husko brand (what I have) and Deere updated the part but even the updated valve body and relief valve is discontinued. What???? He also said that he can’t see any info on his computer or where or how to check pressure. His computer shows no adapter or anything for hydraulic testing. He says I will need to talk to a Deere mechanic and maybe the mechanic can look up the “tooling side” of Deere computer to see what is needed to check hydraulic pressure. Mechanics leave early every day? Will have to try again tomorrow. Parts Guy says that the hydraulic pump from Deere is $4600. John Deere 310c hydraulic pump part number is AT114134 . He says the computer shows a rebuild kit for hydraulic pump rebuild kit part number: AT124365 . The kit is $135.00. He says the rebuild kit is only 5 o-rings. That’s a rebuild? Wouldn’t I need to two gears and shaft and such to rebuild a worn pump? My pump is a Sunstrand/Sauer pump. The steering pump seal kit is part number: AT124228 and is $131.43 . It’s a seal kit. It included relief seal but not relief valve. The relief valve for the steering pump is part number AT124227 and it costs $370.46. Lol. Wow. As far as the main relief valve, there are three psi version my backhoe could have: 3500, 2750, and 3800. That must be the main, then one for loader and one for backhoe. He didn’t know? So Deere officially sucks in the parts and information department. The parts guy was nice. But he seemed to have limited parts and info from Deere. Where would I find out how to test hydraulic pressure properly? Who to ask? What to buy? I have a few gauges but no adapter or don’t know where to hook it. I did find an original style relief valve for sale on eBay. Maybe mine is bad and I can’t see the wear internally? Mine looked ok... Thanks
This is an original part number relief valve as seen on eBay. But how do I know if I need it really? Also, why did Deere upgrade the relief valve assembly away from the original Husko brand like I have? Maybe I need to update mine but where would I buy one if Deere can’t sell me one?
If all else fails just put a tee in a pressure line with a gage on it. Once you know the pressure it’s running at you can make adjustments or determine if the relief valve is bad. That looks like the type of relief that has a pilot valve adjustable with shims.
Thanks for the reply. So, I could theoretically just put a t in one of the hoses going to the loader lift arm? I have some pressure gauges but no adapter to fit this machine. This backhoe has the deere taper fitting looking connections. I cant remember. What are they called? I live in a small town. Where would I find a t that fits between a hose and the loader lift arm? I find it odd that the relief valve housing doesnt have a dang port where you can use a pipe thread nipple to mount the gauge? I used to do that on old Case backhoes back in the day.... I doubt my local NAPA has any kind of line T. Grrr.... So, when i do test pressure, and it shows low, i add or remove one of the two shims? And if that doesnt help then i know its the relief valve or the pump? Or, should i then replace the relief valve anyways before i consider buying a $4600 pump? Thanks so much
No normal test ports.
Maybe I could find some sort of a T to go in one of these lines to the loader loft arm cylinder? But would I have to have the loader lift valve open using the joystick to see pressure reading?
Wrench size is 15/16. Can’t remember name of fitting style. JIC?
The size really doesn't tell you what the fittings are. Those don't look like JIC connections to me but might be. It's always best to remove them and see what they are. Does the technical manual have a hydraulic diagram for this tractor? That would be the place to start. Locate the high pressure line coming from the pump and find a convenient spot to splice in a tee. You may have to visit your dealer to get the fittings you need unless you have a hydraulic shop near. If you can watch the pressure while working the machine you may be able to diagnose the problem.
Thanks for the reply. It my logic, it seems as though I’d wanna splice into the main pressure line before it goes into the block where the relief valve is located. And then move the t to the outlet side of the block that is AFTER the the relief valve. But as far as the AFTER or outlet side of relief valve block, i assume the accessible outlet side of the block is a return to the pump. So I’d be better off moving the T and gauge to a like coming out of the loader valve and cracking a joystick valve to see pressure when valve is open. The return line to pump would show ...well...maybe I would want to know that pressure as well. My service manual leaves out the hydraulic circuit diagram. Odd huh? But luckily, the hydraulic system is kindof laid out simply on this machine it is a basic 310c with no extra features. So, I yet to understand why there is a mystery as to what is considered a rebuild of this pump. A 5 Oring kit from Deere is what they call a rebuild kit. So, no gears or anything within the pump are needed for a rebuild. An interesting thing I notice when my machine is running there is this pulsing vibration/ harmonic sight feeling I feel in the machine. It’s a pulsing thing that almost feels like something is out of balance in the the pump that pulses in and out in 1 second pulses. It doesn’t seem to be the engine.
Post # 8 has the procedure and fitting sizes which connect to the port below. And yes, the relief valves are obsolete through Deere. You will have to source them elsewhere. Google search AT118707 for serial number 752244 and down, or AT117647 for serial number 752245 and up.
Omg! You are a lifesaver! I literally was looking back at my pics and just was gonna post a post asking if that spot could be it! I don’t know how I overlooked it when I was physically in the presence of the machine but I was looking back at the pics for the “Husko” brand and part number and googling why or what the upgrade was and the thought hit me! Could it be and boom...u sent your reply! I guess I may have originally thought that weird spot was part of the assembly or where it connects to loader valve assembly inside...o ring access or something. I saw where you had marked on the photo and I just tried to mark on the photo using my iPhone. I didn’t know marking on a photo was so easy. I learned multiple things from your reply! Thank you! You must have lots of experience. Idk why Deere has left these old machines out to pasture on parts. I thought the whole reason for buying a brand like Deere was because of parts availability.... Forget that. Shoulda bought a dynahoe lol Here is my attempt at marking on a photo:
I’m so stupid I didn’t realize you had sent me the info back in the beginning! The PDF!! So I’m googling the adapters. Not sure if I need one or both. Haven’t found the on eBay, Amazon, or google yet. Must be a Deere item? So I must pull that plug out and install adapter and then thread a standard hydraulic pressure fluid filled gauge in. I have some 0-10,000 psi gauges and some lower psi gauges. I last used them on a d3 cat pedal steer diagnosis situation. No quick couplers...just raw gauge with brass nipple sticking down...
Those fittings are Deere part numbers. If you want to source those fittings elsewhere try looking using the fitting sizes. Forgot to answer your question on the little filter, yes that is a tank vent. The filter just keeps dirt from being sucked into the tank when the tank is "breathing". As far as obsolescence, I think they do that so you buy a new machine. When a machine gets to certain age (it varies) Deere stops supplying/making parts.
I think what you want can be googled using 6400-4-4 fitting. You can then look for a diagnostic coupler to connect to it or just connect a hose directly from your gauge to it.
Well. I finally got the adapter. It took two tries on amazon. They sent the wrong part. It’s a 6400-04-04-0-SS
So, according to the service bulletin, it says to check pressure at fast idle. I’m getting 0. When I crack the loader valve joystick it raises slightly on the gauge. I backed the top cap off on the relief valve further than what seems normal. No change. Also, does the relief valve factor into this test port? It seems that if it’s coming from the main inlet it would be just pump pressure. But I’m a way I can see how the relief valve may stick down into the body to where the port is and move flow toward the outlet or back to tank? Hmmm.
Thank you so much for the tip. I tried to do what you said. All I could get was 1200psi. I adjusted the relief valve. No change!! I tried to be safe about the adjustment. I’d cut engine off relieve pressure on hydro system and then turn the top adjustment cap one round wash time. Then crank it back up. No change each time. Here is the embarrassing part... I walked away for a second to pick up a wrench or something...all the sudden the hydraulics shot out of relief valve! The top cap must have been on its last thread of adjustment and vibrate loose shooting fluid all over my shop! Luckily I wasn’t near it but it still got all over me! I couldn’t get to the switch! It was spraying over it. I had to grab a steel bar and ready I’ve into the cockpit and bump the ignition key off! Omg what a mess! Well, seems to me the relief valve isn’t adjusting pressure properly. I ordered the one and only that I could find off of eBay! Waiting on it to come. Ok, so this may be an undiagnosable relied valve issue? It looked fine when I took it apart to clean it. But also, what in the hell is the weird pulsing sound and vibration this thing makes at high rpm. Engine seems fine. Some kind of pump surge.... And by the way. I’m so frustrated with the dealer. The parts guy can’t sell me fittings or tools. That has to be sold through the machine sales. The machine sales guys don’t answer the phone and when one does..he doesn’t have a password to log in to the tooling sales website??? Only one guy has that password and that guy can’t be found. Everyone at Deere tells me to call parts. Parts tells me to call sales. Sales tells me to call parts. Parts tells me to call shop service. Most parts are discontinued! And so, if my pump needs to be rebuilt...John Deere’s rebuild kit is only orings and seals. No hard parts. I look online all over for Sundstrand Sauer hard parts for pump and can’t find anything. Only lawnmower stuff. What a mess. Where does one find Sundstrand parts? Thanks for the help so far. Waiting on relief valve.
At this point I have to advise you to STOP! it is time to hire a professional whether it be the dealer or an independent to do an evaluation of your pressure and flows. Thank goodness it was only an oil bath. It could have been worse.
So what was the culprit of your issue?
Looks to me like you also have circuit reliefs did you check pressure at a function that you say is stronger