480e hydraulics

At idle all i hear is engine noise. With the engine rpm @ 1500 the hydraulics are loud/whining at rest or during operation, at max rpm hydraulics quiet down significantly. Bucket controls seem to jump at any rpm while all other controls are smooth. Replaced hydraulic filter with no change, pump coupler seems good with no play. Any ideas? Backhoe was used very little for the last 20 years until I purchased it from a cemetery. Thanks for your assistance.

Any possibility a stabilizer or boom or dipper rod or valve is stuck up or anything else, causing continuous flow that self centers with higher RPM? When you shut off, is there pressure when removing cap? What kind of filter did you put on and how did the old one look? Have you checked at 1500 RPM, if any cylinders are getting hot? Does this unit still have the anti-rollback rod and self leveling solenoid and do they work? Is this with the boom locked?

HarleyHappy said: Any possibility a stabilizer or boom or dipper rod or valve is stuck up or anything else, causing continuous flow that self centers with higher RPM? I’ll check on that, nothing obvious during operation and all controls work correctly. When you shut off, is there pressure when removing cap? No pressure at the hydraulic tank dipstick if that is what you are referring to. What kind of filter did you put on and how did the old one look? Donaldson case equivalent. Old filter seemed ok I did not cut it apart to check. Have you checked at 1500 RPM, if any cylinders are getting hot? I’ll check next time I run the machine. Does this unit still have the anti-rollback rod and self leveling solenoid and do they work? It’s a 1986 case 480e so I don’t know if it has these features or where to look for them. Is this with the boom locked? Same condition whether boom is locked or not. Click to expand... Thanks for the reply, see my answers above. I don’t want to run the machine and blow something up. The shuttle solenoid was unhooked when I bought the hoe, I believe because the floor switch was stuck in the neutral position. Which I fixed and hooked the solenoid back up so I can now shift gears while moving. I don’t believe this would cause the noisey hydraulics as when I have the transmission in neutral or in gear i can shift between forward and reverse with no change in the noise.

Not sure on the 480E but my 580 SE and most other backhoes I have worked on have a constant pressure on the hydraulic systems to keep the pump fed under return oil. Is it just a dipstick or a screw on sealed dipstick? Is the boom in travel lock and could you have a cylinder bypassing and creating continuous flow, check for heat in the cylinders. Is the hydraulic noise the same as when you hit the pressure relief valve? When you say bucket controls are jumpy, we talking loader or backhoe?

HarleyHappy said: Not sure on the 480E but my 580 SE and most other backhoes I have worked on have a constant pressure on the hydraulic systems to keep the pump fed under return oil. Is it just a dipstick or a screw on sealed dipstick? Screw on sealed dipstick, no pressure when removed. Is the boom in travel lock and could you have a cylinder bypassing and creating continuous flow, check for heat in the cylinders. I’ll check. Is the hydraulic noise the same as when you hit the pressure relief valve? No. The noise is similar to cavitation or a ford truck power steering pump if you know that type of noise. When you say bucket controls are jumpy, we talking loader or backhoe? Only the backhoe bucket, acts like it’s air bound, not enough flow, or something. All other controls are smooth and no noise. All controls have power and operate correctly. Click to expand... I will be at my cabin where the backhoe is located this weekend maybe I can take a video of the noise.

kyaabo said: The shuttle solenoid was unhooked when I bought the hoe, I believe because the floor switch was stuck in the neutral position. Which I fixed and hooked the solenoid back up so I can now shift gears while moving. I don’t believe this would cause the noisey hydraulics as when I have the transmission in neutral or in gear i can shift between forward and reverse with no change in the noise. Click to expand... Pretty sure shuttle system is similar to 580C and has nothing to do with hydraulics. What did hydraulic fluid look like when you changed filter? If full of moisture after sitting for 20 years, something could be rusted and sticking, Agree maybe some function may be stuck affecting other functions, heat checking could help diagnosis. Check and lube the crap out of all the linkages and make sure they're all returning to center.

stinky64 said: Pretty sure shuttle system is similar to 580C and has nothing to do with hydraulics. What did hydraulic fluid look like when you changed filter? If full of moisture after sitting for 20 years, something could be rusted and sticking, Agree maybe some function may be stuck affecting other functions, heat checking could help diagnosis. Check and lube the crap out of all the linkages and make sure they're all returning to center. Click to expand... Yes shuttle is separate and I have serviced all fluids except for the hydraulics. Hydraulic fluid looks clean. Hoe was used about 100 hrs in the last 20 years if I recall (i have full records since new up at the cabin), so yes something could be bound up from sitting. It’s in really good shape with just over 3000 hrs on it. All controls move freely and appear to return to center. There is a hydraulic screen that can be serviced but you need a special case tool to get to it, according to the service manual that came with the hoe.

So you do have manuals, good deal, you're miles ahead of most other guys with a "new to me" machine. Keep posting with results, lots of guys here with vast amount of knowledge, you'll get 'er figured out.

Thanks for your advice. I have a few things to check next time I fire it up, it's been very wet in upstate NY so far this spring.

Be aware, if certain seals were leaking, you could have water in the hydraulic oil and would look good from the top but in 20 years, there could be rust in certain areas. Just went through this in a skid that hadn’t run in 10 years.

HarleyHappy said: Be aware, if certain seals were leaking, you could have water in the hydraulic oil and would look good from the top but in 20 years, there could be rust in certain areas. Just went through this in a skid that hadn’t run in 10 years. Click to expand... It’s been run monthly just not much for the last 20 years, only used when digging a grave at the cemetery. Changing the hydraulic fluid is on the list to do eventually.

No time to run the hoe this weekend, but further research indicates it could be a failing coupler between the engine crank and hydraulic pump? When I get a chance I will remove the front grille and inspect the coupler for play.

Also check the suction hose on pump for condition and loose clamps.

Planning to run the backhoe tomorrow. While checking fluids and greasing this evening the hydraulic tank seemed to have "pressure" when I removed the dipstick... the machine has been sitting for almost a month, not sure if these means anything or not? I'll try to take a video tomorrow of it running and the hydraulic noise to see if it seems normal or something to further investigate.

Coy Lancaster said: Also check the suction hose on pump for condition and loose clamps. Click to expand... suction hose and clamps look intact

Watch unnamed | Streamable Watch "unnamed" on Streamable. streamable.com video of hydraulic noise. Tach is just revving the engine in neutral with no digging. Sound is the same when operating the controls, backhoe bucket doesnt operate as smoothly when curling as the other controls do. “almost” acts as if there is air in the line for the bucket at times. Backhoe digs with power and will pull the machine with any of the controls when off the ground. Maybe the noise is normal? It’s been a while since I ran a 1980s vintage case backhoe. Operated the machine for 3 hours with no issues other than the noise.

Check out all of your clamps on your metal lines. Sounds like there is a line vibrating under machine. Line may be rubbing on frame somewhere.

Odd noise, have you put a gauge yet on the hydraulics. Almost sounds like your filter is in bypass. By chance, is the pump out of center and can you verify if the noise is coming from the pump. Get underneath by the pump and have someone do that range of RPM again. While under there check for movement from the front motor mount.

Coy Lancaster said: Check out all of your clamps on your metal lines. Sounds like there is a line vibrating under machine. Line may be rubbing on frame somewhere. Click to expand... I'll take a look.

HarleyHappy said: Odd noise, have you put a gauge yet on the hydraulics. Almost sounds like your filter is in bypass. By chance, is the pump out of center and can you verify if the noise is coming from the pump. Get underneath by the pump and have someone do that range of RPM again. While under there check for movement from the front motor mount. Click to expand... How could I tell if the filter is in bypass? The filter was just replaced. Have not measure the hydraulics. What type of gauge would I need and where would I put it on the system? I can take a look underneath, I don't have anyone up here with my to run the machine though.