What is the general procedure used to clean the hydraulic system on a piece of heavy equipment (dozer, excavator, etc.) after a component failure? Like a pump or motor failure that is suspected of having contaminated the system with metal shavings? Is the system completely disassembled and cleaned? Or drain the oil, flush the reservoir and oil cooler, new oil, new filter and hope for the best? Obviously a complete tear down would be best, but is it practical?
Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
Largest Manufacturing Technology Community on the Web
Stay Connected:
OT- Cleaning hydraulic system after major component failure
- Thread starter HOMESTEAD
- Start date
- Replies 17
- Views 8,737
Milland
Diamond
- Joined
- Jul 6, 2006
- Location
- Hillsboro, New Hampshire
What's the value of the system VS time and cost to replace? Any signs of contamination when you break hose connections to various components? Size of particles?
If I could not take the entire system apart, but wanted to clean things as best I could, I'd buy a cheap hydraulic pump and remote filter, and build some adapter hoses to allow me to disconnect elements of the system, attach the pump and filter, and cycle fresh fluid though with a few filter changes during the flush. Cut the removed filters apart, check for reduction of contamination.
When all the major elements and hoses have been flushed, hook it all up and give it a shot. You may have to cycle valves and even run the OEM pump to get the best chance of getting all the particles.
If I could not take the entire system apart, but wanted to clean things as best I could, I'd buy a cheap hydraulic pump and remote filter, and build some adapter hoses to allow me to disconnect elements of the system, attach the pump and filter, and cycle fresh fluid though with a few filter changes during the flush. Cut the removed filters apart, check for reduction of contamination.
When all the major elements and hoses have been flushed, hook it all up and give it a shot. You may have to cycle valves and even run the OEM pump to get the best chance of getting all the particles.
Machine in question is a mid 2000's Deere 332 skid loader. Wheel motor failed and owner is selling it as is. Sounds like one of the bearings failed. Shavings were found in the hydraulic filter. I would like to buy it to fix for my own use. The process of replacing the motor and hooking everything back up isn't a big deal. But if the whole system really does need to be taken apart and totally cleaned, then the machine isn't economically viable.
Milland
Diamond
- Joined
- Jul 6, 2006
- Location
- Hillsboro, New Hampshire
Maybe contact a dealer and ask a service manager what their procedure and cost would be for the work. That'll give you a better idea of what's involved, and whether it makes sense to pay for service or DIY.
What's the As-Is price?
What's the As-Is price?
G
Guest
Guest
You can use that to beat the guy down on price.
"Make offer"
seiner
Cast Iron
- Joined
- Jan 9, 2008
- Location
- Valdez, Alaska
is a return side filter? fix problem, change filter, run it
no return filter? don't buy it
no return filter? don't buy it
Strostkovy
Titanium
- Joined
- Oct 29, 2017
I would flush everything between the motor and filter, and disassemble and clean the valve, if it is easy to do so.
The pump, cylinders, and other motors would be the only thing I would worry about and I don't see how metal shavings could get to any of those.
The pump, cylinders, and other motors would be the only thing I would worry about and I don't see how metal shavings could get to any of those.
idacal
Hot Rolled
- Joined
- Aug 9, 2011
- Location
- new plymouth id
some pieces of equipment have an intake screen not very fine but doesn't let the big chunks back through if it has that and a return filter, make sure its a good deal price wise
hoses are easy, valves are easy, unless they got scarred, when I lost a motor on a drill rig I had 20 gallons of solvent with a pump set up on it and started flushing 3 days later I was done. the biggest thing is the oil cooler will have pieces hidden in it that dont flush out. wouldn't hurt to keep up on oil analysis afterwards for a few hundred hours that will let you know if something else is coming apart.
hoses are easy, valves are easy, unless they got scarred, when I lost a motor on a drill rig I had 20 gallons of solvent with a pump set up on it and started flushing 3 days later I was done. the biggest thing is the oil cooler will have pieces hidden in it that dont flush out. wouldn't hurt to keep up on oil analysis afterwards for a few hundred hours that will let you know if something else is coming apart.
edwin dirnbeck
Hot Rolled
- Joined
- Oct 24, 2013
- Location
- st,louis mo
BEWARE,SOME skid steers go forward and reverse by shifting a valve on the PUMP. This means that the wheel moter low pressure return oil,which might be contaminated is returned to the pump,thereby causeing more problems.Edwin Dirnbeck
BoxcarPete
Stainless
- Joined
- Nov 30, 2018
- Location
- Michigan, USA
If you intend to flush the system with a solvent, do your seals a favor and use one that won't chemically shred Polyurethane or Buna-N which are the most common materials used in hydraulic systems. If you happen to have any viton or teflon elements, they will likely be fine for the duration that it takes to flush the system.
Chemical Compatibility Database from Cole-Parmer
There's a link to a drop-down searchable chart from cole-parmer. I wouldn't use anything that was a "D" and I would reconsider a "C" unless availability was a big concern.
I would have asked over at www.heavyequipmentforums.com.....Duh
I deal with these situations often it’s how the system was designed. Most traction circuits are contained to only traction. Most use a squash pump. If the piston heads get scored the pump is garbage. Most systems filter on the inlet of pump to try and stop contamination of the pump.
What I would do is check the schematic and flush everything from the wheel motor to the pump. Fill unit and run then do a drain and fill plus new filters. Cut old filter for verification. Not bad to have a analysis after all done. Just had to flush a John Deere 320 engine because the f-in oil cooler had a internal leak and this is what my radiator fluid looked like when I checked it. Milk anyone. Some reason can’t upload photo. Had to flush coolant system with simple green to cut down the oil. Flushed rad. For 8hrs and change coolant after 2hrs of use. Back to green thank god.
What I would do is check the schematic and flush everything from the wheel motor to the pump. Fill unit and run then do a drain and fill plus new filters. Cut old filter for verification. Not bad to have a analysis after all done. Just had to flush a John Deere 320 engine because the f-in oil cooler had a internal leak and this is what my radiator fluid looked like when I checked it. Milk anyone. Some reason can’t upload photo. Had to flush coolant system with simple green to cut down the oil. Flushed rad. For 8hrs and change coolant after 2hrs of use. Back to green thank god.
kustomizingkid
Titanium
- Joined
- Aug 2, 2010
- Location
- Minnesota
Here is what I would do..
Drain main hydro tank and inspect for shavings.
Remove wheel motor and remove both lines going to the wheel motor and inspect for shavings.
If the tank has metal in it clean totally. If the lines have metal on BOTH sides then keep removing lines upstream and continue cleaning.
If there is metal present on either side of the traction pump, then pump out and disassemble and inspect.
Things are fairly partitioned in the system, but a keen eye must be used. Obviously replace all hydro filters and I would use all new fluid. Depending on the year some use hydro and some use 10w30 motor oil.
Drain main hydro tank and inspect for shavings.
Remove wheel motor and remove both lines going to the wheel motor and inspect for shavings.
If the tank has metal in it clean totally. If the lines have metal on BOTH sides then keep removing lines upstream and continue cleaning.
If there is metal present on either side of the traction pump, then pump out and disassemble and inspect.
Things are fairly partitioned in the system, but a keen eye must be used. Obviously replace all hydro filters and I would use all new fluid. Depending on the year some use hydro and some use 10w30 motor oil.
john.k
Diamond
- Joined
- Dec 21, 2012
- Location
- Brisbane Qld Australia
Hydrostatic system fail is a closed loop system......one components fail,all components damaged severely by circulating metal..............metal is not shavings,it is hard steel in very sharp particles ..........and the only way I know to clean the system is a complete stripdown and physical washout of every hose ,pump .motor,etc................if you fit one replacement assy,say a motor ,it will quickly be wrecked by steel chips......................this is the reason why you can buy a high hour Caterpillar 963 for peanuts,when an old D7 G or D6D costs a fortune......they are mechanical drive.