flushing hydraulic system

[Rick in WA]

My Jinma 284 hydraulic fluid had some water in it and needs to be changed out. I have read others say to use kerosene in the system to flush out the crud, but just trying to verify the proper procedure to do it. I am assuming draining out all the fluid, and then adding a couple gallons of kerosene, and then running all the hydraulics to flush everything out. I just have some back of my mind thoughts about running kerosene through the pressure pump, being as kerosene is a little volatile.
Any enlightenment would be appreciated.
Thanks, Rick

 

[LouNY]

I would not run the tractor with any kind of flushing fluid. My personal choice is diesel fuel.
You can disconnect lines and back flush them with gravity, or disconnect and flow good hytran fluid through the system to purge and clean them.
I dump a few gallons in the housing and the rock the tractor back and forth the more vigorously the better, then drain you may even repeat it a couple of times.

 

[piper184]

Personally if all I was worried about was water, I would drain and refill the tank. Then run it for awhile and check for water in the fluid. If found, drain and replace again.

If you keep the drained fluid in a clean bucket it may go ahead and separate out with the water sinking to the bottom. Then you can decant off the good fluid.

I would be reluctant to run any solvent through the system as it is not made to lube the parts and might actually cause harm. I would only use a solvent on something that was taken off for repair so that the rest of the system didn't get solvent in it.

 

[Rick in WA]

That was my concern also. I had just noticed that the kerosene flush showed up more than once, but was cautious about it. The gravity flush sounds good, but not sure how to get it through the FEL, the steering, and three point.
I have already drained the sump and refilled, but there is enough in the rest of the system to still be milky, which is causing issues with all of the above.
I think I might lift the fel all the way up and block it, and then run the levers to get most of the oil pushed out, and then do another drain. is there any kind of additive for water block you can put in hydraulic fluid?
Rick

 

[Bob Rooks]

I would only consider flushing with a solvent (diesel fuel) in the case of contamination with dirt and/or grease. Water and oil are miscible, so just change it or filter it. I conjured up a unit that does just what you want. All you need is a little gear pump, and a Goldenrod filter. I use it for fuel and hydraulic oil. You just put the inlet and outlet hoses into the sump and turn it on. It recirculates as you cycle the system. Change filter elements often.
Piper's decanting proposal works equally well but will take time and space. The specific gravity of water is heavier than oil so they will separate. I use that method with the chain case oil in my skid steer (the finest metal particles separate).

 

[Bob Rooks]

You can also get one of these units if you have the resources. We had one on one of the ships I worked on. Worked like a champ.

Fuel & Hydraulic Oil Tank Sweeper Polishing & Filtration System | Innovative Products of America

The Fuel & Hydraulic Oil Tank Sweeper® is a mobile filter cart for cleaning, transferring & filtering water & contaminants from fuel & hydraulic oil systems.

ipatools.com

 

[Rick in WA]

Thanks for the replies. My brother drained the oil out of his trackhoe and we put it in his crab cooker and heated it slow until about the boiling point of water, and managed to boil it out. I most likely will try draining it again and running some new fluid in, as I also need to change to a lighter weight oil. Pretty sure it is 46 in it right now, which from what I have read is too thick for this unit.
Rick

 

[Bob Rooks]

You just got some of the water out with the crab cooker, but with a small system I guess it isn't that important. I'm used to working with 300 gallon systems that have very many expensive components, but here's a good read anyway.

How do you remove water from hydraulic fluid? | Sealing & Contamination Control Tips

Various types of contamination occur in fluid power systems: gaseous (e.g. air), liquid (e.g. water) and solid contaminants. Focusing on water, this type

www.sealingandcontaminationtips.com