ATF for flushing water-contaminated hydro fluid?

[Coyote machine]

I'd be cautious about using a spin on type water separation filter, because of the pressures involved in the hydraulics are more than that type of filter is likely designed to handle. If you could use on the low pressure side of the system, probably not a problem. I think it is worth a try to try and 'dry' the oil this way. Those filters are used a lot on boat fuel systems, and work well to remove water in the fuel. Not sure you'd get one to remove the 'mud' you're dealing with but maybe trying it is the best way to find out.
Good luck, and remember to keep away from any hyd oil under pressure.

 

[glastron23]

crashcup.. we do this to all of the bucket trucks when we do their annual inspections. the lifts have to be no conductive so the oil has to be free of moisture since that could/will cause a path for electricity to follow. you will have to get a filter head and a hose that will connect to the tank/out port on the valve bank to the in port on the filter head, hook the factory hose to the out port on the filter head. just run the system normally. the filter that i showed will do the job, the filters we use (3) filter the oil to 3 microns and remove moisture, they cost about $125 each, these are overkill for your problem. to test for water you can do a crackle test. just take a sample of about 6 ounces, an old pie plate, a temperature gauge and a torch. put the oil in the plate, angle it so it pools in the corner and heat the bottom of the pie plate. when the oil gets to about 220/240 degrees if water is present it will boil and crackle(you will see it bubble) in the plate be careful ITS HOT.. Jim

 

[Gale Hawkins]

not a waste of alcohol...

alcohol is a polar solvent. water is polar. adding alcohol to a wet sump will disolve the water so that it can be flushed out ( drained ) in SOLOUTION not suspension, as with regular detergents.. or simply mechanical expulsion.

here's why the atf= solvent=alcohol mix works decently.

1, aft is a good light weight oil that is pretty universally compatible and won't damage anything in a hyds system. it has detergents too.. so some debris will be carried out during the flush in suspension.

2, diesel/mineral spirits / kerosene is a good mild petro solvent. it will thin the mix and makie draining easier and faster and have a better chance of getting stuff out of a sump.. including thick stable emulsified oil/water slime that may be sticking to walls of the sump. the diesel or kerosene shouldn't be a problem.. if it is, then millions of dollars in heavy equipment and tractors at my day job ( general contractor ) and my home farm, have been lieing these past decades we've been doing it.

3, when you add alcohol to water you get something new. an azeotrope. an azeotrope will actually flash off FASTER than either of it's constituants will. thus adding alcohol to a wet sump will help it dewater FASTER than just running it and waiting for it to flass off via heat alone.

look at commercialproductgs that do this. transtune seafoam. read the MSDS.

to the op. do whatever you want. not my machine.

running water in a hyd system will lead to cavitation . cavitation will lead to degredation of all the parts in the system that costs lots of money. like PUMPS.

I have used both regular and Transtune Sea Foam in the backhoe that helped some. The fact the alcohol cooks off taking the water with it is a plus.

Another thing I learned by accident was backing out the main low point drain plug and let out a few oz of UTF after working it a few hours can yield some mostly clear water. I have seen this be the case a couple hours after doing a full drain and filter change. The only thing I can think is the water that forms in the cylinders keeps trying to get back to the low point slump. Alcohol can reach that trapped water.

Our JD 310B BH holds 20+ gallon of UTF and expect it would take 80 gallons to get that last drop from the system. Alcohol put into warm UTF will not hurt the film quality much but I would not work it hard with a large amount of alcohol in it but do something like have my son move every cylinder full stroke 10 times and that includes the stabilizers and steering max which is easy when the front tires are off the ground.

With that being said most all machines have some water in the mix.

 

[Soundguy]

yep. I wouldn't put a huge amount of alcohol it. remember. water that comes into contact will be solvated. a pint every 5g may be plenty. and pretty diluted ( safely ) too.

 

[Crashcup]

Follow up to my earlier questions. I did go ahead and add ATF, 93% isopropyl alcohol, and kerosene, then worked the hydraulics as hard as I could to warm it up. Drained, refilled with new fluid.

It's been several weeks now and the oil still looks very clean. I do believe I finally got the majority of the water out!

 

[Soundguy]

sounds great.

as a preventative you can add a can of transtune seafoam to the mix.. it will help evacuate any incedental water getting in.. or.. just keep running it up to temps each time you use it to flash it off.