Water in Fluid

[Tgunn]

Hydraulic rookie here. I just aquired a backhoe that fits my old Kubota. (Tractor L2550, Backhoe L4530 A) It does not run off of the tractor hydraulics but on a pto pump. I hooked it up & it works pretty good. Several leaks but nothing major. Then I noticed that the leaks started looking milky. I drained the oil tank & it was half full of water. How do I proceed to insure I get all water out of all parts of the system?
There is a spin on oil filter that I can't tell if its original or "customized". I'll check with my Kubota dealer to try to get a fit for that.
Please be specific & kind. I am a total rookie at dealing with hydraulics.
Thanks for your help,
tgunn

 

[texasjohn]

Good that the hydraulic systems are independent... so your tractor is not contaminated.

Yes, milky = water in the hydraulic fluid.

I had a similar problem with a dump trailer... milky color as well as a highly clogged up filter.

I would drain all fluid, remove the tank/clean inside it as well as you can. Be sure to replace the filter... depending on how contaminated the system is, you may have to replace/clean it off several times.

It is possible to blow air thru the system for those components that you can get to and disconnect so all fluids are expelled.

That's what I did for my dump trailer.... and I need to replace the fluid again to further remove remaining h2o.

Good luck!

 

[Tgunn]

Thanks! From what I have read searching this forum, I understand that there is no need to bleed anything, that it will do that as I cycle everything? Is that correct?
And, that any water that is now in the lines will be pushed back into the tank, therefore change it as many times as it takes?
Sounds like even I can handle that.
Thanks!
Travis

 

[Tgunn]

As long as I'm asking dumb questions, how is the best way to clean out the tank?
Thanks

 

[kennyd]

The best you can do at this point is to retract all the cylinders, then drain the tank and replace the filter. This may take two or three flushes to get all the water out so you may want to get some cheaper fluid at first. Also check the vented cap well as that's probably the source of the water getting in.

 

[texasjohn]

Kennyd, in my dump trailer, the vented cap lets air enter the tank... and I assume that this is where the moisture enters... when high humidity... then ( I assume) condenses out as water. The pump and tank are in a metal enclosure so that rainwater cannot enter that area (unless lid is left up). Is this condensation the "source of water" you are referring to? If so, how can it be prevented since the tank is supposed to be vented.

In my case, there was a lot of white goop... mayonaise kinda stuff... all over the filter and elsewhere in the system. It's this contamination that sticks in the hoses and elsewhere you are trying to remove. Ummm gets kinda expensive to repeatedly drain multiple gallons of hydraulic fluid... in my area 5 gallons is about $27 for the cheap stuff.

In my case, the tank could be completely removed (unbolted) and when the pump was removed from the tank there was a large opening that I could get my hand into and use rags to completely remove all the gunk clinging to the sides and bottom of the tank.

 

[whodat90]

As said, retract all the cylinders, drain the tank, and refill with cheap hydraulic fluid. Add a couple bottles of HEET or similar gas line antifreeze stuff you'll find in the autoparts section. It's basically pure alcohol, which is both water soluble and petrochemical soluble, so it'll kind of dissolve all the water into the hydraulic fluid. Operate the controls a bit to get all the old stuff out, then retract and drain and refill again. That should get most of it at once.

 

[kennyd]

Kennyd, in my dump trailer, the vented cap lets air enter the tank... and I assume that this is where the moisture enters... when high humidity... then ( I assume) condenses out as water. The pump and tank are in a metal enclosure so that rainwater cannot enter that area (unless lid is left up). Is this condensation the "source of water" you are referring to? If so, how can it be prevented since the tank is supposed to be vented.

I meant to check the cap to make sure that no water can run into the tank-he said that his tank was "half full of water" so I am assuming that this not just a condensation issue.

Ummm gets kinda expensive to repeatedly drain multiple gallons of hydraulic fluid... in my area 5 gallons is about $27 for the cheap stuff.

I understand hydraulic fluid is expensive, but there is no other way to flush the system short of completely disassembling every component.

 

[texasjohn]

KennyD... understand, agreed, thanks!

 

[SkunkWerX]

I understand hydraulic fluid is expensive, but there is no other way to flush the system short of completely disassembling every component.

And, for a moment, let's say you did break down the tank, hoses, and cylinders to individually clean them, in the end, you would still end up doing at least 1 full flush-fill after re-assembling, and probably two flush n fills to ensure you got everything purged.

Walmart is probably the cheapest place.

If you knew the source, I wonder if you could get away with using Once-used hyd-fluid from a clean tractor, for the first Purge , while using the HEET additive? Then follow with another Purge of brand new, and then finally, your fill-up with more new.

Good Luck.

 

[texasjohn]

My plan, exactly, is to use my next tractor fluid drain to replace the fluid in the dump trailer.... the tractor fluid is always almost pristine looking.... will be a good place to reuse it.

 

[Tgunn]

I haven't had a chance to do all of the above yet. I have removed the tank & cleaned it. Not knowing much about this, is there some reason this wouldn't work?: Can I refill with new fluid but not connect the return line. Putting the return line into a 5 gal bucket to catch oil returning to the tank. Therefore not re-contaminating the system. I realize I would have to be careful to not run it out of oil as I worked all the cylinders to expel the old contaminated fluid.
There may be an obvious reason I shouldn't do this but as I look at it, it makes me say hhhmmm. Seems like I could get rid of the bad oil without contaminating the new. Maybe only having to replace the oil once.
Suggestions? Comment? Tell me I'm stupid?

 

[kennyd]

Tgunn, Your idea will work for the most part, but the fluid will come out of that return line very fast and under pressure. YOU MUST BE EXTREMELY CARFULL! High pressure fluid can pierce the skin and cause extreme tissue damage requiring amputation.

 

[Reg]

It takes surprisingly LITTLE water in oil to turn it milky, and only a little more to turn it creamy.
If you don't know the history, it is at least POSSIBLE that accumulated snow could have somehow melted into the tank.
Forget this comment if you are in the sun belt, I'm not.

I would just do a single straight fluid & filter change, then keep doing them at the recommended intervals.

 

[KYErik]

I had the same fluid issue when I bought my used Case 530 hoe. If you plan things properly, you can get most of the milky fluid out the first time by forcing it out of the full end of the cylinders.

The goal is to put the hoe in a position so that gravity will help you push the rest of the contaminated fluid out of the cylinders after you drain the tank.

1. put the machine in the appropriate position (stabilizers down, boom and dipper up and out, bucket extended) and shut it off

2. drain the hydraulic tank and leave the drain plug out

3. one at a time, have a helper hold each control lever so it can "vent" and then manually move each part to force most of the old oil out of the cylinders (the other end of the cylinder will fill with air). This needs to be planned carefully.

You have 5 sets of cylinders- stabilizers, swing, boom, dipper and bucket.

I'd start with the dipper let it- come in halfway (by gravity). Next let the bucket curl (use a come along to force it all teh way in. Manually swing the boom from side to side (it should still be off the ground). Use a come along to fully retract the dipper. Allow each stabilizer to retract and use a come along or farm jack to push it all teh way up to its transport position. Finally, let the boom down until it touched the ground. The only contaminated oil you have now is what is left in the boom cyclinder (unless you dropped it into a deep hole and it pushed everything out) and a little in the hoses.

Be very careful if you choose to do this and definitely have a helper to work the levers. It won't get all of the water out but it may save you one flush- I know it did for me.

 

[sandman2234]

Due to the rust factor, I would get that water out as soon as possible! It can't be good for the system.
David from jax

 

[tom_k]

As said, retract all the cylinders, drain the tank, and refill with cheap hydraulic fluid. Add a couple bottles of HEET or similar gas line antifreeze stuff you'll find in the autoparts section. It's basically pure alcohol, which is both water soluble and petrochemical soluble, so it'll kind of dissolve all the water into the hydraulic fluid. Operate the controls a bit to get all the old stuff out, then retract and drain and refill again. That should get most of it at once.

Have you actually done this? And you never observed any bad effects from the alchohol on rubber components (seals etc) in the hydraulic system?

Are you just adding the Heet to a load of fluid, then draining immediately?
Or do you operate the tractor so the stuff is moving through the system under pressure? In that case, how long do you leave it in?

When I get the time, it'd be interesting to mix up a little Iso-Heet with my NH 134 transmission oil, drop a couple of O-rings in a glass full, and see what happens after a few days. I'm guessing nothing, but would not want to guess with a nearly new tractor.