Skid Steer Oil Contamination

[Rgillard]

Hello All,

I have had a problem with the hydraulic oil in my skid steer loader for a while now. I have changed the oil but that was to no avail. The oil returned to its milky white state. Over the past few weeks the machine has been sitting idle and all of a sudden I noticed a puddle of hydraulic oil forming below the machine. On closer inspection the top of the hydraulic tank was covered in a mix of water and oil. So I cleaned the top of the tank and within a few minutes oil started to reappear. It now is obvious that there is a small crack where the filler pipe connects to the oil tank/resevoir. So anytime it rains water is getting into the oil.

So now that I know where the problem is originating from I want to fix this leak and change all the oil in my machine. Does anyone have a procedure for doing this. do I need to remove all piping and purge them.Or could I just drop the oil , put in a temporary rinse oil for a few minutes. Then drop the temporary oil and put more fresh oil into it. I am good mechanically but have never worked on a hydraulic system this complicated so I don't want to take on something which I am not capable of doing. My Uncle in law is a very good mechanic and I may be able to get some help off him.

In terms of fixing the leak, is rewelding the only option (obviously with tank drained and cleaned) or is there any other product which I could use.

Any advise is greatly appreciated..

Thanks

Ronan

 

[20 20]

What type of SS is this? As far as the draining and rinsing goes, use a solution of diesel(or oil) and a couple of pints of rubbing alcohol run it for a very short period and drain. Not sure how bad the crack is but if it is minor you could clean it up, get it down to bare metal, and try JB weld or some type of gas/fuel tank repair glue. There are many different types of glue out there, the ones I use come in a stick form. You have to cut what you need then kneed the two pieces together. It stinks to high heck but can work wonders in most cases. Use latex or neoprene gloves when working with the stuff it is very sticky and hardens quite fast.

 

[Rgillard]

It's an sk714-5 komatsu...it's a very minor crack but enough to do damage....

 

[Ed of all trades]

If all you do is drain the tank you will still have water oil mix in the pump, lines, valves, cylinders and motors. You need to get the oil, water mix out of there too. To get it all out just flushing is going to be hard as the mix sets up and sticks to things. I would pull it down, parts are pricey and water is hard on all of them. I would not trust a flush.

 

[20 20]

If all you do is drain the tank you will still have water oil mix in the pump, lines, valves, cylinders and motors. You need to get the oil, water mix out of there too. To get it all out just flushing is going to be hard as the mix sets up and sticks to things. I would pull it down, parts are pricey and water is hard on all of them. I would not trust a flush.

Taking it apart piece by piece may have to be done but wwwwhhhhaaaattt a job. Not writiing that your incorrect but I'd go with a good flush 1st, maybe even a couple times before tearing everything down. If everything is running/moving proper then a flush might do the trick without a major tear down. Just my opinion but I believe in KISS(keep it simple silly) then if need be move on to more drastic measures.

 

[Ed of all trades]

I guess I am a belt and suspenders man. I would not take the chance of h2o setting in little places in a machine that cost large $$$$ and would go to the trouble. I know it is a lot of work. I once had three bobcats torn down to that extent side by side, when I worked for a dealer.

 

[Rgillard]

I guess I am a belt and suspenders man. I would not take the chance of h2o setting in little places in a machine that cost large $$$$ and would go to the trouble. I know it is a lot of work. I once had three bobcats torn down to that extent side by side, when I worked for a dealer.

Hi Ed,

Thanks for your replies so far...I think you are right in saying the only way to do it is a full tear down..seeing as you have a lot of experience would you be able to give me a more detailed explanation of what to do? If I am going to undertake this I want to be fully prepared.....Is there any special tools...do I need to actually open up the pump to clean it...how do I clean out the wheel motors, hydraulic rams, piping .....

Another option would be to do a flush and then use a filtration cart to remove the rest of the water?i can hire one for about 50 bucks over here

Thanks
Ronan

 

[Ed of all trades]

The problem is I worked on bobcats and a few case skid loaders 15 years ago. We had a few special tools but none that you could not do without, The pump on a bobcat is very senitive to adjustment and dirt. I don't know about your pump but a bobcat pump would be hard to set up with out help. I hate to say it but if you don't know how to set up the pump the filter cart might be a better answer. Hope all goes well, let me know if i can help in any way Ed If you do pull it down to clean it buy a half dozen cans of carb cleaner and use freely.

 

[slimjim1]

Id strongly recommend you follow the advise of 20 20. We least a hangar next to the maintainece hangar at our local small airport for many years. My dad always bought small plane (piston engine) fixer uppers which gave me summer work & a safe place to drag race as a kid. Dad is still here. I did plenty of bent/broken landing gear repair/replacements back in the day for him. The FAA certified mechanics always used alcohol for the many hydraulic systems during service/repairs, as did I. Water can get anywhere at 200 or 300 M.P.H. If your not going to tare it down totally, add 10% of the holding capacity alcohol to your tank after your tank leak is repaired, run it thru the system till your sure it has circulated completely and the hydraulics are warm, then drain it. Do this twice. Change the filters btwn refills and you should have quite clean fluid with only the smallest amt of water still in there. The 1st flush will work some debris loose. The small amt of water & alcohol remaining ought to evaporate out of the tank breather as time and use goes on and maybe 1 more fluid change within a year. (to prevent rust pitting) If you still decide to tare it all down, use cheese cloth and compressed air as paper towels leave a horrible lint mess to clog the filters & passage ways. I hope this is of some help to you, Best wishes Jim

 

[bigdeano]

I had this happen to my tractor with a loader and backhoe, 11 cylinders total. Here's what I would do.

Park your machine with the front wheels elevated so the cylinders can retract all the way when the loader is lowered. Raise the loader all the way and curl the bucket all the way. Shut the machine off and drain the hydraulic reservoir. Lower the bucket by gravity and dump the bucket. Maybe you'll need a lever to help it. Almost all the oil will be out of the cylinders.

Vacuum pumps are routinely used to remove water from refrigeration systems without taking them apart. At a high enough vacuum water boils at room temperature and the vapor is sucked out of the system.

Take the return hose that goes to the tank loose at the valve bank and hook the vacuum pump to the valve bank. Take the suction hose loose at the tank and cap it off.

Tie the handles in one direction and let the pump run for maybe 12 hours, then tie the valves in the other direction for 12 hours. Then leave the valves centered for a few hours to suck the water out of the pump. The last would work if it's an open center system. If it's closed center you'll have to hook the vacuum pump to the line that comes from the hyd pump.

Harbor Freight has inexpensive refrigeration vacuum pumps, don't know if they're any good though. I haven't used the vacuum method, I didn't think of it then. It should work, hydraulic hoses should withstand vacuum without collapsing. Yours are probably double braid and very sturdy. Obviously don't try to put vacuum on the reservoir or it will collapse.