Yes Hydraulic fluid can go bad

[cmorningstar01]

I was reminded how important clean fresh hydraulic fluid is when I went to use one of my log splitters , I have 2...a 22 ton Gas powered model and a smaller 120 volt 5 ton electric model, I had replaced the fluids in the Gas 22 ton splitter in the spring but had not used the electric 5 ton splitter for 2-3 years, I pulled it out, and turned it on and it was moving very slowly and eratically, I checked the hydraulic fluid and it was full but it was very cloudy, So I decided to drain all the old fluid and refilled, Took about an hour and afterward the splitter was up and running, moving like a new one.
One thing I noticed when I drained the old fluid out was that besides being cloudy it was also foamy having a lot of bubbles in it..

 

[GreensvilleJay]

yes, anything 'vented' ,if sitting long enough, will have 'problems'...
my first D-14 sat for 25 years in a 'leantoo shed'. oil in diff drained to the bottom, exposed the diff gears, top 1/2 were rusty !!! Same for the PD packs. After refilling and several trips around got everything running again.....

 

[BAP]

I was reminded how important clean fresh hydraulic fluid is when I went to use one of my log splitters , I have 2...a 22 ton Gas powered model and a smaller 120 volt 5 ton electric model, I had replaced the fluids in the Gas 22 ton splitter in the spring but had not used the electric 5 ton splitter for 2-3 years, I pulled it out, and turned it on and it was moving very slowly and eratically, I checked the hydraulic fluid and it was full but it was very cloudy, So I decided to drain all the old fluid and refilled, Took about an hour and afterward the splitter was up and running, moving like a new one.
One thing I noticed when I drained the old fluid out was that besides being cloudy it was also foamy having a lot of bubbles in it..

Hydraulic oil itself doesn’t go bad, it is from getting contaminated and in your case it sounds like you got water in it. Also, it may have been poor quality oil to begin with.

 

[random]

What is "vented"? To me that would suggest that the hydraulic system isn't totally sealed, but I'm not sure how that makes sense.

How would hydraulic fluid get contaminated in a sealed system?

 

[NCL4701]

What is "vented"? To me that would suggest that the hydraulic system isn't totally sealed, but I'm not sure how that makes sense.

How would hydraulic fluid get contaminated in a sealed system?

Condensation. If there’s any air space in the system, and there is in most systems, there’s moisture in the air even if there’s no air flow. Open the system to fill it or top it off when the atmosphere is warm and humid, system gets cold later on in colder temps, and you have liquid water in the system. Doesn’t take much water to contaminate the oil.

 

[D2Cat]

Your log splitter probably has a vent in the fill plug. This allows air in/out as the fluid heats and cools.

 

[cmorningstar01]

Hydraulic oil like regular oil will deteriorate and break down over time,factors like usage and heat can accelerate the deterioration of the fluid/oil, changes in viscosity, increased acidity and yes water/moisture/condensation will contribute to the breakdown.

The log splitter does have a vent, It is a manual vent that is in the closed position during storage and transportation but you open it by turning a wing nut when in operation

 

[SDT]

Condensation. If there’s any air space in the system, and there is in most systems, there’s moisture in the air even if there’s no air flow. Open the system to fill it or top it off when the atmosphere is warm and humid, system gets cold later on in colder temps, and you have liquid water in the system. Doesn’t take much water to contaminate the oil.

Bingo.

As previously said, the oil did not go bad but moisture contaminated it due to condensation.

SDT

 

[cmorningstar01]

OK guys...Hydraulic oil is a petroleum based product and like all petroleum based products it will deteriorate over time thus...going bad...but as I had indicated heat and also moisture caused by condensation accelerate that.

It's science

 

[SDT]

OK guys...Hydraulic oil is a petroleum based product and like all petroleum based products it will deteriorate over time thus...going bad...but as I had indicated heat and also moisture caused by condensation accelerate that.

It's science

Certainly you are not claiming that the hydraulic oil deteriorated in the time that you have owned your log splitter, heat and/or condensation notwithstanding?

Are you?

SDT

 

[cmorningstar01]

I have owned this splitter for over 15 years and have changed the hydraulic oil a few times that I remember over that period of time, I honestly do not remember when the last time I changed it before this last time, So yes I am indicating that the hydraulic fluid deteriorated in the time since I last changed the oil in it and that the deterioration was accelerated by heat,use and condensation in the system as I have indicated.

Everything that has moving parts sheds molecules of those parts as they move caused by friction and if those parts have a fluid bath then those molecules will shed into that fluid

If you took a gallon of oil and placed it in a sealed container with no air or possibility of moisture/condensation getting into that oil then theoretically it would not change but we don't use oil in sealed containers without the possibility of air/moisture/condensation entering so it will eventually breakdown.

This whole conversation of whether oil/hydraulic fluids break down was based upon the premise that they are used in systems where they are exposed to heat/temperature changes/compression,friction and introduction of contaminants both from internal moving parts and moisture and condensation entering from external vents. My little log splitter does not have any type of filter/filtration system to remove contaminants .


This is the first sentence of my original post " I was reminded how important clean fresh hydraulic fluid "

Clean is the first adjective indicating a lack of contamination

 

[Henro]

OK guys...Hydraulic oil is a petroleum based product and like all petroleum based products it will deteriorate over time thus...going bad...but as I had indicated heat and also moisture caused by condensation accelerate that.

It's science

Using your science, I must observe it is pretty amazing that we get any petroleum out of the ground that is usable, and not deteriorated beyond usability. Guess we just got lucky and timed extraction right! LOL

 

[GeoHorn]

Using your science, I must observe it is pretty amazing that we get any petroleum out of the ground that is usable, and not deteriorated beyond usability. Guess we just got lucky and timed extraction right! LOL

I guess you’re being humorous, Henro... Out of the ground is known as “crude oil”.... Do you use that in your equipment? No,.... I didn’t think so.

Cmorningstar01, ... you are correct that hydraulic oil after much use and time becomes contaminated and molecularly-chained hydrocarbons are altered by heat and shearing action. There’s a REASON Kubota and other mfr’s insist in all their maintenance programs that it be filtered AND CHANGED periodically.... goofy opinions so-far expressed notwithstanding.

BTW, what splitter do you have? I have a HF “Predator” that I believed at first had no filtration....but in-fact, later noticed the parts illustration does indeed indicate one on the return line to the pump INSIDE the reservoir where it is unseen. I don’t know how efficient the filter is or if it’s actually considered a user-serviceable item. I guess I’ll have to go re-read my owner’s manual to refresh my memory. Thanks for the reminder. (I would not have bought it for the few logs I split, but it was a ” mgr’s floor demo” model fully assembled but never started and no fluids for only $500. I risked a traffic citation and violated the placards and towed it on the interstate

highway 200+ miles from Houston to my home west of Austin and it followed me at 70 mph just fine. I serviced it with O’Reilly’s AW32 hyd oil and SAE 30 engine oil and gasoline and it’s been great for the last 4 years now. I probably should sell it as I have no actual use for it. What I like most about it is it is “double-action”...the wedge splits both coming-and-going which really speeds things up.

 

[cmorningstar01]

Using your science, I must observe it is pretty amazing that we get any petroleum out of the ground that is usable, and not deteriorated beyond usability. Guess we just got lucky and timed extraction right! LOL

Everything we get out of the ground is processed to make it usable including removing impurities, Just like oil can be recycled to make it reusable.
My science is actual science

 

[cmorningstar01]

BTW, what splitter do you have?

The small splitter is a SpeeCo splitter, It is a 5 ton electric machine, my other splitter is a TSC 22 ton that has an external filter just like a cars engine