Boiling fluid

[ch1ch2]

I was doing some light shredding yesterday. Low RPM 1K TO 2K. Several stops to cut mesquite trees, and push big rocks. After about four hours work, I stopped and heard the hydraulic fluid boiling in the transmission. It continued to boil for about a minute after I stopped.
I checked the level. It was low but on the stick.
Any Ideas why this happened? Anything I need to fix. I plan on changing the fluid. Anything I need do do different?

 

[davesl708]

Running at a low rpm causes the engine and hydraulics to work harder. Hydraulics work best at high rpms. That increases flow and cooling.
There also could be a restriction in the hyd. line. This forces the fluid through a restriction causing more friction which increases temp..

You may have damaged some seals with the high temp. Keep an eye out for leaks.

Check your cooling fan for damage.

 

[ch1ch2]

Thanks. That makes sense about the low RPM. I had assumed low RPM would be better. I understand how I was wrong.
I got in late yesterday and have not had a chance to check anything mechanical. I am planning on doing that before changing the fluid today.

 

[IceStationZebra]

Are you sure you don't have water in the oil? ISZ

 

[Tx Jim]

I'll bet tractor has an oil cooler. Check to see if it needs cleaning.

 

[Leejohn]

might of had a valve closed and oil was going thru the relief valve all that time.

 

[ch1ch2]

OK thanks for all the input.
Just got back in town.

I changed the fluid. 5 gallons came out of a 9 gallon system. 6 gallons went back in to top it off. I will change it again "soon". The fluid had not been changed in 5 years with only 26 hours on it. The fluid looks contaminated. Strains of two or three colors. Brown and gray and milk.

Radiator is full. No problem there. There was probably condensation contamination over five years. Some leakage from the FEL but I would not think enough to be a gallon low. Maybe so over the years.
I will check the oil cooler.
No relief valve noise. How else might I check?
The alternator was loose. Maybe the fan was slipping also contributing to the cooling problem,but the engine was not running hot.

 

[davesl708]

OK thanks for all the input.
Just got back in town.

I changed the fluid. 5 gallons came out of a 9 gallon system. 6 gallons went back in to top it off. I will change it again "soon". The fluid had not been changed in 5 years with only 26 hours on it. The fluid looks contaminated. Strains of two or three colors. Brown and gray and milk.

Radiator is full. No problem there. There was probably condensation contamination over five years. Some leakage from the FEL but I would not think enough to be a gallon low. Maybe so over the years.
I will check the oil cooler.
No relief valve noise. How else might I check?
The alternator was loose. Maybe the fan was slipping also contributing to the cooling problem,but the engine was not running hot.

Did you use the old oil? Not sure what you meant by 5 gal. came out and 6 went in for a 9 gal. system.
Also, with the oil looking brown, gray and milky I would guess condensation was forming inside. Low fluid level would cause high temp too.

 

[ch1ch2]

That's funny.
No disrespect intended. I guess there might be someone who would reuse old oil.
You put a smile on my face.
The measurement of oil is indicative of how much did not drain out. Or, how much contaminated oil remained in the system. 1/3 of system capacity did not drain. That does not seem like a good thing. I do not think that is as designed.
The filter was fairly new with not many hours. I did not change it. I will change it with the next oil change. Base on the hours vs time; I guess it will be 5 hours or no more than 1 year which ever comes first. This is one of three tractor and it rarely gets used. At close to $200 to change all the oils and filters, it gets to be very expensive to justify at only 5 hours a year. It is still cheaper and more convenient than renting.

 

[davesl708]

ch1ch2.

There may be a second drain plug to get to the remaining oil. If running only a few hours per year condensation may be an ongoing problem.