Run a modern hydraulic fluid of the weight equivalent to the engine oil you are using now. I think that would be around a ISO 100
I don't see any ISO 100 but is this stuff suitable?https://www.tractorsupply.com/tsc/produc...il?cm_vc=-10005
It says the SAE Viscosity is 10W30. If I can find what they call UNiversal Tractor Fluid of that ISO is that good?
Odd thing, the skid steers tank label says use only 10W40, the operators manual says use Dextron ATF. I don't know why they don't agree on that. What was in it when I got it looks and smells like motor oil not ATF. ATF s a lot thinner than motor oil so that one really confused me. Why suggest ATF in the book but label the tank to take 10W40?
Do not turn up the charge pump pressure unless you want reduced performance.
There is no way to turn it up on this thing as far as I see. It just has the book specs of what is the normal range, so I stuck an oil gauge on it as the pressure sensor and buzzer doesn't work, (I put it on like the service manual says to for testing, on the pressure sensor line) the spec says its suppose to go off )the buzzer and the light) under 50PSI. The spec range of the charge pump says between 90-150 PSI so... I watch the gauge. I was under the impression that midway between 90-150 would be optimal but as long as it runs about 110-120 all the time, I guess I won't worry about it. I'm not too proud to admit I have really no idea what that charge pressure is or means. All I know is the book says "between 90-150". LOL
If there is not a low loop problem, the charge pressure is just fine.
I wouldn't know if it did... what are the signs of a low loop problem? As far as I can tell it runs perfectly fine, no struggle digging or lifting or driving. Works like a bear for as old as it is. Let me know what that is and I'll watch for it.
I think you might need an oil with ZDDP in it.
My thinking was this thing is old, oils are different than they were back in the 70s, so what it was getting with 70s era motor oil is probably not what its getting with 21st century motor oil. Thus my questions and confusion.