Hydraulic fluid flush on 555

[rdwyer]

On a 1984 555, can someone share the hydraulic fluid flush procedure? I’ve removed the tank and cleaned the metal screen inside it. I have a filter element coming in a day or two that fits in the canister on the right side of the tractor. But how do I get the fluid out that’s in the lines and cylinders?

 

[AntiqueIron]

I’ve never “flushed” a hydraulic system in the literal sense of the word.

If the reservoir/sump is horrible as far as sludge goes, I’ll use diesel fuel or the like to completely flush it out. Fill it to the max, then drain it. NEVER start the engine while doing this! Be certain you’ve drained it all out too.

Then refill with an inexpensive hydraulic fluid, run the machine around a bit, then change the fluid again. Sometimes you have to do a couple changes to get everything out.

 

[rdwyer]

Ok thanks. I’ve poured about 7 fresh gallons in so far. I still need to replace the filter cartridge which will get done this week. Yesterday I started the game of blowing hydro lines…this one was on the loader. As I work all the controls to get a feeling for what is what, I’m sure I’ll lose some more lines on this old backhoe so the fluid is likely to be replaced one way or another.

A further question… yesterday I crawled under it from the left side and I could see a large white spin on filter situated vertically roughly below the fuel tank. Is this a transmission filter? Mine leaks at a decent clip. I’ll replace it once I figure out what it is and then try to see where it’s leaking. It wasn’t loose.

 

[joecdeere]

I'm guessing we're working on a Ford 555 or 555A TLB since you say it's a 84 model, the hydraulic filter for the loader/backhoe section is the canister mid-way down the right side of the machine laying on its side. The spin-on filter underneath the tractor on the left side just in front of where your feet are is the transmission filter for the torque converter transmission. As far as flushing it, if you drain it with as many of the cylinders in the retracted position, you would get the maximum out. Since you've already done the tank filter, you've done more than 99% of owners ever have. Just let all that will drain from the canister when you take it apart, and I'd call that as good as you're gonna get at home.