Foton: Instal an inline filter on hydrolics

[Bob Rooks]

FWIW, most high-end hydraulic systems will utilize pressure side filtering. It's not an uncommon thing. It's easy for a $5,000 pump to trash a $15,000 valve body, servos, motors, and cylinders. I have seen systems with filters between each component along the flow path (not that it's necessary with these tractors).
On my backhoe I'm running a 25µ 20gpm rated suction side filter @ ~7-8gpm along with a 10µ return line filter.

 

[valley]

By controller valve do you mean the valve that raises the FEL? I'ed like to wait until spring before opening that up. Can you clean it up[ the controller valve] blow it out and reassemble it with it on the FEL. I scrubbed out the hydraulic tank before putting in new oil. I didn't flush out the whole system. When its warmed up it now works great. Does anyone use 15 hydraulic oil? That should be thiner when cold. I have never been in a FEL valve, I guess you would want a repair kit if you opened one. Richard

Just rebuilt the starter what a difference!

 

[greg_g]

If you have no other complaints about the loader activity (other than it's just slow), then there's likely nothing more seriously wrong with the controller valves than plain old dirt. And assuming your loader controls are above sump level, they can be removed for cleaning without much mess.

Yes, ISO15 will work. The smaller the number - the thinner the fluid. Although I've never personally seen any, I understand sub-arctic fluid is available all the way down to ISO5. But if your problem is nothing more than dirt, going thinner won't likely help.

//greg//

 

[valley]

Greg, Is there a screen or screens in the controller valves? You're thinking I might take it apart and clean the valve and put it back together with a kit? Also there are two valves between the pump and the FEL valves. The priority valve, and the valve that next to the operators seat. Richard

 

[valley]

what I've done so far is clean out the sump, extend the suction tube lower in to the sump, fill with fill with 32 hydraulic oil. I've done a number of other things but the above are the only things that reflect on the hydraulics. Now when the oil heats up it works fine. However when cold I have to crank the steering over to full stop to lift the FEL. Once it heats up its good but it takes a good while to heat up.
I don't consider the problem solved. My Michigan loader takes a couple minuts but when its ready she lifts like a champ no working up to it.

 

[greg_g]

Greg, Is there a screen or screens in the controller valves?

Don't know your particular loader, but I doubt it. And as I suggested before - if you have no other FEL problems besides sluggish when cold - no "kit" should be required. Just disassemble/clean/reassemble. Same with the priority/diverter valve. But if the rear lift is working to your satisfaction, I don't believe there's any need to fool with the flow control valve.

when cold I have to crank the steering over to full stop to lift the FEL.

I believe that may be the fault of the priority/diverter valve. Should be able to tell for sure as soon as it's cleaned and reinstalled.

//greg//

 

[greg_g]

I looked at all the hydro systems in the 50 plus airplanes

FWIW, most high-end hydraulic systems will utilize pressure side filtering.

I understand, and I'm not being argumentative here - just trying to sort out the differences in my head. But those are closed systems, right? That is, you don't ordinarily expect any outside contamination to enter - as you would with the open systems (vented sumps) on these Chinese tractors. Since it's commonly the sump where the contamination often enters - wouldn't it be just as important to screen/filter fluidon the way to the pump?

//greg//

 

[Diamondpilot]

Most if not all the airplanes hydro systems were vented to atmosphere just like ours. The jets usually take a tap off the bleed air system that pressurizes the cabin to put head pressure on the reservoir at 15,000' or above or there abouts.

Chris

 

[Bob Rooks]

But those are closed systems, right?
Nope. I think most all systems are vented to atmosphere, albeit some atmospheric vents are more highly filtered than others.

Wouldn't it be just as important to screen/filter fluid on the way to the pump?
Most definitely, and highly recommended.

12345

 

[valley]

Greeting, Well! Guess I'll open up the valve on the loader first. I have never seen an expanded view. Are they spool valves or Orings? Have you had one open?