Loader 790 Hydraulics problem with Steering and FEL

[redmtnex]

Howdy all
I have a 2001 790 with a FEL and backhoe. Just recently the fell and steering stutter, in other words they are not moving smoothly. It's almost like some check valve somewhere is popping in and out. There seems to also be some noise associated with the stuttering. You can feel it in the steering wheel when turning left or right. The fel when lifting. Dropping the FEL is OK. If I lower the rpm the stuttering decreases, barely noticeable when lifting the fel. Any thoughts would be appreciated before I take it to the dealer for the big bucks. Trans oil level is good. Hydraulics do not have the kit installed to increase the pressure. Also I have not had a chance to do a test with the back hoe to see if it is duplicated there.

 

[RoyJackson]

If it's been a while, the first thing I'd do would be change the hydraulic oil and filter. That's about the cheapest thing you can do...

 

[redmtnex]

If it's been a while, the first thing I'd do would be change the hydraulic oil and filter. That's about the cheapest thing you can do...

I probably only have about 15 hours on the new oil and filter. When I pull the dip stik its clean with a slight orange tint on a white rag.

 

[kebo]

Did you clean the suction screen when you last changed the hydraulic fluid? FYI, according to my 790 manual, JD recommends changing the hydraulic fluid every 500 hrs. However, it certainly won't hurt it to change it more often than that.

 

[RoyJackson]

Did this start after you changed the hydraulic fluid/filter? If so, check your filter to ensure it's tight (and not sucking in air). If you did clean the suction screen, make sure everything you loosened is tight.
Also, re-seat your Quick Disconnects on the FEL hydraulic lines (they can loosen).
It

 

[redmtnex]

@ Kebo, The previous owner did the oil change etc. at 336 hours. I was wrong on the total hours since the change as I am now at 384 hours.
@ RoyJackson, this started recently, in the last two hours of operation.

I will take a look at everything today. To get to the suction screen will I need a gasket? And as a note the oil is so clean that it is hard to tell the level on the dip stik unless you have bright light. To me it acts like it is sucking air or the fluid level is really low. I am assuming power steering is the same system as the FEL etc.

 

[kebo]

Been a while since I pulled the suction screen housing off on my tractor, I can't remember if it has a gasket or an o-ring on it. Unfortunately, the operators manual doesn't go into that much detail but I seem to recall that I re-used whichever one it was. No leaks since then. I think you can go to the John Deere website and pull up the exploded view and take a look at it.

 

[redmtnex]

Been a while since I pulled the suction screen housing off on my tractor, I can't remember if it has a gasket or an o-ring on it. Unfortunately, the operators manual doesn't go into that much detail but I seem to recall that I re-used whichever one it was. No leaks since then. I think you can go to the John Deere website and pull up the exploded view and take a look at it.

OK thanks, the breakdown shows an o-ring. The screen is much larger than I imagined.