790 Question?

   / 790 Question? #1  

rjp444us

Bronze Member
Joined
Apr 2, 2002
Messages
80
Location
Rocky Hill CT.
Tractor
JD 790 Satoh Beaver
Here is the Question for all 790 owners.
How long will the hydraulics keep the tractor off the ground and not creep!! Mine goes up and almost immediately it is back on the ground.Especially the backhoe?
 
   / 790 Question? #2  
rjp, mine is pretty much the same. I was working it pretty hard (backhoe) this weekend and it was hot, sunny and humid. After a while I was beginning to think something was wrong as it would not stay up through my first bite of dirt. No external leaks at the stabilizers so it must be internal. I'll have to check my manuals for acceptable leakdown rates.

Normally, I set the loader down first then the stabilizers. A couple of times, working close to the trench I set the stabilizers down first. It seems to raise higher and stay up better when I do that for some reason.

Note I said no external leaks on the stabilizers. I do have some weapage on one of the swing cylinders. I've heard these are pretty susceptible due to the location. How are yours holding up?

/forums/images/graemlins/smile.gif
 
   / 790 Question?
  • Thread Starter
#3  
The swing cylinders were both leaking but the dealer changed them. I think that the leak rate is totally unacceptable and I am going to have a word with the dealer...
 
   / 790 Question? #4  
<font color="blue">I think that the leak rate is totally unacceptable and I am going to have a word with the dealer </font>

Let me know what you find out /forums/images/graemlins/smile.gif
 
   / 790 Question? #5  
Richard, here are the drop rates from the "Horicon Hydraulic Attachments Technical Manual" for the #7 backhoe:

Internal valve leakage -
Stabilizer circuit - 0.73 cu. in./min. max
Lift circuit (with relief and check) - 1.34 cu. in./min. max

Lift cylinder drop rate - .57 in./min max from transport position

Stabilizer cylinder drop rate - .34 in./min max from transport

Stabilizer cylinder retract rate - .23 in./min max from working position

Not sure if this helps you or not but at least you'll have some knowledge in talking to your dealer /forums/images/graemlins/smile.gif
 

Tractor & Equipment Auctions

2000 FORD F450 SUPER DUTY SINGLE CAB FLATBED TRUCK (A51406)
2000 FORD F450...
2020 CATERPILLAR 336 EXCAVATOR (A51242)
2020 CATERPILLAR...
2015 Chevrolet Tahoe SUV (A50324)
2015 Chevrolet...
KEWANCE 200 9' GRADER BLADE (A51243)
KEWANCE 200 9'...
2010 Toyota Corolla Sedan (A50324)
2010 Toyota...
Quick Attach Pallet Forks (A47384)
Quick Attach...
 
Top