Recently bought a '73 JD 310,a county owned hoe that looked it's age but was all intact,with 3900 hrs. showing.With a little help from this forum i've re-packed and installed a used swing cyl.that now works as it should. I've also replaced tires,(36)hyd. hoses,fuel lines,air,trans. and hyd. filters,hyd.oil,engine oil and coolant,cleaned and painted ,and freed up shuttle shift linkage.It seems to be running strong with little smoke,but i'm having an issue with the hoe operation.When i'm pulling back with the hoe(like digging a trench)it seems like it's starving for fluid.Fluid level is full with all cyl. extended.
What does it do that seems like it's starving for fluid? make a bad noise, or no noise? Is this when the stick is stalled even though you have the control lever all the way back? one function at a time or a couple at once? Picture of the hydraulic pump also please. even if you borrow it off the net, just want to know what yours looks like. Or a serial number.
The 36 hydraulic lines probably cost more than all 4 tires..And rims..They sure are proud of them lines...
Radial piston pump that uses the transmission pump for charge pressure.
that would be nice, but his only other thread says " restoring a 94 310b" so I'm not holding my breath on either one being what this machine is.
When I originally bought this machine from the second owner ,he represented it as a "94 310b,looking at one of the #ser. no. on this machine,it has one no. with 94 and 310b in it. Not knowing any better I took his word for it,after all he seemed like a straight shooter, like i consider myself to be. I didn't find out the true DNA of this machine until my dealer looked it up and found out the machine was originally purchased by the county in 1973,and is a 310.It seems eratic and slow when pulling up and back at same time.This is with only a third of the travel in the lever,pulling all the way back it it stops and pump gets loud.
Gotcha, so your hydraulic pump looks like the picture? with eight fairly large hex heads around the circumference? obviously you can't see the face with the driveshaft. Is this problem with the machine all warmed up and at full throttle, or close to full speed? "pulling all the way back it stops" is this with the bucket in the air? or sunk in the dirt? Sounds like your charge pressure is low, have you cleaned the suction screen? changed the hydraulic filter? what did they look like, what kind of debris? after that is done, if the problem is the same, then checking the charge pressure at the hydraulic pump inlet would be the next step. What transmission does this have? and does it operate correctly in all gears?
It has 4 speeds with hi and low range,shuttle shift forward and reverse,it all works smoothly.I changed hyd. filter and the filter next to which I assume is trans. filter,it all looked clean,no trash.I'll check suction screen,I will have to go to school on charge pressure,wating on a part, it will be a few days before I can resume,thanks for all the info.
Stinky, The 36 hydraulic lines probably cost more than all 4 tires..And rims..They sure are proud of them lines... https://www.discounthydraulichose.com/ I just replaced 15 hoses, cost with shipping was about $780. Joe H
I ordered my hyd. hoses from "Bailey Hydraulics",I think it was $900.and change with shipping,they're imported but if you can get past that they look good.
When I rehabbed my machine, replaced most of the hoses through a local company that was on the path from home to work..Used Eaton Aeroquip hoses and fittings, pretty reasonable and if you paid cash,the guys making the lines would "cut you a deal" still a pretty expensive deal...The company I now work for has auger trucks that supply feed to farms and are constantly in need of new hoses, we make new hoses in house and I have access to any size hose/fitting a feller could use for any backhoe application and don't need any...Darn the luck....