317/320 Skid Steer doesn't drive straight

Complaint:
The wheels on one side of the machine will not come back up to full speed after slowing them down to make a steering adjustment. This occurs most frequently when traveling down hill, but has also happened on level ground.
Problem or Situation:
John Deere has found that this was a typical situation on a 317 and 320 and is caused by the hot oil shuttle (flushing valve) moving to the reverse direction when slowing the wheels and sticking in that position. This allows some of the drive pressure oil to leak past the shuttle, reducing the forward wheel speed until the flushing valve shifts back to the forward direction.Solution:
The former flushing valve used 6-bar springs.  It has been determined that this pressure is too low.  A new 10-bar flushing valve assembly is now available to correct this problem.  The 10-bar flushing valve assemblies were being installed in all production motors as a running change.  Serial number breaks for this change were captured in the appropriate parts catalogs.
The part number for the 10-bar flushing valve assembly is T223651.  This shuttle valve replaces the 6-bar shuttle valve assembly T208293.
THIS IS VERY IMPORTANT:  The flushing valves must be matched side-to-side.  You cannot have a 6-bar flushing valve on one side and a 10-bar valve on the other side.  After the 10-bar shuttle valve is placed in production, all service part drive motors will be equipped with the 10-bar shuttle valve.  You will not be able to purchase a 6-bar shuttle valve motor.  Therefore, if you are replacing a drive motor that was built before the 10-bar shuttle valve was introduced, the shuttle valve in the remaining motor must be replaced with T223651 to ensure that both motors are equipped with 10-bar shuttle valves.
The flushing valve kits will be provided by your dealership but you have to order them.  If Installation Instructions are not included with the kits, use the procedure below to replace the flushing valve.
1.  Remove the plug (151Z0366), both springs (663X6251), spool (151Z0368), and lower guide (151Z0367) from the end plate of the motor. 
NOTE:  Be sure that the lower guide (151Z0367) is removed from the end plate.  Failure to remove the lower guide will prevent the spool from properly seating in the end plate and will cause plug leakage.
2.  Discard all of the parts removed in step 1.
3.  Install the springs (663X6253), plunger (151Z0424), and plug (151Z0422) into the end plate of the motor.  Torque the plug to 30 Nm (22 ft. lbs).
4. Repeat steps 1-3 for the remaining motor (if both motors are being worked).
5. Start the machine and check for leaks.

Courtesy of John Deere DTAC Solutions

Gear Pump Failure 313 and 317 Skid Steers No Hydraulics

The skid steer has experienced a sudden loss of main hydraulics. The boom and bucket will not operate and the park brake will not release. The 313 and 317 skid steers use an Eaton Series 26 gear pump. Pumps built prior to October 2008 had occasional problems with the heat treat process for the gears. If not properly heat treated, one or both gears can crack. Upon cracking, the gear expands outward, seizing to the aluminum pump housing. In many cases the pump shaft snaps off.

Pumps built after October 2008 have gears with an improved heat treat process. To determine the build date of an Eaton hydrostatic drive pump, look at the pump serial number. The pump serial number is interpreted as follows:
YYMMDDRBBXXXX
YY = the first two digits are the year. 08 is 2008, 09 is 2009, etc.
MM = the third and fourth digits are the month. 01 is January, 02 is February, etc.
DD = the fifth and sixth digits are the day of the month
RBB = Assembly plant. For our pumps RBB is Reynosa, Mexico. U is Hutchinson, KS. Since 2007 all skid steer pumps are Reynosa pumps.
The final four digits are the serial number. Serial numbers starting with 1 are first shift, those starting with 2 are second shift.
Thus, a pump with serial number 081015RBB2033 was built October 15, 2008 at Reynosa, MX. It was the 33rd pump built on second shift.


If your machine has experienced a cracked gear pump failure, it is important to repair it properly and economically. Below is the evaluation, repair, and cleanup procedure following a seized pump failure on the 313 and 317 skid steer.

1. Determine whether your pump was built before or after October 2008.
2. Examine the bushings in the front hydrostat housing.
      a. If one or both bushings are damaged, complete hydrostat pump replacement is recommended. The bushings are not field serviceable.
      b. If both bushings are undamaged, replace only the gear pump.
3. Because this failure mode is sudden and immediate, very little debris is generated and sent downstream. John Deere recommends the following cleanup procedure:
a. Remove the line(s) between the gear pump outlet and the control valve inlet. Thoroughly clean the line(s).
b. Remove and flush the attenuator, if installed.
c. Reassemble the machine.
d. Drain the hydraulic reservoir and visually inspect the interior of the reservoir for debris. If debris is found, add 1-2 gallons of diesel fuel to the reservoir and stir it around to loosen the oil and debris. Drain the fuel and use a shop vac to remove the last of the contamination from the reservoir.
e. Refill the reservoir and install a new hydraulic filter. If you have SuperCaddy or equivalent, filter caddy the oil. If you do not have SuperCaddy or equivalent, proceed to steps f through below.
f. Operate the machine for approximately 30 minutes driving forward and reverse and operating the boom and bucket cylinders through their full stroke.
g. Drain the hydraulic oil and change the filter again.
h. Check hydraulic flow and pressure at the auxiliary couplers. If flow and/or pressure are below spec, replace the system relief valve.
i. change the new hydraulic filter after 10 hours of operation.

Courtesy of John Deere DTAC Solutions

4640/4840 No Hydraulics, No Steering, No Brakes

There are some very simple items to check to verify the problem. First was the problem a gradual failure or an instantaneous failure. What that will tell you is whether something is wore out or if something broke. Second, plumb a gauge into the filter relief valve housing. You are checking to see if your Lube/Charge pump is putting anything out. If you see pressure move on to checking pressure at your main hydraulic pump. If pressure is going to the main hydraulic pump but nothing is coming out remove your system pressure relief valve and inspect it for sticking or wear. If the valve is fine plumb a flow meter directly onto the output of the pump to see if the pump is pumping anything. You could a have just a wore out pump. Now if you don't have any pressure at the charge pump pull out the plug on the filter housing a have someone hold a bucket at the hole and start the tractor if nothing comes out check the pickup screen before the pump is condemned. If the screen is clean as was the case on a tractor I recently did, then you have to tear into the rear of the tractor. The charge pump is located in the rear axle. You cannot just order a new pump. You have to order the specific pieces you need. In order to get to the pump you need to remove the rockshaft housing cover which is a lengthy process. The hole job including the making the special tools to lift the cover will take you between 20 and 25 hours to complete. In my case the pump was good but there was a huge hole in the outlet pipe of the pump.

International Hydro-84 after servicing loses all hydraulics!

When servicing any tractor this something to be aware of is air locking. This happens when the oil in the pump gets drained while changing the filters. The pump will then try to push the air through the system with out any help and most of the time that works but occasionally when the pump can't get rid of the air you need to crack a line to let the air out. With the International Hydro-84 you get under the hood where the steering lines are at their highest point. Crack the line and have someone hold the steering wheel in the direction that is forcing the air out of the line. When oil starts to come out consistently tighten it back up and there you go, you now have your hydraulics back.