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Mid-East Nebraska | CCU CODES 061 062 063 / Hitch And SCVS Stop / Reservoir Low
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At start up hydraulic light, level light, and "stop" light are on with diagnostic code CCU 061.
During operation a level low and "warning" light displayed with diagnostic code CCU 062 or during operation level low and "stop" light displayed with diagnostic code CCU 063.
Tractor has not been operated for extended periods of time. It can be normal for clean oil reservoir to drain down through charge pump.
Causes for CCU 062 and 063:
Power beyond or SCV return hose incorrectly routed to sump port instead of motor return port.
Charge pump pick up screen is restricted with foreign material. Check for debris in rear differential housing.
Draining clean oil reservoir when using large single acting cylinders on dump wagons and sugar cane carts.
Clean oil reservoir level switch failed.
Low flow from charge pump.
Excessive leakage through secondary hydraulic pump case drain.
Hydraulic leak in internal pressure passage between secondary hydraulic pump and SCV stack valve.
Clean oil reservoir has drained down through not normal leak path as follows:
Porosity through differential case or through differential pinion shaft quill.
Seepage at differential case to differential shaft quill AROUND CAPSCREWS OR O-RING.
Seepage at differential to clean oil reservoir housing. If sealant was not applied correctly between housings.
When tractor is started, clean oil reservoir should refill and turn off warning lights within two minutes at low idle.
Solutions for diagnostic codes CCU 062 and CCU 063:
Add oil to correct level on site glass. Refer to OM section 95.
Make sure motor return lines are connected to power beyond motor return port or SCV return port, not to sump/ tank port. Case drain lines should be connected to sump/tank port not motor return.
Clean sump screen.
Perform CCU test procedure No.7, clean oil reservoir level switch test, in section 240-15 in TM1576 and inspect wiring to switch.
Perform charge pump flow check in section 270-10 in TM1576.
To perform secondary hydraulic pump case drain leak check.
Start tractor and heat hydraulic oil 80 C per technical manual procedures. It is necessary to heat oil to 80 C in order to simulate field conditions and leakage rate is greater at high oil temperatures.
Stop tractor and disconnect the secondary hydraulic pump case drain line from differential case. Place disconnected line into bucket.
Start tractor, run tractor at 2000 RPM, and activate SCV. (Run test without jumper hose installed in SCV). This will cause secondary hydraulic pump to go to high standy pressure.
Note: Perform same test as in step 3 but do not activate SCV. Leakage from secondary case drain should be within specifications stated in step 4.
For both tests in Step 3 secondary hydraulic pump case drain should not leak more than 2GPM for 30GPM pump (45CCM) and 3GPM for 38GPM pump (57CCM).
Note: If leakage from case drain line on 38GPM pump (57ccm) is 3GPM or more inspect bias piston inside of pump for scoring grooving or visible wear. If bias piston is damaged replace with RE71653 bias piston kit to correct excessive leakage.
Perform internal hydraulic pressure passage leak check between secondary hydraulic pump and SCV stack valve. (Perform secondary hydraulic pump case drain leak check before performing internal hydraulic pressure passage leak check between secondary hydraulic pump and SCV stack valve).
Start tractor and heat oil 38 C.
Remove hydraulic oil filler cap. Activate SCV sending secondary hydraulic pump to high stand by. (Run test without jumper hose installed in SCV).
Listen for oil entering differential case and observe hydraulic oil level site glass to see if oil level is increasing. Possible leak paths in this situation are failed internal pressure passage or failed o-rings between differential case and hitch frame.
If there is no leakage evident between hitch frame and differential case. Perform SCV and hitch leak check in section 270-10 in technical manual.
Finding not normal leak paths from the clean oil reservoir will require disassembly of pump drive housing and differential case. (Enter a DTAC case before disassembly of the pump drive housing and differential case).
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8410 hyd troubles still
