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John Deere – 1023E, 1025R and 1026R – Rockshaft Leakdown Test

Reference

→NOTE:
The following tools may be required for proper diagnosis:
1. BW15073 Ballast Block
2. Digital Thermometer; GT07253 Temperature Measurement Gun; or equivalent
3. Stop Watch or Timer

( 1 ) Test Conditions

Action:
[1] – DO NOT use I-Match attachment on machine during this test.

[2] – Park machine on flat surface for measurement.

[3] – Install ballast box or equivalent weight of 227 kg ±13.6 kg (500 lb. ±30 lb.)
→NOTE:
BW15073 Ballast Box may be used.

[4] – Raise hydraulic oil system to target temperature of 49° C ±3° C (120° F ±5° F). (See
Hydraulic Oil Warm-up Procedure in this Group.)

[5] – Ensure that ballast box has been cycled up and down 10 times to circulate heated oil through system.

Result:
YES: Go to 2.

( 2 ) Open Rate of Drop Test

Action:
→NOTE:
Make sure all SCV spool valves are in neutral.

[1] – Engage park brake, and place machine in neutral range.

[2] – Open rate-of-drop valve completely.

[3] – Run engine at fast idle. Raise hydraulic temperature to 49° C ±3° C (120° F ±5° F).

[4] – Ensure that ballast box has been cycled up and down 10 times before proceeding.

[5] – Final rockshaft position shall be full powered lift height with throttle set to slow idle.
Shut off engine and wait 30 seconds before beginning measurement.

[6] – Measure vertical distance from floor to rockshaft ball joint center at end of right arm (as determined from seat of tractor) and record measurement.

[7] – Time unit for 5 minutes. Measure distance from floor to rockshaft ball joints (at end of
lift arm) and record measurement.

[8] – Time unit for 5 minutes. Measure distance from floor to rockshaft ball joints (at end of
lift arm) and record measurement.

Result:
YES: Return to diagnosis in progress.
NO: Service rockshaft valve.
NO: Repair leaking seal or O-ring.

( 3 ) Closed Rate of Drop Test

Action:
[1] – Run engine at fast idle. Raise hydraulic temperature to 49° C ±3° C (120° F ±5° F).

[2] – Ensure that ballast box has been cycled up and down 10 times before proceeding.

[3] – Close rate of drop valve fully and back off 1/4 turn.

[4] – Raise rockshaft to full height.

[5] – Shut off engine.

[6] – Close rockshaft rate of drop fully, by hand, before proceeding.

[7] – Pull rockshaft control lever forward and retain in forward position with bungee cord or
similar means and wait 30 seconds before beginning measurement.

[8] –
→NOTE:
Initial height measurement should be taken after lever is pulled forward.

Measure vertical distance from floor to rockshaft ball joint center at end of left arm and record measurement.

[9] – Time unit for 5 minutes. Measure distance from floor to rockshaft ball joints (at end of lift arm) and record measurement.

[10] – Time unit for 5 minutes. Measure distance from floor to rockshaft ball joints (at end of lift arm) and record measurement.

Result:
YES: Return to diagnosis in progress.
NO: Service rockshaft valve.
NO: Repair leaking seal or O-ring.