Skyjack SJ85 AJ Service Manual

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SJ85 AJ229044ADA
Section 4 – Troubleshooting Information Hydraulic System
4.3 Hydraulic System
4.3-1 All Controls Inoperative
1. Broken or defective drive pump shaft or coupling. Check pump shaft and coupling. Replace if
defective.
2. Hydraulic oil level low. Check oil level. Fill to proper level.
4.3-2 All Boom Functions Inoperative
1. System pump P2 out of adjustment or is
defective.
Refer to section 5 for pump set up procedure.
Adjust 3H-V1 and 3H-V2 to spec. Replace if
defective.
2. Stuck or defective relief valve RV1. Set valve to specifications. Check O-rings and
clean valve. Repair or replace valve as required.
3. Open or defective dump/ enable valve 2H-21A. Clean valve. Check O-rings on valve. Check
operation of valve. Repair or replace valve as
required.
4. Stuck or defective LS bleed off valve FR1. Clean valve. Check O-rings on valve. Check
operation of valve. Repair or replace valve as
required.
4.3-3 No Main Boom Up or Down
No Main Boom Up:
1. Stuck or defective differential sensing valve
DSV3.
Clean valve. Check O-rings on valve. Check
operation of valve. Repair or replace valve as
required.
2. Stuck or defective boom up valve 4H-14. Clean valve. Check operation of valve. Repair or
replace valve as required.
3. Stuck or defective valve V6 (stuck open, or leak
to tank port).
Clean valve. Check O-rings on valve. Check
operation of valve. Repair or replace valve as
required.
4. Stuck or defective check valve CV16 (stuck open,
or leak to tank port).
Clean valve. Check O-rings on valve. Check
operation of valve. Repair or replace valve as
required.
5. Stuck or defective check valve CV13. Clean valve. Check O-rings on valve. Check
operation of valve. Repair or replace valve as
required.
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Skyjack SJ85 AJ Specifications

General

Brand	Skyjack
Model	SJ85 AJ
Category	Boom Lifts
Language	English