Skyjack SJ1044 TH - No Aux. Functions; Hard or no Steering; Park Brake will Not Release

125
SJ1044 TH, SJ1044 THS, SJ1056 TH, SJ1056 THS, SJ1256 THS
230790ABA
Hydraulic System Section 4 – Troubleshooting Information
5. Stuck or defective frame level valve V4.
Clean valve. Check operation of valve. Repair or
replace valve as required.
6. LS check valve CV4 blocked or defective
Clean valve. Check operation of valve. Repair or
replace valve as required
7. Stuck or defective frame level counterbalance
valve CB6
Clean valve. Check O-rings on valve. Repair or
replace valve as required.
8. Stuck or defective frame level counterbalance
valve CB7
Clean valve. Check O-rings on valve. Repair or
replace valve as required.
9. Defective frame level cylinder C9
Check seals on cylinder. Replace as necessary.
Replace cylinder if defective
4.3-5 No Aux. functions
1. 4H-233/4H-234 stuck or defective.
Clean valve. Check operation of valve. Repair or
replace valve as required
2. Stuck or defective Auxiliary counterbalance valve
(if equipped)
Clean valve. Check O-rings on valve. Repair or
replace valve as required
3. Defective Auxiliary/Optional cylinder(s).
Check seals on cylinder. Replace as necessary.
Replace cylinder if defective.
4. LS check valve CV13 blocked or defective.
Clean valve. Check operation of valve. Repair or
replace valve as required
4.3-6 Hard or No Steering
1. Stuck or defective EC1 valve
Clean valve. Check operation of valve. Repair or
replace valve as required.
2. Stuck or defective steering motor OSM1.
Check O-rings and clean valve. Repair or replace
valve as required.
3. Defective steer cylinder C1 and/or C2.
Check seals on cylinder. Replace as necessary.
Replace cylinder if defective.
4. LS check valve CV5 blocked or defective.
Clean valve. Check operation of valve. Repair or
replace valve as required
5. Orifice OR1 plugged Remove and inspect, clean or replace as required
6. Relief valve RV2 valve misadjusted or defective Adjust pressure, replace if defective
4.3-7 Park Brake will not Release
1. Stuck or defective park brake valve 3H-26
Clean valve. Check O-rings on valve. Repair or
replace valve as required
2. Bypassing or defective parking brake seals in
axle.
Check seals, replace as necessary. Replace if
defective