Skyjack SJ16 - Platform will Not Lower; Pothole Bars will Not Retract; Platform Drives Slow; Platform will Not Drive in Forward

85
SJ12, SJ16
213558ADA
Hydraulic System Troubleshooting Section 4 – Troubleshooting Information
4.3-6 Platform Will Not Lower
1. Defective Holding/Emergency Lowering valve
2H-13.
Check valve. Replace if defective.
2. Lowering orifice O1 plugged or contaminated. Clear debris from Orifice. Replace if defective.
4.3-7 Pothole Bars Will Not Retract
1. Defective or sticking Pothole valve 2H-21. Check valve. Replace if defective.
2. Defective or binding Pothole Cylinder. Check for mechanical binding. Rebuild cylinder
seals. Replace if defective.
4.3-8 Platform Drives Slow
1. Drive motor M1 or M2 defective. Check motors. Replace if defective.
4.3-9 Platform Will Not Drive in Forward
1. Forward drive valve 4H-16A defective or is
sticking.
Clean Valve. Replace if defective.
2. Counterbalance valve CB1 defective or is
plugged.
Clean Valve. Replace if defective.
4.3-10 Platform Will Not Drive in Reverse
1. Reverse drive valve 4H-15A defective or is
sticking.
Clean Valve. Replace if defective.
2. Counterbalance valve CB1 defective or is
plugged.
Clean Valve. Replace if defective
4.3-11 Brake(s) Will Not Release
1. Brake valve 2H-17 defective or is sticking. Clean valve. Replace if defective.
2. Brake Override Valve V1 is defective. Check valve. Replace if defective.
3. Defective Brakes BR1 and/or BR2. Inspect wheel motor assembly. Check if hydraulic
pressure is available at brake hubs.Rebuild/repair
brake hubs if required. Replace if defective.