Skyjack SJ4732 - Platform Will Not Drive in Forward or Reverse; Brake(s) will not Release (Pin Brakes)

118
SJ3220, SJ3226, SJ4720, SJ4726, SJ4732223198ABA
Section 4 – Troubleshooting Information Hydraulic System
4.3-6 Platform Will Not Lower
1. Defective Lift valve 3H-14. Check valve. Replace if defective.
2. Defective Holding valves 2H-13-1 and/or 2H-13-2.
(if equipped)
Clean valves. Replace if defective.
3. Machine overloaded and Overload Lights PL-1
and PL-2 on Emergency Stop buttons ashing.
Check machine limits and reduce weight as
required. Refer to electrical troubleshooting.
4.3-7 Platform Drives Slow
1. Free-wheeling valve V2 open or defective. Close valve. Replace if defective.
2. Flow divider/combiner FD1 defective or is
plugged.
Close valve and clean if necessary. Replace if
defective.
3. Defective Speed valves 2H-18A-1 and/or
3H-18A-2.
Check valve. Replace if defective.
4. Defective Counterbalance valve CB1. Check valve. Replace if defective.
5. Drive Motors M1 and/or M2 defective. Check motors. Replace if defective.
4.3-8 Platform Will Not Drive in Forward or Reverse
1. Open Free-Wheeling valve V2. Close Valve. Replace if defective.
2. Brakes are not released. Check brakes. Replace if defective.
3. Forward Drive valve 4H-16 or Reverse Drive valve
4H-15 is defective.
Check Valve. Replace if defective.
4. Flow/Divider/Combiner valve FD1 defective or is
plugged.
Check Valve. Replace if defective.
5. Defective Counterbalance valve CB1. Check valve. Replace if defective.
6. Drive Motors M1 and/or M2 defective.
Check motors. Replace if defective.
4.3-9 Brake(s) will not Release (Pin Brakes)
1. Brake valve 3H-17 is defective. Check valve. Replace if defective.
2. Defective or plugged Brake Orice O6
(SJ3220/26) or Orice O5 (SJ4720/26/32).
Check valve. Replace if defective.
3. Leaking or defective Brake Cylinder. Check cylinder. Replace or repair if defective.