Skyjack SJ61T Service Manual

Page 144 December 2007
Telescopic Boom Series
Models SJ61T & SJ66T
194312
Section 4 - Troubleshooting InformationService and Maintenance
- Set valve to specications. Check O-rings and clean valve. Repair or replace valve as required.
6. Stuck or defective counterbalance valve CB7.
- Clean valve. Check O-rings on valve. Repair or replace valve as required.
7. Plugged orice OR2.
- Check orice. Clean if plugged or replace if defective.
8. Defective leveling cylinder C3 or slave cylinder C4.
- Check seals on cylinder. Replace as necessary. Replace cylinder if defective.
4.2-15 Brake will not Release
1. Stuck or defective shuttle valve SV5.
- Clean valve. Check O-rings on valve. Check operation of valve. Repair or replace valve as
required.
2. Defective or misadjusted pressure reducing valve PR1.
- Set valve to specications. Check O-rings and clean valve. Repair or replace valve as required.
3. Stuck or defective brake valve 3H-26.
- Clean valve. Check O-rings on valve. Check operation of valve. Repair or replace valve as
required.
4. Stuck or defective shuttle valve SV6.
- Clean valve. Check O-rings on valve. Check operation of valve. Repair or replace valve as
required.
5. Defective or misadjusted relief valve RV5.
- Set valve to specications. Check O-rings and clean valve. Repair or replace valve as required.
6. Stuck or defective brake release override valve V1.
- Clean valve. Check O-rings on valve. Repair or replace valve as required.
7. Bypassing or defective brake hand pump V3.
- Clean valve. Check O-rings on valve. Repair or replace valve as required.
8. Bypassing or defective brake cylinder BR1.
- Check seals on cylinder. Replace as necessary. Replace cylinder if defective.
4.2-16 Brake will not Engage
1. Brake return spring or defective cylinder.
- Check cylinder. Repair or replace as necessary.
2. Brake valve 3H-26 stuck in shifted position.
- Check valve. Replace if defective.
3. Brake in axle out of adjustment.
- See section 5 for brake adjustment procedure.
4.2-17 No Drive Forward or Reverse
1. Brake not releasing.
- See “brake will not release" in this section.
2. Defective or misadjusted charge pump relief valve RV8.
- Set valve to specications. Check O-rings and clean valve. Repair or replace valve as required.
3. Worn charge pump P1A.
- Check pump. Replace if defective.
4. Defective pump displacement control 4H-15 and 4H-16.
- Check control. Replace if defective.
5. Open bypass valve V6.
- Close bypass valve.
6. Worn or defective drive pump P1.
- Check pump. Replace if defective.
7. Worn or defective drive motor M1.

Skyjack SJ61T Specifications

General

Brand	Skyjack
Model	SJ61T
Category	Lifting Systems
Language	English