Skyjack SJ61T Service Manual

Page 140 December 2007
Telescopic Boom Series
Models SJ61T & SJ66T
194312
Section 4 - Troubleshooting InformationService and Maintenance
5. Stuck or defective counterbalance valve CB3.
- Clean valve. Check O-rings on valve. Repair or replace valve as required.
6. Defective lift cylinder C1.
- Check seals on cylinder. Replace as necessary. Replace cylinder if defective.
4.2-4 No Main Boom Down
1. Stuck or defective differential sensing valve DSV2.
- Clean valve. Check O-rings on valve. Check operation of valve. Repair or replace valve as
required.
2. Stuck or defective lift down valve 4H-13.
- Clean valve. Check operation of valve. Repair or replace valve as required.
3. Stuck or defective shuttle valve SV2.
- Clean valve. Check O-rings on valve. Check operation of valve. Repair or replace valve as
required.
4. Stuck or defective check valve CV5.
- Clean valve. Check O-rings on valve. Check operation of valve. Repair or replace valve as
required.
5. Stuck or defective counterbalance valve CB3.
- Clean valve. Check O-rings on valve. Repair or replace valve as required.
6. Defective lift cylinder C1.
- Check seals on cylinder. Replace as necessary. Replace cylinder if defective.
4.2-5 No Turret Rotate Left
1. Stuck or defective differential sensing valve DSV1.
- Clean valve. Check O-rings on valve. Check operation of valve. Repair or replace valve as
required.
2. Stuck or defective rotate left valve 4H-32.
- Clean valve. Check operation of valve. Repair or replace valve as required.
3. Stuck or defective shuttle valve SV1.
- Clean valve. Check O-rings on valve. Check operation of valve. Repair or replace valve as
required.
4. Stuck or defective check valve CV4.
- Clean valve. Check O-rings on valve. Check operation of valve. Repair or replace valve as
required.
5. Stuck or defective relief valve RV2.
- Set valve to specications. Check O-rings and clean valve. Repair or replace valve as required.
6. Stuck or defective shuttle valve SV7.
- Clean valve. Check O-rings on valve. Check operation of valve. Repair or replace valve as
required.
7. Stuck or defective counterbalance valve CB2.
- Clean valve. Check O-rings on valve. Repair or replace valve as required.
8. Turret rotate brake BR1 not releasing.
- Inspect brake for worn seals or broken components. Repair and replace as necessary.
9. Worn or defective swing drive motor M2.
- Check motor. Repair or replace if defective.
4.2-6 No Turret Rotate Right
1. 1. Stuck or defective differential sensing valve DSV1.
- Clean valve. Check O-rings on valve. Check operation of valve. Repair or replace valve as
required.
2. Stuck or defective rotate right valve 4H-33.
- Clean valve. Check operation of valve. Repair or replace valve as required.
3. Stuck or defective shuttle valve SV1.

Skyjack SJ61T Specifications

General

Brand	Skyjack
Model	SJ61T
Category	Lifting Systems
Language	English