Proper bearing clearance is critical to elevator performance. Most jacks perform well with 0.020”/0.035” clearance with some exceptions. For example, Schindler F2 head (MPH) has minimal clearance due to the design of the small cross-section of the seal. To measure for proper bearing clearance, a magnetic base and dial indicator are necessary.
Proper Procedure for Measurement:
- Follow all procedures for safely removing packing.
- Remove all packing and wipers.
- Reinstall separate bearings and lantern rings.
- Replace at least two fasteners to head assembly.
- Secure magnetic base to casing or head. Place the tip of the dial indicator at right angles to the jack surface.
- Gently pry jack into and away from the dial indicator. Notate the range of motion.
- Repeat 5 & 6 at right angle to first reading.
- The largest reading is your bearing clearance. Special bearings should be made if the clearance exceeds 0.040” Dimensions above this range shorten the packing life and increase seal-related maintance
Oil-Related Troubleshooting
Resources: Gorman Co., Inc. Oil Analysis Kit