Cummins/Onan NTA855 — Vibration Isolators Installation and Adjustment
Installation
For the Cummins/Onan NTA855, from the Cummins/Onan service manual.
Applies to: Cummins/Onan DFAB, Cummins/Onan DFAC, Cummins/Onan DFBF, Cummins/Onan DFCB, Cummins/Onan DFCC, Cummins/Onan DFCE, Cummins/Onan NTA855, Cummins/Onan LTA10 engine, Cummins/Onan NT855 engine, Cummins/Onan NTA855 engine
Before you start
- Remove shipping screws (two) prior to genset operation. Genset operation with shipping screws in place will damage control components.
Procedure
- Place the vibration isolators on the genset support structure; shim or grout so all isolator bases are within 0.25 inch (6 mm) elevation.
- Loosen the side snubber lock nuts so the top plate is free to move; align top plate with base and springs.
- Place the genset onto the isolators, aligning the skid's mounting with the threaded isolator hole.
- Adjust leveling bolts until the set is level with a nominal clearance of 0.25 inch (6 mm) or greater between top plate and base.
- Lock the leveling bolt in place with the lock nut; snubber nuts may remain loose for better isolation.
- Model DFCE only: remove the two controller cabinet shipping screws before genset operation.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 0.25 inch (6 mm) nominal clearance
- Isolator bases within 0.25 inch (6 mm) elevation
Full service-parts list: Cummins/Onan DFBF →, Cummins/Onan DFCC →, Cummins/Onan DFCE →
Source: Cummins/Onan service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.