Cummins/Onan NTA855 — Vibration Isolators Installation and Adjustment Procedure
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 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 vibration isolators on genset support structure; shim or grout bases within 0.25 inch (6 mm) elevation of each other on flat, level surface.
- Loosen side snubber lock nuts so top plate is free to move vertically and horizontally.
- Place genset onto isolators, aligning skid mounting with threaded isolator hole.
- Adjust isolators using leveling bolt so set is level; nominal clearance of 0.25 inch (6 mm) or greater desired.
- Adjust leveling bolts until set is level and sufficient clearance remains; lock leveling bolt with lock nut.
- Snubber nuts may remain loose for better isolation.
- Model DFCE only: remove the two controller cabinet shipping screws before operation.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Clearance 0.25 inch (6 mm) or greater
- Isolator base elevations within 0.25 inch (6 mm)
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.