Cummins/Onan — Compartment Acoustical Lining
Installation · compartment acoustical treatment
From a Cummins/Onan service manual covering: 3.0 AJ, 4.0 BFA, 5.0 BGA, 6.5 NH, T-012. Check it applies to your exact model before use.
Applies to: Cummins/Onan 4.0 BFA
Before you start
- Insulation must not reduce minimum clearances required to meet ANSI 198.1 and CSA #946 temperature rise requirements for recreational vehicles.
Procedure
- Ensure all joints and corners of compartment are vapor tight to coach interior before lining.
- Cover sound reflective surfaces (back, top, sides, not base) with fiberglass or other noncombustible acoustical material.
- Use acoustical material no less than one inch thick and approximately two pounds per square foot in density.
- Use noncombustible adhesive; test acoustical material and adhesive for heat effects before using.
- A combination of materials, such as lead or viscoelastic material plus acoustical material, can reduce noise even more.
- To prevent line-of-sight noise, add a sound panel (baffle) behind louvered air inlet, spaced to allow minimum free air inlet.
Specs & values
- Acoustical material no less than one inch thick
- Approximately two pounds per square foot density
Full service-parts list: Cummins/Onan 4.0 BFA →
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.