Cummins/Onan — Check And Adjust Belt Tension
Maintenance · Belts
From a Cummins/Onan service manual covering: GNH-250, GNH-XI0, GNHC4, GNVH450, GV12, GV12 series, GV12-525. Check it applies to your exact model before use.
Applies to: Cummins/Onan GV12
Before you start
- Do not pry belts on with a tool; do not roll tight belts over pulleys.
Procedure
- Tighten belts until 90 to 110 pounds on ST-968 Belt Tension Gauge.
- If gauge unavailable, use finger pressure to deflect belt per Table 3-3.
- Replace pairs of belts in complete sets.
- Pulley misalignment must not exceed 1/15 inch per foot between pulley centers.
- Do not allow belts to bottom in pulley grooves or protrude over 3/32 inch above groove.
- Re-tension new belts after running one hour or more.
Tools required
- ST-968 Belt Tension Gauge Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 90 to 110 pounds
Full service-parts list: Cummins/Onan GV12 →
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.