Cummins/Onan — Lowering Under-Floor Mount Generator Set
Maintenance
From a Cummins/Onan operator's manual — check it applies to your exact model before use.
Applies to: Cummins/Onan NHEL
Before you start
- The generator set falling can cause severe personal injury or death and equipment damage. Use a floor jack to control and support the weight of the generator set. Do not attempt to lower the generator set by hand.
- Oil in the engine cylinders can cause engine damage during starting attempts.
Procedure
- Park the recreational vehicle on as level a surface as possible.
- Put the vehicle in park, lock the brakes, and remove the ignition key.
- Disconnect both battery cables, negative (-) cable first; open the generator set access door.
- Separate the exhaust system near the generator set if it is supported by the vehicle under-structure.
- Check the electrical connections and fuel line for sufficient slack when lowering.
- Position a floor jack under the reinforcement ribs of the drip tray.
- Raise the floor jack until it just makes contact, then apply slight upward pressure.
- Remove the bolts from the front and rear (NHE only) support bracket(s) and remove the bracket(s).
- Slowly lower the floor jack, allowing it to roll as the set swings downward.
- Place wood blocks under the drip tray assembly so the floor jack can be removed.
- Perform maintenance or service procedures.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Drain the oil if the set will be left in the down (tilted) position for more than thirty minutes
Full service-parts list: Cummins/Onan NHEL →
Source: Cummins/Onan operator's 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.