Cummins/Onan 1B Series / 1B Series Plant — Operating on natural, butane, or propane gas
Operation · fuel system
For the Cummins/Onan 1B Series / 1B Series Plant, from the Cummins/Onan operator's manual.
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Before you start
- Make sure line pressure of the gas as supplied to the regulator on the plant does not exceed Six ounces per square inch.
Procedure
- Make sure line pressure of gas supplied to regulator on plant does not exceed Six ounces per square inch. If pressure exceeds this value, install a primary regulator.
- Turn on supply of natural gas or vapor fuel and start engine. Do not choke engine or fill carburetor with gasoline. Choke plate must be wide open at all times.
- Set spark plug gap at 0.018 inch for most efficient operation on gas fuel.
- Adjust gas adjustment valve at air intake to obtain best operation at maximum load. Turning valve in decreases vapor; turning out increases vapor.
- If engine speed and generator voltage are unusually high, adjust governor spring adjusting nut.
- Make final adjustment of governor and gas adjustment valve after plant reaches normal operating temperature.
Specs & values
- Line pressure must not exceed Six ounces per square inch
- Spark plug gap 0.018 inch
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.