RV Generator Parts and Maintenance

When reliability counts, insist on the real thing. From filters to tune-up kits, Genuine Cummins Onan Green Label Parts are made to exact product specifications to maximize the power output and life of your Cummins Onan RV generator.

Genuine Cummins Onan Green Label Parts are available from all certified Cummins Onan RV service and parts dealers.

Maintenance parts can also be ordered online on  cumminsonanstore.com in the United States and the shopcummins.ca website in Canada.

Cummins Onan parts differ from "will-fit" parts

Don't settle for aftermarket or "will-fit" parts. Genuine Cummins Onan parts offer the durability and performance you have come to expect from Cummins Onan. They're the original. The following include some of the parts you'll become accustomed to checking and changing as part of your maintenance routine, as well as the reasons for choosing Cummins Onan parts.

Air Filters

Genuine Cummins Onan air filters are designed with a special foam pre-cleaner, for use specifically in RV generators. Other manufacturers' air filters may contain a lighter-density filter paper and the sealing surfaces may get hard and crack over time, allowing dirty air into the engine intake system. Over time it takes about a thimbleful of dirt to wear out piston rings and cylinders. (Replacement filters for some older models may not include the pre-cleaner.)

Spark Plugs

Genuine Cummins Onan spark plugs come gapped correctly from the factory for your RV generator engine. Spark plugs purchased from other sources come gapped for automotive engines, which are gapped much larger. When regapping, the ground strap must be bent and it may not cover the entire electrode which will reduce spark plug life.

Oil Filters

Cummins Onan RV oil filters feature valves that allow oil to bypass the oil filter during cold starts, or if the filter becomes plugged. Other manufacturers' oil filters often do not have bypass valves. As these "will-fit" filters trap debris, oil pressure starvation can occur, leading to high oil pressures, failed gaskets and even engine damage. Other "will-fit" oil filters do contain bypass valves but they do not determine at what PSI the valve opens. If the setting is too high, the filter's paper element can be damaged during a cold start rendering it useless, or cause oil starvation to the engine.

Customers have comments that the replacement oil filter (part #122-0833) they purchased for their Cummins Onan Quiet Diesels appears to be the wrong size. We hear this a lot! Filter #122-0833 has replaced filter #185-5801 and filter #185-5409. Despite the difference in outward appearance, it will fit your set and the oil ring will provide a proper seal.

OnaMax Oil Update

Available Q2 of 2020. Cummins will offer the all new SAE10W-30 OnaMax™ oil for Onan RV gasoline and liquefied petroleum (LP) generators. The new oil weight offers the same great benefits you find with our SAE15W-40 product.

  • Identical engine oil blend used in RV generator production.
  • Protects against wear in air- or water-cooled engines.
  • Formulated to give protection against oxidation and increased oil viscosity to help reduce engine wear and oil consumption.
  • Provides excellent protection in water cooled engines where high speeds or longer drain intervals may be experienced.

Learn More About OnaMax Oil

The Cummins Onan nationwide network of distributors and dealers can help you with parts and service to keep your Cummins Onan RV generator set in peak condition. To find the location nearest you, call toll-free 1-800-888-6626 or use our Dealer Locator.

RV Manuals

Looking for RV generator manuals? Some of our most popular operators and installation manuals are now available for direct download.

View RV Generator Manuals

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