Sierra 47-237842 Oil Filter – Onan Marine Generator
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Sierra 47-237842 Oil Filter – Onan Marine Generator
A direct-fit replacement oil filter for compatible Onan marine generators, built to Sierra’s marine-grade specifications. Designed to maintain proper oil flow and filtration efficiency through the full service interval, this filter protects your generator’s engine from wear-causing contaminants — keeping your onboard power supply running reliably whether you’re at anchor or offshore.
Sierra’s marine oil filters meet or exceed OEM specifications for filtration media quality, bypass valve performance, and thread fit. Note that the Onan generator line includes multiple engine configurations requiring different filters — always verify fitment against your specific Onan generator model number and service manual before ordering.
Key Features
- Direct-fit replacement for compatible Onan marine generators
- Meets or exceeds OEM filtration specifications
- Quality filtration media for effective contaminant removal
- Correct bypass valve rating for marine generator service intervals
Best Use Case
The right choice for boaters and liveaboards performing routine oil changes on their Onan marine generator who want a reliable, marine-rated aftermarket filter. Particularly suited to larger Onan generator models where this filter is the specified fit — confirm your generator model number before ordering, as multiple Sierra Onan filters exist for different engine configurations. A practical option for those who prefer to keep a spare filter on board for extended passages or remote cruising.
Parts Desk Insights
The Onan generator line uses several different oil filters depending on the engine model. If this SKU doesn’t match your generator, also check the Sierra 47-237804 Oil Filter – Onan Marine Generator. For the OEM Onan filter, see the Cummins Onan Genuine Oil Filter – 185-7444. For a WIX aftermarket alternative, see the WIX Oil Filter 51344 – Cummins Onan Generator. If your generator also needs a raw water pump service, see the Sierra 47-233310 Impeller Kit for Onan or the Sierra 47-233300 Impeller Kit for Onan.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.