Sierra Oil Drain Kit – 1/2"-20 Thread, 42" Length (47-7891)
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
The Sierra 47-7891 Oil Drain Kit is a 42-inch flexible drain hose kit designed to simplify oil changes on marine engines. It threads directly into the engine's oil drain port, allowing you to drain oil cleanly without removing the drain plug — reducing mess and making routine oil changes faster and easier in tight engine compartments.
Key Features
- 1/2"-20 thread fitting — connects directly to compatible engine oil drain ports
- 42" total length — reaches from engine to oil collection container with ease
- Simplifies oil changes in confined engine compartments
- Eliminates the need to remove the drain plug for routine oil changes
- SKU: 47-7891
Best Use Case
Ideal for inboard and sterndrive engines where access to the oil drain plug is restricted by the engine compartment layout. The 42" hose gives you enough reach to drain directly into a collection jug or oil change pump without contorting around the engine. A worthwhile addition to any onboard maintenance kit for boats that are serviced at the dock or on the trailer.
Parts Desk Insights
Confirm your engine's oil drain port uses 1/2"-20 thread before ordering — thread pitch varies by engine manufacturer and model. This kit is designed for gravity-drain oil changes; if your engine compartment doesn't allow gravity drainage, an oil extractor pump may be a better solution. For oil filters to complete your oil change service, see the Sierra 47-0035 Diesel Oil Filter and the Sierra 47-237800 Oil Filter for Westerbeke Engines.
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.