Mercury Cap-Oil Reservoir 865448A01
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You have 30 days to request a return. All sale items are final sale.
Mercury MerCruiser 865448A01 is a genuine OEM oil reservoir cap used on Mercury / MerCruiser trim pump reservoir assemblies. Current Mercury dealer references identify it as Cap Trim Pump Oil Reservoir, note the cap is yellow, and show 865448A01 superseded to current replacement part number 8M0188327.
Key Features
- Genuine Mercury Marine OEM part number 865448A01 / 36-865448A01.
- Current replacement part number is 8M0188327.
- Used as an oil reservoir cap for compatible Mercury / MerCruiser trim pump reservoir systems.
- Cap colour: yellow.
- Current dealer listing shows GTIN / UPC 745061595576.
- Current dealer shipping specs are approximately 0.03 lb, 1.75 in. x 1.75 in. x 0.88 in.
Engine Compatibility
This is not an engine-only part. The strongest supportable fitment is by the trim pump oil reservoir assembly used on compatible Mercury and MerCruiser systems. Current where-used references connect 865448A01 to applications including NXT1 transom trim pump assemblies, Bravo X / Bravo XR / Bravo XZ sterndrive and transom assemblies, 496 MAG, 8.2 MAG / 8.2 MAG HO EC, 575 SCi, 600 SCi, 565 EFI, 540 HP, Scorpion 377 Sterndrive, and related high-performance Mercury / MerCruiser drive and transom applications.
Serial Number Fitment Notice
Verify fitment by exact engine or drive serial number and the correct trim pump / oil reservoir parts diagram before ordering. The key match is the reservoir and pump assembly, because similar trim pump reservoirs may use different cap styles.
When This Part Needs Replacement
Replace this cap when the original is cracked, missing, loose, leaking, or no longer keeps the trim pump reservoir properly sealed. A secure cap helps keep trim pump fluid contained and helps reduce contamination entering the reservoir.
Installation Notes
Install 865448A01 or its current replacement 8M0188327 only after confirming the correct trim pump reservoir application. This is a reservoir cap, so the cap style and reservoir neck should be matched before installation rather than selected by engine model alone.
Alternate/Superseded Part Numbers
Current Mercury dealer references show 8M0188327 as the active replacement for 865448A01 / 36-865448A01.
Parts Desk Insight
With trim pump reservoir caps, the important match is the reservoir style, not just the word “cap.” Checking the trim pump diagram first usually prevents ordering a cap that looks close but will not seal the reservoir correctly.
Shipping: Ships same or next day for fast Canada wide shipping. ⚓
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.