Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 10 - Jul 15
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
Water Distribution Housing – Fits Mercury MerCruiser 4.3L–6.2L MPI Engines (Replaces 863802T2)Water Distribution Housing for Mercury MerCruiser 4. 3L6. 2L MPI Engines This water distribution housing is engineered for a wide range of Mercury MerCruiser MPI engines, from 4. 3L to 6. 2L models (1998present). It serves as a direct, reliable replacement for original equipment, ensuring proper coolant flow in air actuated, closed cooling systems. This component is a direct replacement for Mercury OEM part numbers: 863802T2, 863444T2, 863631T1, and
Water Distribution Housing for Mercury MerCruiser 4.3L–6.2L MPI Engines
This water distribution housing is engineered for a wide range of Mercury MerCruiser MPI engines, from 4.3L to 6.2L models (1998–present). It serves as a direct, reliable replacement for original equipment, ensuring proper coolant flow in air-actuated, closed cooling systems.
This component is a direct replacement for Mercury OEM part numbers: 863802T2, 863444T2, 863631T1, and 863444T1.
- Installation Type: Direct replacement for the OEM part.
- Connection: Designed for air-actuated systems with standard hose fittings.
- Material: Constructed from a durable aluminum alloy with high-grade plastic components.
Part Number Cross-Reference
Use this table to confirm equivalent part numbers across OEM and aftermarket brands.
| Brand | Part Number | Superseded By |
|---|---|---|
| Mercury | 863802T2 | |
| Mercury | 863444T2 | 863802T2 |
| Mercury | 863631T1 | 863802T2 |
| Mercury | 863444T1 | 863802T2 |
Compatible Engine Models
Confirm your engine model/year in the table below. For Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.
Mercury MerCruiser 4.3L MPI
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | 4.3L MPI Alpha/Bravo | 190-220 | 4-Stroke | 1998–present | 863802T2 | Serial ranges: 0M300000–0M614999, 0M615000–0W309999, 0W310000–0W649999, 0W650000–0W658582, 0W658583–0W658583, 0W658584–1A030367, 1A030368–1A030369, 1A030370–1A063239, 1A063240 & Up |
| Mercury | 4.3L MPI Alpha/Bravo EC | 190-220 | 4-Stroke | 2005–present | 863802T2 | Serial range: 1A637496 & Up |
Mercury MerCruiser 4.5L MPI
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | 4.5L MPI 200 Alpha/Bravo | 200 | 4-Stroke | 2010–present | 863802T2 | Serial range: 2A441953 & Up |
| Mercury | 4.5L MPI 200 Alpha/Bravo EC | 200 | 4-Stroke | 2010–present | 863802T2 | Serial range: 2A441953 & Up |
| Mercury | 4.5L MPI 250 Alpha/Bravo | 250 | 4-Stroke | 2010–present | 863802T2 | Serial range: 2A441953 & Up |
| Mercury | 4.5L MPI 250 Alpha/Bravo EC | 250 | 4-Stroke | 2010–present | 863802T2 | Serial range: 2A441953 & Up |
Mercury MerCruiser 5.0L MPI / 350 MAG MPI
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | 5.0L MPI Alpha/Bravo | 260 | 4-Stroke | 1998–present | 863802T2 | Multiple serial ranges from 0M300000 through current production |
| Mercury | 5.0L MPI Alpha/Bravo EC | 260 | 4-Stroke | 2000–present | 863802T2 | Serial ranges: 1A300000–1A611927, 1A611928–1A623184, 1A623185 & Up |
| Mercury | 350 MAG MPI Alpha/Bravo | 300 | 4-Stroke | 1998–present | 863802T2 | Multiple configurations and serial ranges |
| Mercury | 350 MAG MPI Alpha/Bravo EC | 300 | 4-Stroke | 2000–present | 863802T2 | Serial ranges: 1A300000–1A611927, 1A611928–1A623184, 1A623185 & Up |
| Mercury | 350 MAG MPI Horizon Alpha/Bravo & MIE | 300 | 4-Stroke | 1998–present | 863802T2 | Multiple configurations and serial ranges |
Mercury MerCruiser 377 MAG MPI / 5.7L MPI / 6.2L MPI
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | 377 MAG MPI Bravo | 350 | 4-Stroke | 2000–present | 863802T2 | Standard and EC configurations. Serial ranges from 1A300000 & up. |
| Mercury | 5.7L MPI MIE | 350 | 4-Stroke | 2010–present | 863802T2 | Horizon, standard, and EC configurations. Serial ranges from 1A090000 & up. |
| Mercury | 6.2L MPI MIE | 350-380 | 4-Stroke | 2010–present | 863802T2 | Horizon, standard, and EC configurations. Serial ranges from 1A090000 & up. |
| Mercury | MX 6.2L MPI (Bravo & MIE) | 350-380 | 4-Stroke | 1999-2010 | 863802T2 | Horizon MIE and Bravo configurations. Serial ranges from 0M310000 through 1A089999. |
Technical Specifications
| Product Type | Water Distribution Housing Assembly |
| Installation | Direct replacement for OEM part |
| Connection | Air actuated with hose fittings |
| Fitting Type | Air actuated fittings with manual drain capability |
| Housing Material | Aluminum alloy with plastic components |
| Housing Color | Silver/Gray (natural aluminum finish) |
| Dimensions | 8.60"" L × 7.10"" W × 7.70"" H (218.4 × 180.3 × 195.6 mm) |
| Weight | 1.20 lbs (0.54 kg) |
| Warranty | Standard Mercury Marine warranty |
| Other Attributes | Closed cooling system compatible, features white and orange air fittings for easy identification |
Package Contents
- 1 x Water Distribution Housing Assembly (Replaces OEM Part 863802T2)
Explosion Diagram
Installation Guide
- Safety First: Disconnect the boat's battery before beginning work.
- Drain Coolant: Fully drain the engine's closed cooling system to prevent spills.
- Disconnect Hoses: Carefully label and disconnect all hoses attached to the existing water distribution housing.
- Remove Old Housing: Unbolt and remove the old housing assembly. Note the position of any brackets or fittings.
- Clean Surface: Thoroughly clean the engine mounting surface to ensure a perfect seal.
- Install New Housing: Mount the new housing assembly and tighten the bolts to the manufacturer's specified torque.
- Reconnect Hoses: Securely reattach all cooling hoses to their correct fittings on the new housing.
- Refill System: Refill the cooling system with the appropriate coolant mixture.
- Final Checks: Reconnect the battery. Start the engine and carefully check for any leaks around the housing and hose connections.
Troubleshooting & FAQ
How do I confirm this fits my engine?
This housing fits a wide range of MerCruiser MPI engines from 1998 to present, including 4.3L, 5.0L, 5.7L, 6.2L, 350 MAG, and 377 MAG models. The most reliable method is to match your engine's model and serial number to the ranges listed in the ""Compatible Engine Models"" table above.
What is the difference between air-actuated and manual draining?
This housing is designed for modern air-actuated draining systems, which use air pressure to clear water for winterization. It also includes manual drain plugs, providing a reliable and flexible backup for maintenance or in case the air system is not used.
What are the signs that my current water distribution housing is failing?
Common signs of failure include visible coolant leaks from the housing body or fittings, engine overheating alarms, steam from the engine compartment, or noticeable cracks and corrosion on the unit itself.
OEM vs. Aftermarket?
This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.
How fast do you ship and how much does it cost?
We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.
What is your warranty and return policy?
This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.
Important Notes
- Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
- This product is an aftermarket replacement part and is not an OEM component.
- Professional installation is recommended to ensure safety and optimal performance.
Why Choose JLM MARINE?
- Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
- Fast Global Shipping: Free delivery worldwide in 5–15 days.
- Direct from Manufacturer: Competitive pricing without compromising quality.
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy