Water Exhaust Shutter Kit – Fits MerCruiser Stern Drive 3.0L/3.6L/4.2L Diesel (Replaces 807166A3)
Water Exhaust Shutter Kit – Fits MerCruiser Stern Drive 3.0L/3.6L/4.2L Diesel (Replaces 807166A3) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Water Exhaust Shutter Kit – Fits MerCruiser Stern Drive 3.0L/3.6L/4...
Product Details
This aftermarket Water Exhaust Shutter Kit – Fits MerCruiser Stern Drive 3.0L/3.6L/4.2L Diesel (Replaces 807166A3) is designed for select MerCruiser Stern Drive diesel engines, including the 3.0L VM 183, 3.6L VM 219, and 4.2L VM 254 models manufactured between 1994 and 1997. It prevents water from entering the engine through the exhaust system.
It serves as a direct replacement for MerCruiser part 807166A3 and its predecessors (14348, 14348A1, 14348A2). It also interchanges with Sierra 18-2732, GLM 89170, and Mallory 9-42802.
- Fits oval 4" Y-pipes with round pin holes for secure mounting.
- Engineered for diesel-powered marine applications.
- Durable composite housing for corrosion resistance.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Notes |
|---|---|---|
| MerCruiser | 807166A3 | Supersedes 14348, 14348A1, 14348A2 |
| Sierra | 18-2732 | Aftermarket Replacement |
| GLM | 89170 | Aftermarket Replacement |
| Mallory | 9-42802 | Aftermarket Replacement |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | 3.0L VM 183 Inline 5 | 183 | 4-Stroke | 1994–1997 | 807166A3 | For 0D725152 thru 0F999999 |
| MerCruiser | 3.0L Bravo VM 183 Inline 5 | 183 | 4-Stroke | 1994–1997 | 807166A3 | For 0D725152 thru 0F999999 |
| MerCruiser | 3.6L VM 219 Inline 6 | 219 | 4-Stroke | 1994–1997 | 807166A3 | For 0D850128 thru 9999999 |
| MerCruiser | 3.6L Bravo VM 219 Inline 6 | 219 | 4-Stroke | 1994–1997 | 807166A3 | For 0D850128 thru 9999999 |
| MerCruiser | 4.2L/220 IDI VM 254 Inline 6 | 254 | 4-Stroke | 1994–1997 | 807166A3 | For 0D554732 thru 0M999999 |
| MerCruiser | 3.0L VM 183 Inline 5 (Inboard) | 183 | 4-Stroke | 1994–1997 | 807166A3 | For 0D725152 thru 0F999999 |
| MerCruiser | 3.6L VM 219 Inline 6 (Inboard) | 219 | 4-Stroke | 1994–1997 | 807166A3 | For 0D850128 thru 9999999 |
Technical Specs
- Product Type
- Exhaust Water Shutter Kit
- Installation
- Y-pipe with round pin holes
- Fuel Type
- Diesel
- Connection
- Pin mounting
- Housing Material
- Composite
- Housing Color
- Black
- Dimensions
- Approximately 155.7 mm × 59.9 mm (6.13" × 2.36")
- Weight
- 0.234 kg (8.1 oz)
- Fitting Type
- Direct fit
- Warranty
- Varies by manufacturer; typically 1-year limited
- Other Technical Attributes
- Fits oval 4" Y-pipes with round pin holes
What’s in the Box
- 2 x Water Shutter Assembly (Replaces 807166A3)
Installation Notes
- Disconnect the vessel's battery and ensure the engine is cool.
- Gain safe access to the exhaust Y-pipe where the old shutters are located.
- Carefully remove the old shutters by extracting their mounting pins. Note their orientation.
- Clean any debris or residue from the pin holes and shutter seating area in the Y-pipe.
- Insert the new water shutters, ensuring they are oriented correctly to allow exhaust out but prevent water from flowing in.
- Secure the new shutters with their mounting pins. Confirm they move freely and close properly.
- Reconnect the battery, start the engine, and check for proper operation and no exhaust leaks.
Troubleshooting & FAQ
How do I know if my exhaust water shutters need replacing?
Common signs of failure include a rattling sound from the exhaust Y-pipe, engine overheating at idle speeds, or evidence of water ingestion into the engine. A visual inspection may reveal cracked, broken, or missing shutters.
Is this a single shutter or a pair?
This kit includes a pair of two water shutter assemblies, sufficient to service one compatible Y-pipe.
What is the function of a water shutter?
An exhaust water shutter is a one-way valve that allows engine exhaust and cooling water to exit while preventing water from flowing backward into the engine, which can happen during deceleration, reversing, or in rough seas.
Will this fit an oval Y-pipe with square grommets?
No. This kit is specifically designed for oval 4-inch Y-pipes that use round pin holes for mounting the shutters. It is not compatible with systems using square grommets.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.
Safety & Important Info
- Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
Payment & Security
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