Exhaust Flapper with Grommets – Fits MerCruiser Stern Drives 2.5L, 3.0L, 3.7L (Replaces 60930, 18-2727)
This exhaust flapper is designed for MerCruiser Stern Drive applications, including 4-Cylinder 2.5L, 3.0L, and 3.7L engines manufactured between 1982 and 1998, as well as V8 engines equipped with a Jackshaft from 1985 onwards.
It serves as a direct replacement for several OEM and aftermarket part numbers, ensuring compatibility and a proper fit for your engine's exhaust system.
-
Installation Type: Direct Replacement
-
Fuel Compatibility: Gasoline
-
Included Components: Includes one exhaust flapper and two grommets for a complete installation.
Part Number Cross-Reference
Use this table to confirm equivalent part numbers across OEM and aftermarket brands.
| Brand |
Part Number |
| Mercury MerCruiser |
60930 / 25-43809 |
| Sierra |
18-2727 |
| Mallory |
9-42800 |
Compatible Engine Models
Confirm your engine model/year in the table below.
| Brand |
Model |
Rated HP |
Stroke |
Years |
OEM Part No. |
Notes |
| MerCruiser |
4-Cylinder |
2.5L |
4-Stroke |
1982-1998 |
60930 |
|
| MerCruiser |
4-Cylinder |
3.0L |
4-Stroke |
1982-1998 |
60930 |
|
| MerCruiser |
4-Cylinder |
3.7L |
4-Stroke |
1982-1998 |
60930 |
|
| MerCruiser |
V8 with Jackshaft |
Various |
4-Stroke |
1985-Up |
60930 |
|
Technical Specifications
| Specification |
Value |
| Product Type |
Exhaust Flapper Shutter |
| Installation |
Direct Replacement |
| Fuel Type |
Gasoline |
| Housing Material |
Premium Metal and Rubber |
| Dimensions |
79 mm × 94 mm (3.1" × 3.7") [width × length] |
| Other Technical Attributes |
High hardness, durable construction |
Package Contents
-
1 x Exhaust Flapper (60930)
-
2 x Grommets
Installation Guide
-
Safety First: Ensure the engine is completely cool and the battery is disconnected before starting.
-
Locate Flapper: Identify the exhaust flapper's location, typically within the Y-pipe or exhaust outlet housing.
-
Remove Old Components: Carefully remove the old, worn-out exhaust flapper and its grommets. This may require prying.
-
Clean Housing: Thoroughly clean the inside of the housing, removing any carbon buildup, rust, or old rubber fragments.
-
Install New Grommets: Press the two new grommets firmly into their designated holes in the housing.
-
Insert New Flapper: Align the pins on the new exhaust flapper with the holes in the grommets and slide it into place.
-
Verify Movement: Check that the flapper can swing open and closed smoothly without sticking or binding.
-
Final Check: Reconnect the battery, start the engine, and listen for any unusual noises or check for exhaust leaks.
Troubleshooting & FAQ
Q: How do I confirm this exhaust flapper fits my engine?
A: This part fits MerCruiser 4-Cylinder (2.5L, 3.0L, 3.7L) engines from 1982-1998 and V8 models with a jackshaft (1985-Up). To be certain, please verify your OEM part number is 60930, 18-2727, or 9-42800 and check the compatible models table.
Q: What are the symptoms of a bad exhaust flapper?
A: Common signs of a failing flapper include a distinct rattling or clattering noise from the exhaust at idle speeds, water backing up into engine cylinders, or visible cracks and deterioration on the flapper itself upon inspection.
Q: How often should I inspect or replace the exhaust flapper?
A: It is recommended to inspect your exhaust flappers annually during routine maintenance. We suggest replacement every 3-5 years, or immediately if you notice any signs of damage, to prevent catastrophic engine failure from water ingestion.
Q: OEM vs. Aftermarket?
A: 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.
Q: How fast do you ship and how much does it cost?
A: 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.
Q: What is your warranty and return policy?
A: 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.