Exhaust Manifold Riser Gasket 27-18272 27-97863 for MerCruiser 3.7L 3.7LX 470 165 170 180 190 HP Sierra 18-0881
Exhaust Manifold Riser Gasket 27-18272 27-97863 for MerCruiser 3.7L 3.7LX 470 165 170 180 190 HP Sierra 18-0881
Product Overview
Exhaust manifold riser gasket, a direct replacement part for MerCruiser 3.7 L four cylinder marine engines, the 224 CID motor sold as the 470 and the 165, 170, 180 and 190 HP versions. It replaces MerCruiser 27-18272 and 27-97863 and crosses to Sierra 18-0881. The gasket weighs 70 g and ships flat in a 180 mm x 160 mm x 10 mm envelope (7.09 in x 6.30 in x 0.39 in).
This gasket goes between the exhaust manifold and the riser on the four cylinder 3.7 L engine. It is a single gasket, not a manifold set, and the manifold to head gasket is a separate part.
It only fits Mercury built 224 CID engines with aluminium exhaust manifolds. The GM based V6 and V8 engines use a different riser pattern, and the cast iron manifold versions take a different gasket, so check both before ordering.
Fitment is by engine serial number rather than by year alone, because Mercury changed the riser pattern part way through 1987. The serial ranges are in the table below.
Specifications
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Exhaust manifold riser gasket |
| MerCruiser Part Numbers | 27-18272, 27-97863 |
| Sierra Cross Reference | 18-0881, also listed as 18-0881-1 |
| Fits | MerCruiser 3.7 L and 3.7LX, 224 CID four cylinder |
| Fits Horsepower | 165 HP, 170 HP, 180 HP and 190 HP |
| Years | 1985 to 1989 |
| Manifold Type | Aluminium exhaust manifold only |
| Engine Origin | Mercury built 224 CID, not GM based |
| Package Contents | 1 x exhaust riser gasket |
| Country of Origin | Taiwan |
| Net Weight | 70 g including packaging |
| Pack Size | 180 mm x 160 mm x 10 mm |
| Pack Size In Inches | 7.09 in x 6.30 in x 0.39 in |
| Warranty | 3 year |
OEM Cross Reference
| Brand | Part Numbers |
|---|---|
| MerCruiser | 27-18272 |
| MerCruiser | 27-97863 |
| Mercury | 27-18272, 27-97863 |
| Sierra | 18-0881, 18-0881-1 |
Compatible Engines
| Engine | Horsepower | Serial Range | Years |
|---|---|---|---|
| MerCruiser 3.7 L, 224 CID | 165 HP | 0B434941 to 0B774251 | 1987 |
| MerCruiser 3.7 L, 224 CID | 170 HP | 6916779 to 0B434940 | 1985 to 1986 |
| MerCruiser 3.7 L, 224 CID | 180 HP | 0B436391 to 0B775248 | 1987 |
| MerCruiser 3.7 L, 224 CID | 190 HP | 6916779 to 0B436390 | 1985 to 1986 |
| MerCruiser 3.7 L, 224 CID | 3.7 L | 0B774252 and up | 1988 to 1989 |
| MerCruiser 3.7LX, 224 CID | 3.7LX | 0B775249 and up | 1988 to 1989 |
What's Included
| Component | Detail | Qty |
|---|---|---|
| Exhaust riser gasket | 27-18272, direct fit | 1 |
| Manifold to head gasket | Not included | 0 |
| Riser bolts and studs | Not included, reuse the originals | 0 |
Signs The Riser Gasket Has Failed
| What You See | What It Means | What To Do |
|---|---|---|
| Water in the oil | Riser gasket leaking into the block | Fit the new gasket |
| Exhaust leak ticking under load | Gasket blown at the joint | Fit the new gasket |
| Rust streaks at the manifold joint | Water tracking past the gasket | Fit the new gasket |
| Milky oil after a run | Cooling water reaching the sump | Fit the new gasket and change the oil |
| White deposit round the riser | Dried salt water from a leak | Fit the new gasket |
| Manifold off for other work | Cheap to renew while apart | Fit the new gasket |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Read the engine serial number and check the table above |
| 2 | Confirm the engine has an aluminium exhaust manifold |
| 3 | Drain the cooling system and disconnect the battery |
| 4 | Unbolt the riser from the manifold and separate the joint |
| 5 | Scrape both faces clean and check them for pitting |
| 6 | Fit the new gasket dry and line up the water passages |
| 7 | Torque the riser bolts evenly to the Mercury figure for your engine |
| 8 | Refill, run on muffs and check the joint for leaks and for water in the oil |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | 3 year |
| Packaging | Sealed retail packaging |
Before You Buy
- Fits MerCruiser 3.7 L 224 CID four cylinder engines from 1985 to 1989
- Fits 165 HP and 180 HP models from serial 0B434941 and 0B436391
- Fits 170 HP and 190 HP models from serial 6916779
- Fits 3.7 L from serial 0B774252 and 3.7LX from serial 0B775249
- Replaces MerCruiser 27-18272 and 27-97863
- Crosses to Sierra 18-0881, also listed as 18-0881-1
- Aluminium exhaust manifold only
- Mercury built 224 CID engines, not GM based engines
- 70 g with packaging, envelope 180 mm x 160 mm x 10 mm
- 30-Day Easy Returns
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Before You Buy
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