Exhaust Elbow Gasket – Fits MerCruiser 120, 140, 2.5L, 3.0L & V8 Models (Replaces 27-997771, Sierra 18-2833-9)
Exhaust Elbow Gasket – Fits MerCruiser 120, 140, 2.5L, 3.0L & V8 Models (Replaces 27-997771, Sierra 18-2833-9) is backordered and will ship as soon as it is back in stock.
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Exhaust Elbow Gasket – Fits MerCruiser 120, 140, 2.5L, 3.0L & V...
Exhaust Elbow Gasket – Fits MerCruiser 120, 140, 2.5L, 3.0L & V8 Models (Replaces 27-997771, Sierra 18-2833-9) is backordered and will ship as soon as it is back in stock.
Product Details
This Exhaust Elbow Gasket is a single replacement gasket designed to seal the exhaust manifold-to-riser or elbow connection on compatible MerCruiser wet-joint exhaust systems. It is listed for select MerCruiser 120, 140, 2.5L, 3.0L and V8 applications. Confirm the engine model, exhaust design and original gasket shape before ordering.
This gasket replaces MerCruiser part number 27-997771 and is listed as an interchange for Sierra 18-2833-9. Reference numbers describe potential replacement relationships; always compare the original part and verify the specific engine application.
- For compatible wet-joint exhaust connections.
- Seals the joint between the exhaust manifold and exhaust riser or elbow.
- Composite fiber gasket construction for marine exhaust service.
- Sold as one individual exhaust elbow gasket.
Part Number Matrix
Use these listed replacement references to help identify the correct gasket.
| Brand | Part Number |
|---|---|
| MerCruiser | 27-997771 |
| Sierra | 18-2833-9 |
Engine & Model Compatibility
The available product record identifies this gasket for select MerCruiser 120, 140, 2.5L, 3.0L and V8 applications. Exact fitment can vary by engine year, exhaust-manifold design and serial-number range, so verify the application against the engine service information and the original gasket before installation.
| Brand | Application | Engine Information | Exhaust System | Replacement Reference | Fitment Notes |
|---|---|---|---|---|---|
| MerCruiser | 120 | 2.5L-class application | Wet-joint | 27-997771 | Verify year, serial range and gasket profile. |
| MerCruiser | 140 | 3.0L-class application | Wet-joint | 27-997771 | Verify year, serial range and gasket profile. |
| MerCruiser | 2.5L / 3.0L | Selected I4 applications | Wet-joint | 27-997771 | Confirm the manifold and riser connection before ordering. |
| MerCruiser | V8 | Selected V8 applications | Wet-joint | 27-997771 | Do not assume every V8 model uses this gasket; verify the original part. |
Technical Specs
- Product Type
- Exhaust Elbow Gasket
- Installation
- Wet-joint exhaust connection
- Connection
- Bolted manifold-to-riser or elbow joint
- Material
- Composite fiber gasket material
- Color
- Brown/tan, subject to production variation
- Fitting Type
- Exhaust elbow or riser to manifold
- Package Configuration
- Single gasket
What’s in the Box
- 1 x Exhaust Elbow Gasket
Installation Notes
- Ensure the engine is completely cool and disconnect the battery before starting work.
- Drain coolant or cooling water as required by the engine service procedure, then carefully remove the exhaust riser or elbow.
- Remove all remnants of the old gasket from both mating surfaces. Avoid scratching or distorting the manifold and elbow faces.
- Position the new gasket on the manifold and align all bolt holes and water passages. Install it dry unless the engine service manual specifies otherwise.
- Reinstall the exhaust riser or elbow and tighten the fasteners in the specified sequence and to the manufacturer’s torque values.
- Restore the cooling system as required, reconnect the battery and run the engine while checking for exhaust, coolant or water leakage.
Troubleshooting & FAQ
What are the signs of a failing exhaust elbow gasket?
Possible signs include water or coolant leakage at the manifold-to-riser joint, visible steam, exhaust odor, overheating or evidence of water entering an exhaust passage. Stop operation and inspect the joint if these symptoms occur.
Is this a wet-joint or dry-joint gasket?
This gasket is listed for wet-joint exhaust connections. Confirm the exhaust design and water-passage layout on your engine before ordering or installing it.
Can I reuse my old gasket?
No. Exhaust gaskets are generally single-use sealing components. Replace the gasket whenever the manifold or riser connection is disassembled.
Do I need sealant during installation?
Install the gasket according to the engine manufacturer’s service instructions. Do not apply sealant unless the applicable service manual specifically requires it.
Will this fit every MerCruiser 2.5L, 3.0L or V8 engine?
No universal fitment should be assumed. The gasket is listed for selected MerCruiser applications, and fitment may depend on the engine model, year, serial range and exhaust-manifold design. Compare the original gasket and verify the service information before purchase.
What happens if I use the wrong gasket?
An incorrect gasket can misalign water passages or fail to seal the exhaust connection, potentially causing leaks, overheating, corrosion or water intrusion. Confirm the part profile and application before installation.
Is this an OEM part?
This listing is for an aftermarket replacement gasket, not a MerCruiser-branded OEM component. It is listed as a replacement for MerCruiser 27-997771 and Sierra 18-2833-9.
Shipping speed and cost
Available shipping methods, delivery estimates and costs are shown at checkout and vary by destination.
Warranty and returns
Warranty and return eligibility are governed by the applicable store policies. Contact support with your order details if you need assistance.
Safety & Important Info
- Verify the engine model, year, serial range, original gasket shape and exhaust design before ordering.
- Do not operate the engine if exhaust, coolant or water leaks are present after installation.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended when removing or reinstalling marine exhaust components.
About Sea Sierra
- Marine Replacement Parts — We supply replacement components for a range of marine repair applications.
- Application-Focused Support — Verify model and part details before installation to help ensure the correct replacement.
- Convenient Fulfillment — Shipping options and delivery estimates are provided during checkout.
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