# 27997772 Mercury MerCruiser Rear Riser Open Gasket | Genuine Quicksilver OEM Part

🔧 Product Description

  

Genuine Quicksilver Rear Riser / Exhaust Elbow Open Gasket - Part Number: 27-997772

  

A genuine Quicksilver open-style rear riser / exhaust elbow gasket for selected MerCruiser standard cooling exhaust systems. This gasket seals the exhaust riser or elbow joint on older MerCruiser inline, 4-cylinder and V8 log-style exhaust applications.

  

⚙️ Key Features

  

• Genuine Quicksilver OEM exhaust gasket

• Correct Mercury part number 27-997772

• Open-style rear riser / exhaust elbow gasket

• Used on selected MerCruiser 120, 140, 165 L6, 470, 3.0LX and early V8 exhaust systems

• Commonly supplied as a pair in aftermarket Sierra equivalent packs

  

🔄 Supersession & Cross Reference

  

OEM Supersession Chain:

  

• 27-997772 current / later open gasket reference

• 27-997772 supersedes / replaces earlier 27-997771 and 27-99777 family references where applicable

  

OEM / Related Numbers:

  

• 27-997772

• 997772

• 27997772

• 27-997771

• 997771

• 27-99777

• 99777

• 27-99777B2

• 27-52076

  

Aftermarket / Verified Equivalents:

  

• Sierra: 18-2833

• Sierra: 18-2833-9

• GLM: 31520

• Mallory: 9-61407

• Recmar: REC27-99777Q02

  

🚤 Compatibility

  

Commonly used on:

  

• MerCruiser standard cooling rear riser / exhaust elbow applications

• Older MerCruiser log-style manifold and riser systems

  

Typically suits:

  

• Engine models:

• MerCruiser 120 MCM applications where 27-997772 is specified

• MerCruiser 120 / 140, 1982-1995 rear riser gasket applications

• MerCruiser 140 / 3.0L rear riser gasket applications

• MerCruiser 3.0L / 3.0LX rear riser open gasket applications

• MerCruiser 165 inline 6-cylinder rear riser applications

• MerCruiser 470 3.7L, 1976-1982 rear riser applications

• MerCruiser V8 5.0L / 5.7L early engines, 1982 and earlier

• MerCruiser V8 5.0L / 5.7L, 1977-1982 log-style manifold applications

• MerCruiser Ford V8 exhaust elbow applications where 27-997772 is specified

  

• Engine Type: MerCruiser petrol sterndrive / inboard

• System Type: Rear riser / exhaust elbow open gasket

  

🔌 Function

  

The gasket seals the exhaust riser / elbow joint while allowing correct exhaust and cooling water flow through the standard cooling exhaust system.

  

Common signs of failure:

  

• Water leak at riser joint

• Exhaust leak or fumes near manifold

• Rust staining between riser and manifold

• Overheating from restricted or leaking exhaust water passage

• Gasket replacement required during riser removal

  

📦 Condition

  

• Genuine Quicksilver part

• Brand new

• Supplied in original or equivalent packaging

## Details

- **Price:** 17.2 AUD
- **Vendor:** Quicksilver
- **Tags:** Quicksilver Marine Parts | Oils Service Kits & Engine Components

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 17.20 AUD | In stock |

## Images

- 27997772 Mercury MerCruiser Rear Riser Open Gasket | Genuine Quicksilver OEM Part

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> Source: [Sawley's Auto and Marine](www.sawleysautoandmarine.com.au/products/27997772-mercury-mercruiser-rear-riser-open-gasket-genuine-quicksilver-oem-part)
> Updated: 2026-05-17