# 860235A03 Mercury MerCruiser Exhaust Manifold assembly | Genuine Quicksilver OEM Part

🔧 Product Description

  

Genuine Quicksilver 3.0L Exhaust Manifold Assembly - Part Number: 860235A03

  

A genuine Quicksilver exhaust manifold assembly for MerCruiser GM inline 4-cylinder 3.0L petrol engines. This manifold is the later single-piece Vortec-head style log manifold used on 1990 and newer 3.0L / 3.0LX applications, helping route exhaust gases and cooling water through the marine exhaust system.

  

⚙️ Key Features

  

• Genuine Quicksilver OEM exhaust manifold assembly

• Correct Mercury part number 860235A03

• Used on MerCruiser GM 3.0L / 181 CID inline 4-cylinder engines

• Single-piece Vortec head style log exhaust manifold

• Replaces earlier 99798 and 806867 exhaust manifold references

  

🔄 Supersession & Cross Reference

  

OEM Supersession Chain:

  

• 860235A03 → Supersedes 806867A8

• 806867A8 → Supersedes 99798A18

• 99798A18 → Supersedes 99798A16

• 99798A16 → Supersedes 99798A9

• 99798A3 earlier OEM reference

  

OEM / Related Numbers:

  

• 860235A03

• 860235A04

• 806867A8

• 806867A3

• 99798A18

• 99798A16

• 99798A9

• 99798A3

• B-MC-1-860235

  

Aftermarket / Verified Equivalents:

  

• H2O: T-20956

• Sierra: 18-1956-1

• Barr: MC-1-860235

  

🚤 Compatibility

  

Commonly used on:

  

• MerCruiser GM 181 CID / 3.0L inline 4-cylinder exhaust systems

  

Typically suits:

  

• Engine models:

• MerCruiser 3.0L GM 181 I/L4, 1990 and newer applications using 860235A03

• MerCruiser 3.0LX GM 181 I/L4, 1990 and newer applications using 860235A03

• MerCruiser 3.0L 140HP 4-cylinder Vortec-head exhaust manifold applications

• MerCruiser 3.0L engines using MERCARB single idle air screw carburettor arrangement

• MerCruiser 3.0L exhaust manifolds replacing earlier end-cap style manifold layouts where 860235A03 is specified

• MerCruiser 3.0L petrol sterndrive engine packages requiring 860235A03 manifold assembly

  

• HP Range: commonly 135HP - 140HP 3.0L applications

• Engine Type: GM 181 CID / 3.0L inline 4-cylinder petrol engine

• System Type: Exhaust manifold / cooling water discharge assembly

  

🔌 Function

  

The exhaust manifold routes exhaust gases and cooling water away from the cylinder head and into the riser / exhaust outlet path.

  

Common signs of failure:

  

• External rust or water leakage

• Internal corrosion causing water intrusion

• Engine overheating from restricted water passages

• Exhaust leak or fumes around manifold

• Water staining, cracking or gasket failure at manifold joints

  

📦 Condition

  

• Genuine Quicksilver part

• Brand new

• Supplied in original or equivalent packaging

## Details

- **Price:** 1049.09 AUD
- **Vendor:** Quicksilver
- **Tags:** Quicksilver Marine Parts | Oils Service Kits & Engine Components

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 1049.09 AUD | In stock |

## Images

- 860235A03 Mercury MerCruiser Exhaust Manifold assembly | Genuine Quicksilver OEM Part

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> Source: [Sawley's Auto and Marine](www.sawleysautoandmarine.com.au/products/860235a03-mercury-mercruiser-exhaust-manifold-assembly-genuine-quicksilver-oem-part)
> Updated: 2026-05-17