90880A2 Mercruiser Exhaust Elbow | Genuine Used Part

🔧 Product Description

Genuine MerCruiser 3.7L Exhaust Elbow / Riser Assembly - Part Number: 90880A2

A genuine cast-iron exhaust elbow used on MerCruiser 3.7-litre and 224 CID inline four-cylinder sterndrive engines.

The component mounts above the exhaust manifold and forms part of the closed-cooling and wet-exhaust system. It directs exhaust gases into the exhaust hose while allowing cooling water to enter the downstream exhaust stream.

The casting may be marked 90879, while 90880A2 is the complete MerCruiser service assembly.

⚙️ Key Features

• Genuine MerCruiser 3.7L exhaust elbow
• Correct service part number 90880A2
• Associated casting number 90879
• Cast-iron water-jacketed construction
• Multiple verified aftermarket replacements available

🚤 Compatibility

Commonly used on

• MerCruiser aluminium-block 3.7L inline four-cylinder engines
• Closed-cooled sterndrive packages using the 90880A2 elbow

Typically suits

• Engine models:
• MerCruiser 165 2BBL - 1987, serial 0B434941 to 0B774251
• MerCruiser 170 2BBL - 1985-1986, serial 6916779 to 0B434940
• MerCruiser 180 4BBL - 1987, serial 0B436391 to 0B775248
• MerCruiser 190 4BBL - 1985-1986, serial 6916779 to 0B436390
• MerCruiser 470 late-production 3.7L
• MerCruiser 488
• MerCruiser 3.7L - 1988-1989
• MerCruiser 3.7LX - 1988-1989
• Engine Type: MerCruiser 3.7-litre / 224 CID inline four-cylinder petrol sterndrive
• Year Range: Approximately 1983 - 1989

🔌 Function

The elbow transfers exhaust gases from the manifold into the wet-exhaust hose and introduces cooling water to reduce exhaust temperature downstream.

⚠️ Common Signs of Failure

• Internal rust restricts exhaust or cooling-water flow
• Coolant or raw water enters the exhaust passage
• External cracking or severe corrosion
• Engine overheats under load
• White steam or water appears where it should not
• Elbow gasket leaks at the manifold joint

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 90880A2 documented MerCruiser service assembly
• 90879 associated cast-body number
• No later Mercury supersession confirmed; the OEM assembly is obsolete

OEM / Related Numbers

• 90880A2
• 90880-A2
• 90879
• Related elbow-to-manifold gasket
• Related closed-cooling reservoir and filler-cap components
• Related exhaust hose and clamps

Aftermarket / Verified Equivalents

• Sierra: 18-1905
• Barr Marine: MC-20-90880
• OSCO: 0879
• Aqua Power: 5725

📦 Condition

• Genuine used part
• Removed from running engine where applicable
• In good working condition unless otherwise stated