42970A2 Mercury Attenuator Plate | Genuine Used Part

🔧 Product Description

Genuine Mercury / Mariner Three-Cylinder Sound Attenuator Plate - Part Number: 42970A2

A genuine Mercury sound-attenuator plate used at the front of selected 65 Jet, 70HP, 75HP, 80HP and 90HP three-cylinder two-stroke outboards. It forms the base of the air-silencer assembly and also provides mounting points for throttle components and, on updated installations, the voltage regulator.

⚙️ Key Features

• Genuine Mercury / Mariner sound attenuator plate
• Correct current part number 42970A2
• Casting number commonly marked 42873-C4
• Used on three-cylinder two-stroke outboards
• Supports matching attenuator cover 42969A3

🚤 Compatibility

• Mercury / Mariner 65 Jet three-cylinder
• Mercury / Mariner 70HP, 75HP, 80HP and 90HP three-cylinder families where listed
• Commonly documented on 65 Jet, 75HP and 90HP models
• Approximate year range: 1987-2006, with some later catalogue applications
• Fitment controlled by serial number and attenuator-cover configuration

🔌 Function

The plate supports the air-silencer cover, reduces induction noise, carries throttle-related hardware and provides the correct air path into the carburettors.

⚠️ Common Signs of Failure

• Plate is cracked or warped
• Mounting studs or threads are damaged
• Attenuator cover cannot latch correctly
• Throttle components bind
• Regulator mounting point is damaged
• Increased intake noise or loose hardware

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 429705 → Superseded by 42970A2
• 42970T and 42970T1 are related service formats cross-referenced to the same plate family
• 42873-C4 is the casting number, not a service supersession

OEM / Related Numbers

• 42970A2
• 429705
• 42970T
• 42970T1
• 42873-C4 casting
• 42969A3 matching attenuator cover
• 4002217 washer, 39519 cup and related latch / throttle hardware

Aftermarket / Verified Equivalents

• No verified complete branded aftermarket plate
• Used genuine Mercury plates are the direct replacement
• Aftermarket gaskets and carburettor service parts are available separately
• Some stator / regulator conversion kits specifically require the later 42970A2-style mounting plate

📦 Condition

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