333-3213A3 Mercury Switch Box | Genuine Used Part

🔧 Product Description

Genuine Mercury Switch Box Assembly - Part Number: 333-3213A3

A genuine Mercury ignition switch box assembly used on selected early Mercury 4-cylinder Thunderbolt ignition systems. This 4-post switch box is associated with classic Mercury 500 / 50HP and Mercury 650 / 65HP two-stroke outboards and must be matched by original switch-box number and wiring layout.

⚙️ Key Features

• Genuine Mercury switch box assembly
• Correct Mercury part number 333-3213A3
• Early 4-post Thunderbolt ignition switch box
• Used on selected Mercury 50HP and 65HP 4-cylinder two-stroke engines
• Red / white / blue / green 4-post wiring layout must match the original unit

🚤 Compatibility

Commonly used on

• Early Mercury 4-cylinder two-stroke Thunderbolt ignition systems

Typically suits

• Engine models:
• Mercury 500 / 50HP 4-cylinder - 1968-1975
• Mercury 500 / 50HP - serial 4357640 to 5531629
• Mercury 50HP 4-cylinder Thunderbolt ignition
• Mercury 650 / 65HP 4-cylinder - late-1960s applications
• Mercury 65HP 4-cylinder Thunderbolt ignition
• HP Range: commonly 50HP - 65HP
• Engine Type: Mercury 4-cylinder two-stroke outboard with early Thunderbolt switch-box ignition
• Year Range: Approximately 1968 - 1975 for common 50HP / 65HP applications
• Serial Range: Mercury 500 / 50HP parts-family range includes serial 4357640 to 5531629; 65HP applications must be checked by original serial-numbered ignition diagram and 4-post switch-box wiring.

🔌 Function

The switch box stores and releases ignition energy to the coil circuit when triggered, allowing the engine to produce spark at the correct timing point.

⚠️ Common Signs of Failure

• No spark
• Weak or intermittent spark
• Engine starts then loses spark
• No-start after trigger, coil and wiring checks
• Spark returns when switch box is substituted
• Internal failure caused by age, heat or vibration
• Incorrect spark output from damaged terminals or wiring

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 333-3213A3 current Mercury switch box assembly reference
• 333-3213 related base switch box reference
• 3213A3 formatted Mercury switch box reference

OEM / Related Numbers

• 333-3213A3
• 3333213A3
• 3213A3
• 333-3213
• 3333213
• Switch box assembly
• Ignition switch box
• 4-post switch box
• Red / white / blue / green terminal layout

Aftermarket / Verified Equivalents

• Pro Marine: 19052
• Maxrules: 19052

📦 Condition

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