332-777BC Mercury Switch Box | Genuine Used Part

🔧 Product Description

Genuine Mercury Switch Box - Part Number: 332-7778C

A genuine Mercury switch box / CDI ignition module used on selected Mercury and Mariner 3-cylinder and 6-cylinder two-stroke outboards. This ADI switch box controls ignition discharge from the stator and trigger circuits to the ignition coils.

⚙️ Key Features

• Genuine Mercury switch box

• Listed as 332-777BC and matching the 332-7778C switch-box number family

• Used on selected Mercury / Mariner 3-cylinder and V6 two-stroke ignition systems

• Cross-references with CDI Electronics 114-7778 and Sierra 18-5775

• Match by original switch-box number, engine serial range and wiring layout

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• 332-7778A12 later Mercury switch box reference

• 332-7778A9 earlier Mercury switch box reference

• 332-7778A7 earlier Mercury switch box reference

• 332-7778A6 earlier Mercury switch box reference

• 332-7778A5 earlier Mercury switch box reference

• 332-7778A3 earlier Mercury switch box reference

• 332-7778A1 earlier Mercury switch box reference

• 332-7778C related Mercury switch box reference

• 332-7778 base Mercury switch box reference

• 332-5524A1 related Mercury switch box reference

OEM / Related Numbers:

• 332-777BC

• 332-7778C

• 7778C

• 332-7778

• 332-7778A1

• 332-7778A3

• 332-7778A5

• 332-7778A6

• 332-7778A7

• 332-7778A9

• 332-7778A12

• 332-5524A1

• Switch box

• CDI module

• ADI ignition switch box

Aftermarket / Verified Equivalents:

• CDI Electronics: 114-7778

• Sierra: 18-5775

• WSM: 114-7778

🚤 Compatibility

Commonly used on:

• Mercury / Mariner 3-cylinder and V6 two-stroke ADI ignition systems

Typically suits:

• Engine models:

• Mercury 50HP 3-cylinder - 1985-1990, serial 6586625 to 0D000749

• Mercury 65HP 3-cylinder - 1976-1979, serial 4382057 to 4571651

• Mercury 70HP 3-cylinder - 1977-1993, serial 4571652 to 0D283221

• Mariner 70HP 3-cylinder - serial 5128280 and later

• Mercury 105 Jet - 1992-1996, serial 0D082000 to 0G840500

• Mercury 115HP 6-cylinder - 1979-1989, serial 5314656 to 0C099999

• Mercury 135HP V6 - 1976-1999 model-controlled applications

• Mercury 150HP V6 - 1976-1999 model-controlled applications

• Mercury 175HP V6 - 1976-1999 model-controlled applications

• Mercury 200HP V6 - 1976-1999 model-controlled applications

• Mercury 225HP V6 - 1976-1999 model-controlled applications

• Mercury 275HP V6 - model-controlled switch-box applications

• HP Range: commonly 50HP - 275HP depending on cylinder count and ignition layout

• Engine Type: Mercury / Mariner 3-cylinder and V6 two-stroke ADI ignition system

• Year Range: approximately 1976 - 1999 depending on model

• Serial Range: confirmed examples include 6586625 to 0D000749, 4382057 to 4571651, 4571652 to 0D283221, 0D082000 to 0G840500, and 5314656 to 0C099999. Match by exact engine serial number and original switch-box number.

🔌 Function

The switch box stores and releases ignition energy, using stator and trigger input to fire the ignition coils at the correct timing point.

Common signs of failure:

• No spark on one or more cylinders

• Weak or intermittent spark

• Engine loses spark when warm

• Misfire under load

• Poor acceleration from ignition drop-out

• Spark returns when a known-good switch box is fitted

• Burnt, cracked or corroded switch-box terminals

📦 Condition

• Genuine used part

• Removed from running engine where applicable

• In good working condition unless otherwise stated