CDI Unit / Ignition Module for Mariner Outboards

High-quality marine-grade aftermarket CDI ignition unit for selected Yamaha-built Mariner 9.9 HP, 15 HP, 20 HP and 25 HP 2-stroke outboard engines.

Designed as a replacement for Mercury / Mariner references including:

43077M / 43077T / 430775 / 430775M

This CDI family also cross-references to Yamaha 695-85540 ignition modules used on the corresponding Yamaha-derived engine platform.

Fits Selected Mariner 2-Stroke Outboards

9.9 HP

Selected:

Mariner 9.9C

15 HP

Selected models including:

Mariner 15C
Mariner 15K
Mariner W15

20 HP

Selected:

Mariner 20C

25 HP

Selected:

Mariner 25C

Fitment Summary

HP	Selected Mariner Models	Engine
9.9 HP	9.9C	2 Stroke
15 HP	15C / 15K / W15	2 Stroke
20 HP	20C	2 Stroke
25 HP	25C	2 Stroke

⚠️ IMPORTANT

These are selected Yamaha-derived Mariner outboards.

This CDI should not be assumed to fit every Mercury or Mariner 9.9 HP, 15 HP, 20 HP or 25 HP engine.

Replaces Mercury / Mariner Part Numbers

430775
430775M
43077M
43077T
96450M

Yamaha Cross Reference

This CDI family cross-references to selected Yamaha ignition units including:

695-85540-10
695-85540-10-00
695-85540-11
695-85540-11-00
695-85540-12
695-85540-12-00

Also associated with:

TIA01-36A

These Yamaha references are particularly useful when identifying the Yamaha-built Mariner engine family.

Additional Aftermarket Cross References

Sierra 18-5131
CDI Electronics 117-695-11
CDI Electronics 17-69511
Recmar REC695-85540-11

Yamaha-Built Mariner Engines

This is particularly important when selecting this CDI.

During this period, selected Mariner small outboards were based on Yamaha engine designs and therefore use Yamaha-family ignition components.

The CDI may therefore carry or cross-reference to a Yamaha 695-85540 number even though it is fitted to a Mariner outboard.

Do NOT order by horsepower alone.

Other Mercury / Mariner engines with the same horsepower can use completely different ignition systems.

Product Features

Marine-grade aftermarket CDI ignition unit
Suitable for selected Yamaha-built Mariner outboards
Selected 9.9 HP applications
Selected 15 HP applications
Selected 20 HP applications
Selected 25 HP applications
2-stroke applications
Replacement for 43077M
Replacement for 43077T
Replacement for 430775
Replacement for 430775M
Cross-references to Yamaha 695-85540 family
Direct replacement for compatible applications
New aftermarket ignition component

What Is the CDI Unit?

The CDI – Capacitor Discharge Ignition – unit is an important component of the outboard's ignition system.

It stores and releases electrical energy to control the spark delivered to the ignition system.

A faulty CDI unit can be associated with symptoms such as:

No spark
Weak or intermittent spark
Difficult starting
Misfiring
Engine cutting out
Loss of ignition when hot
Irregular engine operation

Important

These symptoms do not automatically mean that the CDI is faulty.

Similar problems can be caused by the stator, trigger/pulser components, ignition coils, stop circuit, wiring or poor electrical connections.

Proper diagnosis is recommended before replacing the CDI unit.

⚠️ IMPORTANT – Check Before Ordering

Do NOT order this CDI simply because your engine is:

9.9 HP
15 HP
20 HP
25 HP

The same horsepower can have several completely different engine and ignition-system designs.

Before purchasing, please check:

Mariner engine model
Horsepower
2-stroke engine
Engine serial number
Original CDI part number
Wiring configuration
Electrical connectors
Mounting arrangement

Ideally, match your original CDI to one of these references:

430775

430775M

43077M

43077T

96450M

or the corresponding Yamaha:

695-85540-10 / 11 / 12

⚠️ Appearance Does Not Confirm Fitment

If the CDI unit looks the same as the one fitted to your engine, this does not always mean it is the correct part for your outboard.

Different CDI units can look very similar externally but have different internal specifications and wiring.

Please check the original part number and engine details before ordering.

If you are unsure, contact SSI Marine and we will be happy to help.

Before Replacing Your CDI Unit

If your engine has an ignition problem, we recommend checking the complete ignition system before installing a replacement CDI.

Check:

Stator / source coil output
Trigger / pulser coil
Ignition coils
Spark plugs
Spark plug caps and leads
Stop / kill circuit
Engine earth / ground connections
CDI wiring
Electrical connectors
Burnt or corroded terminals
Damaged wiring

A fault elsewhere in the ignition system can produce symptoms similar to a failed CDI unit.

Aftermarket Replacement Part

This is a high-quality marine-grade aftermarket replacement part.

It is not a genuine Mercury, Mariner or Yamaha component.

OEM manufacturer names and part numbers are provided for identification and compatibility reference only.

The component is designed as a replacement for compatible Mariner applications using the part numbers listed above.

Buyer Responsibility

It is the buyer's responsibility to confirm compatibility before purchasing.

Please check:

Engine manufacturer
Horsepower
Exact engine model
2-stroke engine type
Engine serial number
Original CDI part number
Electrical connections

If you are unsure, contact SSI Marine before ordering. Our technical team will be happy to help identify the correct CDI unit.

Why Buy From SSI Marine?

Marine-grade aftermarket & OEM-spec parts
Workshop-tested products
More than 10 years supplying and working with outboard engines
Same-day dispatch before 1 PM Monday–Friday
Royal Mail Tracked 24
UK stock
Collection available from Leigh, Greater Manchester
Technical support from experienced outboard specialists
Workshop open Monday–Friday, 9 AM–5 PM

9.9 HP 15 HP 20 HP 25 HP Mariner Outboard 2 Stroke CDI Unit 43077M 43077T 430775M