Marine-grade aftermarket transom and swivel bracket sacrificial anode for selected 40 HP and 50 HP Mercury / Mariner outboard engines.

Designed to help protect the outboard transom bracket, swivel bracket and associated metal components against galvanic corrosion.

Suitable for selected Lightning, Lightning XR, MXL Marathon, MXL SeaPro and 50MH engine models.

Main Part Number: 8239121

Available in Zinc

Fitment – Mercury / Mariner Outboards

40 HP Lightning – International

40 HP Lightning XR – International

40 HP MXL Marathon

40 HP MXL SeaPro

50 HP – 50MH

This anode is fitted to the transom/swivel bracket assembly.

Compatibility depends on:

Not every Mercury / Mariner 40 HP or 50 HP engine uses this anode.

Please check the original part number and mounting arrangement before ordering.

Replaces Mercury / Mariner Part Numbers

OEM part numbers are used for identification and compatibility reference only.

Important: This product is not the same as the smaller round anode 823912, which is used on different engine applications.

1 × Sacrificial Anode

Mounting hardware is not included unless otherwise specified.

Inspect the anode regularly during routine engine servicing.
Replace when approximately one-third or more of the original material has been consumed, or sooner if required.
Never paint or coat sacrificial anodes.
Ensure clean metal-to-metal contact at the mounting surface.
Check that the anode is securely fitted.

Before ordering, please confirm:

If the part looks the same as yours, this does not always mean it is the correct part for your outboard.

If unsure, please contact SSI Marine with your engine model and serial number for assistance.

Please confirm compatibility with your exact Mercury / Mariner engine model, serial number and transom bracket configuration before purchase.