Martyr Zinc Block Anode Mercury CMT-43994Z

The Martyr CMT-43994Z is a zinc block-style sacrificial anode for select Mercury and MerCruiser applications. Current listings commonly identify it as CM43994Z, a Mercury replacement-style block anode associated with Mercury part 43994 / 43994A1 references. It is designed to help protect exposed drive or bracket-related metal components from galvanic corrosion in saltwater service.

This is a zinc anode, which makes it the correct material choice for saltwater use. Published dimensions across current listings are consistently about 4.0 in. x 3.1 in. x 1.5 in. (approximately 101.6 x 78.7 x 38.1 mm).

Key Features

• Zinc sacrificial block anode
• Martyr reference: CM43994Z
• Common Mercury reference: 43994 / 43994A1
• Designed for saltwater corrosion protection
• Approx. dimensions: 4.0 in. x 3.1 in. x 1.5 in.
• Block / wedge-style anode format used on select Mercury / MerCruiser applications

Engine Compatibility
Current fitment references most strongly associate this anode with Mercury / MerCruiser sterndrive applications, including Alpha Gen II and some Bravo references, rather than a broad modern outboard fitment listing. Because seller titles can vary, the safest match is by OEM part number and existing anode shape instead of title wording alone.

Serial Number Fitment Notice
Please verify fitment using your Mercury or MerCruiser serial number and compare the installed anode shape and mounting pattern before ordering. This is especially important because current listings tie this part more clearly to sterndrive and gimbal/block applications, and product naming can sometimes blur outboard versus sterndrive usage. Matching by 43994 / 43994A1 / CM43994Z is the safest approach.

When This Part Needs Replacement
Replace this anode when it is heavily wasted, pitted, cracked, loose, or significantly reduced in size. Mercurys current anode maintenance guidance says anodes provide less protection as they dissolve and should be changed when they are about 50% consumed.

Installation Notes
Install the anode on a clean bare-metal contact surface and do not paint it. Confirm the hole spacing and mounting pattern against your existing part before installation. Current listings show this as a multi-hole block anode, but exact hole-count descriptions vary by seller, so physical comparison before ordering is recommended.

Alternate / Superseded Part Numbers

• CM43994Z
• 43994
• 43994A1

Parts Desk Insight
This is the kind of part that is easy to ignore because it is just a simple cast block, but it is protecting much more expensive metal around it. One interesting detail is that current listings repeatedly place this anode in the gimbal plate / block / wedge category, which is a good clue that matching by shape and mounting pattern matters more than relying on a short product title alone.

Shipping
Shipping: Ships same or next day for fast Canada wide shipping.