T-H Marine CMC Top Transom Washer Plate, 12-7/8 Inch Hole Centers, 6061-T6 Aluminum

The T-H Marine CMC Top Transom Washer Plate is a load-distributing backing plate for transom-mounted tilt and trim units and jack plates. It is machined from strong 3/8 inch 6061-T6 alloy aluminum, not cast aluminum, giving it the strength to handle the mounting loads of high performance engines without deforming. Bolting this plate against the inside of the transom spreads the clamping load of the mounting bolts across a wider area of fiberglass, so the bolt heads do not dig in, bite into, or crush the transom material over time. This is especially important on boats running powerful engines, where concentrated point loads from bolts alone can crack gelcoat or compress the transom core.

This is the top plate in a matched pair, with 12-7/8 inch hole centers sized to line up with standard tilt and trim and jack plate mounting patterns. A companion CMC Bottom Transom Washer Plate is sold separately under a different part number with 9-7/8 inch hole centers, so be sure to order the correct plate for the position you are reinforcing. The plate is a simple, purpose-built piece of hardware: no moving parts, no finish to wear off, just a solid aluminum backing plate designed to be installed once and left in place for the life of the transom mounting hardware.

Specifications

• Brand: T-H Marine CMC
• Manufacturer Part Number: 20022
• Material: 3/8 inch 6061-T6 alloy aluminum (not cast aluminum)
• Hole Centers: 12-7/8 inch
• Position: Top transom washer plate
• UPC: 733572020022
• Weight: 1 pound

Fitment

• Designed for transom mounting locations using a 12-7/8 inch hole center pattern, matching standard CMC tilt and trim units and jack plates.

Frequently Asked Questions

What is the T-H Marine CMC Top Transom Washer Plate used for? It is a backing plate, part number 20022, installed on the inside of a boat transom to spread the clamping load of tilt and trim or jack plate mounting bolts over a wider area so the bolts do not bite into or crush the transom.

What is this plate made of? Part number 20022 is machined from 3/8 inch 6061-T6 alloy aluminum, not cast aluminum, which gives it the strength to handle high performance engine mounting loads without deforming.

What are the hole centers on this washer plate? The hole centers measure 12-7/8 inch, matching the mounting pattern of standard CMC tilt and trim units and jack plates.

Is this the top or bottom transom washer plate? This is the top transom washer plate, part number 20022. A separate CMC Bottom Transom Washer Plate with 9-7/8 inch hole centers is sold under a different part number, so make sure to order the plate that matches the position you are reinforcing.

How much does the Top Transom Washer Plate weigh? Part number 20022 weighs 1 pound.

Is the plate cast or machined aluminum? It is not cast aluminum. The CMC Top Transom Washer Plate, part 20022, is made from strong 3/8 inch 6061-T6 alloy aluminum for better strength and load distribution.

Why would I need a transom washer plate instead of just tightening the mounting bolts directly? Direct bolt tightening without a backing plate concentrates load at each bolt head, which can bite into the transom over time, especially with high performance engines; the CMC Top Transom Washer Plate spreads that load evenly across the transom surface.

Does this washer plate come with mounting hardware? Part number 20022 is the aluminum washer plate itself; it is used together with the mounting bolts of the tilt and trim unit or jack plate being installed.

Will this fit any jack plate or tilt and trim unit? The CMC Top Transom Washer Plate, part 20022, is sized to a 12-7/8 inch hole center pattern, matching standard CMC tilt and trim and jack plate mounting.

Is the T-H Marine CMC Top Transom Washer Plate genuine or aftermarket? Part number 20022 is a genuine T-H Marine CMC component, manufactured to the same 12-7/8 inch hole center pattern used across CMC's tilt and trim and jack plate mounting hardware.