inspection port on holding tank

[cscheck]

Hello all ... been a few years since I've been on the board. Here's a pressing question about my CD33 holding tank. I want to replace the 4-inch inspection port on top of the tank. The old one is cracked and stained by rust. There are many 4-inch inspection plates for sale, but when you bring one home it turns out that every brand is somewhat different and doesnt match the existing screw holes.
My plate has HYMI molded into the under side. But I can find that when I search. Anybody recognize that name, or know a current piece that would match mine?
Thanks again. whenever I try to fix something I end up in one of these goose chases. I guess I could fill the old holes with epoxy and drill new ones, but I hate to do that.

Chris Scheck
cd33 Ragtime

[gonesail]

mine is a 1990 model. I found out the inspection port manufacturer is no longer in business and the port threads don't match anything you can get today

[bottomscraper]

I found a replacement at the Hamilton Marine store a few years ago. I had also found some that don't fit right (Beckson IIRC) The one that I got was in a Bomar package but was marked PYHI. The one I found was black but that almost seems more appropriate .

Anyway I think you can order them from Hamilton Marine:

Bomar Part Number: BOM-802
Hamilton Marine Order #: 104545

https://shop.hamiltonmarine.com/product ... -2440.html