 Acrostef Tue 07 Jul 2026 08:18:09 | I’ve finally managed to prop up my Manta to replace the centerboard. I’ve located the bolt on the front right, but both the centerboard and the bolt itself are heavily rusted. Can anyone tell me where the threaded section of the bolt is located? Is the bolt threaded only at the tip—meaning it secures into the left side of the keel—or is it threaded just below the head—meaning the threads are on the right and there is simply a plain hole on the left? Knowing this would really help me plan how to tackle the job. Is this supposed to be an Allen bolt? I only see a round hole—either rusted away or damaged by previous owners.
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 Mark Wed 08 Jul 2026 07:26:13 | On mine, it was a plain hole on the bolt head side of the keel and it was threaded on the other side. It was all badly corroded, the bolt sheared and I had to use a hacksaw blade either side of the centre plate to cut away the rest of the bolt. In the photo, your centre plate looks a a bit low, mine sits flush with the bottom of the keel, so someone might have done something on it before and the pivot bolt might not be threaded the same as mine was. |
| Acrostef Thu 09 Jul 2026 10:35:26 | Okay Marc, thanks a lot. The photo gives a misleading impression of the centerboard. Normally, it sits flush with the bottom of the keel. What you're seeing is the centerboard gradually starting to come loose—still a bit of work to do there  . |
