I have not seen this problem mentioned, but I've had the problem 4 times now. The ratchet system inside the oil cap fails. As a result, you can't just unscrew the cap. I had to break off the top, then epoxy weld the top to the piece still inside the valve cover to get the cap off. You can get the cap off this way, but it may not be straight unless you hold it till the epoxy. I had another spare in my parts bin so I used it. The bad one is the one with the yellow lettering.
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