Take a step back. Is the chain sized appropriately for the weight of the anchor and size of the boat? On two of our boats the previous owners used absurdly large chain. I think they were going for a short, heavy piece instead of a longer appropriate size. In any event, our problems were solved on both boats by adding the correct size of chain. Our rule of the thumb has always been to use anchor shackles one size larger than the chain, so for the 1/4" chain we have, I use 5/16" shackles. Both go through the anchor roller that came factory on our 27-3.