Problems w ~ 51 flathead in 46 Mercury Woodie

[pistonbroke]

I found it cheaper and esier just to have my 53 merc borg and beck flywheel redriled for the correct clutch in my 41, As for your rattel ,your wrench guy should have seen wear marks on the flywheel bolts and the springs in the disk if that was the problem. There would be an odd wear paterns on the presureplat fingers if that were a problem. I hope this is not your problem but I have a old 390 in my F100 that has a worn out thrust bearing on the crank and on cold days it makes the same noise at the same time you are describing. Its been that way for over twenty years and never changes. Like you I thought it was clutch related at first. Tim