Well I have a manual and want to drop the L/U on my 1963 Merc 500 50hp and check out the impellor. So the first thing I try to remove is the trim tab. Going by the manual I look in the access hole to loosen the allen head screw that holds the trim tab in place and what I see is what appears to be an allen head that has been rounded off. So I fiddle with the trim tab and find it is not so tight, in fact I can rotate it about 30 degrees either way and the allen head or whatever it is also rotates. In fact I cannot figure out how I would get the allen head out even if it was not messed up. The darn thing has a diameter larger than the access hole. Does anyone know what the size of the allen head is suposed to be i.e., 3/8" or what ? I could cut away a section of the L/U with a dremel to get at the problem but that would be a last desperate act. Has anyone encountered this before ? Help !
