Reply To: ’57 7.5 impeller replacement

[Don]

aquasonic wrote:

Negative on removing the driveshaft roll pin. If it’s in good condition, leave it be. When you disconnect the shift rod and drop the gearcase, remove the impeller housing screws, and the driveshaft can be pulled from the gearcase. The impeller and housing can be removed from the bottom of the driveshaft after the impeller key is removed.

Yep, this is the easiest way to do it for sure.  Trying to remove that pin is a pain, and it will need to be replaced afterwards…  I hear ya about that short screw in the rear of the powerhead, some of the engines are like this, others seems to have screws all the same length.  Needless to say, if yours has a shorter screw, use it in the rear/center power head threads.  Be sure the clean all those threads and use some sort of grease/sealer on the threads during reassembly.

I don’t see any of the lower seal components present on top of the driveshaft in your picture.  Please be sure you have all the components and they are reassembled properly, be sure to replace the big round gasket and the little oring that sets inside the carbon seal.   Missing parts/improper assembly of this lower seal is a leading factor in the slow death of many of these powerheads…