I just swapped out the engine in my old boat. The old engine was a 1971 165 Mercruiser GM straight six. I put a 1974 Mercruiser 165 in its place. The old bell housing and coupler were taken off the old engine and placed on the replacement. The coupler had been replaced by a marine mechanic a year ago due to worn splines. He had also shimmed under the front motor mount about 3/4". He told me he couldn't raise it high enough. This didn't make sense to me because the stringer appears in good shape. The nuts on the front mount were frozen until I used heat and a big cheater bar. I don't think this guy did a proper alignment. I now have an alignment problem with the replacement engine. With the timing mark on the crank pulley at 12 o'clock the engine front shows too high. Alignment tool was coated with grease. It goes in a little more than an inch and there are spline marks on top of the shaft only. Rotate the engine 180 degrees and the alignment tool is able to slide in easy and bottom out. I think I have a bad coupler or cocked the flywheel during installation. What do you guys think? The other question I have is about the rear motor mounts. The metal sleave sticks out the bottom of the rubber a tiny bit. Maybe a little more than a 1/16". The underside of the metal bushing was rough, maybe knurled. Could this be the new style mount? There is approx. 1/4 inch gap between the top of the fiber washer and metal housing that the mount is in(replacement engine). This is with the spring washer installed and rear mounts tightened. Is it right to have that much space on top of the fiber washer? This is the first engine replacement I'm doing so I want to make sure it's done right.
