I have been having the most difficult time with the alignment of my 1988 mercruiser 5.7/alpha one combination. I guess it is important to note that this was a complete restoration from a completely removed floor and transom that were quit severely rotted. I replaced all of the stringers, floor, transom and new philipine mahogany engine mounts. I add this because although a was very meticulous with regard to measurements and maintaining the original design. In my opinion and by digital caliper measurements all around the transom cutout revealed a very uniform transom thickness after installation. I seem to have an alignment issue that is a left to right rather than up and down adjustment. I am able to put an adjustment tool in all the way but it does require extra effort. Not like a sledge hammer but both hands and elbow grease. I completed the restoration the middle of last season. and was anxious to put several years of work in the water for at least some of the season. actually everything worked out fine for the rest of the season, no problems at all. when I took it out of of winter storage this year I gad a gimball bearing squealing and was satisfied with a good greasing. i then felt a small vibration when It idled and above while I had the ears on. and thought I would just change the gimbal bearing to be safe. a difficult to align Again much effort to insert the alignment tool. did the best allignment, I could as good or better that last year. put the drive on with much difficulty and have a larger vibration and a tapping sound and now an overheating issue. after tring to restart a stalled (Hot) engine, i notice bubbles of air being released from the outdrive as long as I continued to crank it over and the tink became like a clank after it finally restarted. pulled the boat out, removed the drive. With a water supply connected, the engine ran great no load and no over heating problem. So i inserted the alignment tool with somewhat less difficulty and started the engine with the the tool inserted to eliminate the engine right away as the source of the clanking noise, but to my surprise the noise seems to be coming from the rear of the engine. I do not know if a damaged coupler could make such a sound or a newly installed gimbal bearing that wasn't up for a less than perfect alignment, or last but not least could this group of miss-alignments have caused a flywheel/crankshaft damage. P.S. the coupler was brand new last year, and still appears visually to still have nice square cut splines and there appears to be no damage to the input shaft. Please help. |
Last edited: