I hauled out my Honda 7.5 four-stroke yesterday to try it on an inflatable I just bought at a garage sale. I haven't used the engine for three years and it's been in my basement.<br /><br />The engine was seized due to interference between the flywheel magnets and the core of the magneto and alternator, both of which are under the flywheel. I suspect that the flywheel, the magnets, or the magnet retainers rusted, and the rust expanded the dimensions of the magnet/retainer, and pushed them into the cores. With considerable force I got the engine turning, removed the flywheel, and cleaned the rust off of<br />the accessible surfaces of the magnet retainers and cores. It now rotated but I could still hear metal rubbing. I ran it a while, hoping that the interfering metal would wear away. Wrong! It generated enough heat to cause things to expand and seize up again. I need a better solution.<br /><br />Five things come to mind.<br /><br />1) Replace the flywheel with a new one or a used but non-rusty one. Pricey unless someone has a junker 7.5 and will sell me the flywheel for a low price.<br /><br />2) Turn down the inside of the flywheel a bit (actually the magnet retainers) to remove enough metal to eliminate the interference. Not too hard to do but I don't like the idea of thinning the retainers.<br /><br />3) Grind down the cores. I don't like this in the event that I ever do need to replace the flywheel since the core-magnet gap will then be larger than designed.<br /><br />4) Make a new bushing for the transformer core mount with an offset hole. Also not too hard and with the advantage that no metal is thinned.<br /><br />5) Remove the magnet retainers and magnets, clean the offending rust from the inside surfaces and reattach them. This looks a little tricky since the magnet retainers are riveted on and reattachment could be a challenge, especially maintaining flywheel balance.<br /><br />Has anyone had this problem? What was your solution? Anyone have a junker 7.5 and willing to sell me the flywheel?<br /><br />Thanks,<br />Bill W.
