I must preface this with saying this is the type of question that brings out the religion in certain people (myself included?), so be ready for a lot of strong opinions. I will concede that we have some very experienced sailors on this site who have had E27s with outboards and are quite happy with them and have put them on in response to a failing inboard. That all acknowledged, I found that putting the Atomic 4 back into my prior E27 was one of the happiest things I ever did on that boat. To me, the usability and convenience and resale value all improved greatly with the inboard. I got really tired of messing around with a blasted engine hanging off the transom, and the engine was electric start, had an alternator etc. and was reliable, but it still just didn't match an inboard for performance or convenience. The first day out repowered with the A4 found me heading straight into 20+ knots and a nice Chesapeake chop. My crew member, who had sailed quite a bit with the outboard present, agreed that the inboard was fantastic. We were making good headway and the security was much improved. There was no comparison to the outboard and the prop pulling out of the water as we were getting bounced around. Everything about the motoring experience was improved. I would not worry about exploding with the A4. How many times do you hear of your neighbor's power boat exploding? The only ones I can think of were smoking at a fuel dock. Run your blower and you'll be just fine, and of note, if you have something like stove alcohol on board, gasoline for an outboard with a below deck tank etc., you are at risk of having explosive fumes, so run your blower anyway. Sometimes I think that when Westerbeke bought Universal, they started the campaign of FUD bashing gas inboards to increase their diesel sales...
- In any event, the A4 is a solid little engine, and with minimal maintenance, a great little power plant. Fix the strut. It should be done anyway for hull integrity, and I think you'll find you have a much better solution in the long run. If you really want to get rid of the A4, I'll take it off your hands
Final thoughts - a small outboard is just that, and will just leave you in a situation that can be dangerous when the weather kicks up and you can't push through the sea, and a good outboard is not cheap - you might be surprised how expensive it gets to do an outboard right, and then you could have just fixed the strut.