Hi guys. One of your members suggested that I poke my head in here to ask my question about helping a buddy who made the misguided error of buying a boat with a 3.7 liter Merc. with Alpha drive. That motor is in need of serious repair or replacement, and I'm trying to help him out. I've owned only outboards and Volvo stern drives, so I'm not well versed on the ins and outs of mercruiser. So here I am.
First and foremost, theres a guy right down a road with a boat my friend can buy for very little money. This boat has the 120 merc and older style outdrive. The one with the lifting ring cast into the cap. Is that drive a straight swap with the Alpha? IE: Could we pick up that boat, make whatever motor mount mods are needed to get the engine fitted to my friends boat, then mount up the drive?
Or, I can put some time in to try to find another engine. 3.0 or 4.3, but as I understand it, the 4.3 is compatible with the 3.7 Alpha due to gear ratio, but is not as easy to bolt up due to greater difference in engine mounts? The boat is a 88 Raven cuddy, which was available with the 4.3 as I understand, so maybe the mounts will be there?
Any guidance or suggestions would be welcome. (Yes, I know his best bet would be to sell the boat and start with a boat with a better power plant, but that option is off the table)
Edit: Original problem that lead up to all this is #4 cylinder being full of coolant. Haven't investigated why yet, but I haven't found many people who recommend repair the 3.7 vs replacing. If you gents want to talk me into repair, I'm all ears.
First and foremost, theres a guy right down a road with a boat my friend can buy for very little money. This boat has the 120 merc and older style outdrive. The one with the lifting ring cast into the cap. Is that drive a straight swap with the Alpha? IE: Could we pick up that boat, make whatever motor mount mods are needed to get the engine fitted to my friends boat, then mount up the drive?
Or, I can put some time in to try to find another engine. 3.0 or 4.3, but as I understand it, the 4.3 is compatible with the 3.7 Alpha due to gear ratio, but is not as easy to bolt up due to greater difference in engine mounts? The boat is a 88 Raven cuddy, which was available with the 4.3 as I understand, so maybe the mounts will be there?
Any guidance or suggestions would be welcome. (Yes, I know his best bet would be to sell the boat and start with a boat with a better power plant, but that option is off the table)
Edit: Original problem that lead up to all this is #4 cylinder being full of coolant. Haven't investigated why yet, but I haven't found many people who recommend repair the 3.7 vs replacing. If you gents want to talk me into repair, I'm all ears.
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