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Mercruiser 7.4 454 gen4 to a gen5 rebuilt block

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Mercruiser 7.4 454 gen4 to a gen5 rebuilt block

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Old 06-15-2025 | 07:43 AM
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Default Mercruiser 7.4 454 gen4 to a gen5 rebuilt block

Aloha boater brothers,here is my problem went from a gen 4 to a gen 5. I have replaced everything to gen 5,but my gen 5 flywheel is on the wrong side for my housing for starter I have the bottom starter mount and I read I can flip flywheel over and then I would have it the way it will engage in my starter ?or do I have to change my housing to gen 5 topmount and get different transom engine mounts....ect ect.thank you for helping with my confusion .Mahalo
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Old 06-15-2025 | 08:28 AM
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The flywheel only goes on 1 way
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Old 06-15-2025 | 09:06 AM
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by flipping,,they ment putting the ring gear on the other side of the flywheel.you can bang the ring gear off,,but need to heat it up enough to expand it,then it literally falls on.may have to tap it in places afterwards as it can distort a little some times
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Old 06-15-2025 | 10:24 AM
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Lots of YT vids on how to safely remove and install the ring.
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Old 06-15-2025 | 11:12 AM
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Heat the ring and tap it over with a block of wood and a hammer
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Old 06-15-2025 | 12:47 PM
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I heat the ring gears in an oven to about 450 for 30 minutes or so and they fall right on.
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