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the real honcho
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Discussion Starter #1
I have an 83 omega i/o 305 rated @ 220hp with a alpha one drive. I blew my drive over fathersday weekend. How do I know what gear ratio I have? Any help would be great.
 

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On the port side of the upper drive where the Mercruiser decal is, there is a serial # as well as the gear ratio stamped into that sticker. It's about 6" to 7" below the top of the outdrive.
 

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FWIW,

You should have a 1.65:1 gear ratio...;)

GT
 

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It's what we do
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If you can't read the ratio on the outside you can count the teeth in the upper housing.
It would be very rare if they were not one of the ones listed below.

1.65 = 24/24
1.50 = 20/22
1.84 = 17/19
 

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the real honcho
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Discussion Starter #6
Thanks for the help again... couldn't read the serial number and half of my teeth on the gears are gone. But pretty sure its the 1.65to1. What are the chances the lower unit is bad? Haven't torn it apart yet. But having all the pieces of metal running through the drive can't be good.
 

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It's what we do
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It's bad. Bearings for sure and the gears are 27 years old....

You should still be able to count the gear teeth.
 
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