MerCruiser alpha 1 gen 2 tapping noise in lower half

baily29

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Apr 30, 2009
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This drive has about 600 hours on it. I didn't have enough load on the throttle, and the engine was at a higher RPM than normal. In a panic I jammed the drive into forward gear. Since then the drive has a metallic tapping noise in forward gear (can't hear it in reverse. Thought maybe I stretched the cable, but adjustments make no difference. Cracked the drive in half. I notice when i spin the prop by hand the vertical center shaft has a little 'pop' at one point in the rotation. Is this pop normal? You can clearly see and hear the pop in the following video.
 

alldodge

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Mar 8, 2009
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Welcome

Most likely broke a tooth
Pull the prop shaft and have a look
 

Bt Doctur

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Aug 29, 2004
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19,343
its the gen II type, to properly do what your doing and to preload the gears turn the unit upside down. those gearsets force the pinion upwards or use the tool to keep the driveshaft raised up by spring pressure.
 

baily29

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Apr 30, 2009
Messages
3
Welcome

Most likely broke a tooth
Pull the prop shaft and have a look
Thanks for the reply, that was my guess. I did have a heck of a lot of metal filings on the magnet when I drained the lube. From memory whenever I did my impeller I believe that shaft moved pretty smooth.
 

Scott06

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Apr 20, 2014
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Thanks for the reply, that was my guess. I did have a heck of a lot of metal filings on the magnet when I drained the lube. From memory whenever I did my impeller I believe that shaft moved pretty smooth.
if you don't have it get a factory manual for your drive as it outlines in detail all the procedures to set it up correctly. Also be aware that you will need some Mercruiser specific tools for this job in addition to some decent mechanics tools.

When I did mine I was able to find the Merc tools on ebay used for about half price. Even if the issue is in just one half of the drive would recommend disassembling and cleaning all the parts as metal will get throughout the drive
 

baily29

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Apr 30, 2009
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if you don't have it get a factory manual for your drive as it outlines in detail all the procedures to set it up correctly. Also be aware that you will need some Mercruiser specific tools for this job in addition to some decent mechanics tools.

When I did mine I was able to find the Merc tools on ebay used for about half price. Even if the issue is in just one half of the drive would recommend disassembling and cleaning all the parts as metal will get throughout the drive
Thanks. By the time I get the parts, learn what I'm doing or have a mechanic repair it, I might as well spend 2800 on a brand new quicksilver drive. I plan on keeping boat. I still may take it apart eventually just out of curiosity. The top half is probably worth something to somebody.
 

Scott06

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Joined
Apr 20, 2014
Messages
6,722
Thanks. By the time I get the parts, learn what I'm doing or have a mechanic repair it, I might as well spend 2800 on a brand new quicksilver drive. I plan on keeping boat. I still may take it apart eventually just out of curiosity. The top half is probably worth something to somebody.
That is not a bad route if you like the boat.

OEM is always best but -not sure the age of the boat a lot of folks will look at SEI Drives which are a good aftermarket replacement with a 3 yr warranty if you want to save a few bucks.
 
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