What's different between 7.5 long and short shaft?

Bearcamp

Petty Officer 1st Class
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May 21, 2003
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341
What is different between a short shaft and a long shaft Mercury? Is it the drive shaft, shift rod and threaded stud? Or is there more than I talking about? In other words, can I use the long on my short?
 

wilde1j

Vice Admiral
Joined
Apr 15, 2002
Messages
5,964
Re: What's different between 7.5 long and short shaft?

Short shaft measures 15" from cavitation plate to where mounting bracket sits on transom. Long shaft is 20". Not sure what you're asking, but they are not interchangeable (the boat determines which is to be used).
 

Bearcamp

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Re: What's different between 7.5 long and short shaft?

But is the lower unit the same? Is the extra lenght for the long shaft in the mid section?
 

emckelvy

Commander
Joined
Jan 16, 2004
Messages
2,506
Re: What's different between 7.5 long and short shaft?

You would have to change out the driveshafts in order to use a longshaft lower unit on a short shaft motor. If this is an older 7.5, the lower unit must come apart in order to get the driveshaft out. Also, it's possible that the shift shaft lengths will be different. Shift shafts can fairly easily be changed, but if you don't do it right you can mess that up too. Of course if you're dismantling the lower unit to change shafts, it's a piece of cake to change out the shift shaft at that time.<br /><br />HTH.........ed
 

Bearcamp

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Re: What's different between 7.5 long and short shaft?

That's just what I needed to know, Thanks.
 
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