Do I have the right Outboard shaft length?

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timschap

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Aug 13, 2015
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My apologizes if this is the wrong place to ask this question. I have a 1995 Grady White Islander (26.8). It has a 2004 Merc 225 with a 30" shaft. I'm confused whether this is the right length or to long. The boat struggle to get on plane. The transom is 21". However the keel is 28" forward of the transom (swim platform where OB is mounted). Running a straight edge from keel to the cavitation plate the plate is about 1' higher. So do I lower the engine 1" (which I can do as it is mounted in the bottom holes) or raise it 10" (remove the OB shaft extension)? Thanks Tom
 
Q

QBhoy

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I’m not 100% clear on getting a picture of what you have but if I have it right...and the keel is way forward of the transom water line...the engine should be set to the transom and not the keel.
Dont know the boat at all though.
You AV plate should be set about 1-3” above the line of the planing rear most part of the hull usually. 30” is an XL shaft last I looked. Strange you have a 20” transom.
 
dingbat

dingbat

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Nov 20, 2001
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That boat takes a 30” shaft with single, 25” shaft with twins

The boat is under powered at 225hp.

You could get the boat OEM with a single 250hp, but most where sold with twin 175s or 200s
 
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timschap

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Aug 13, 2015
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O'bhoy, yes the keel is 28" forward of the transom. Dingbat, I have seen a couple of Grady Whites 27 with a single 250 that were advertised as a original but they didn't say how long the shaft was so I thinking that the 225 is under powered. I was thinking of getting a used 300hp but still need to know how long the shaft should be. By the sounds of it I'm looking for a 30" shaft. Please feel free to correct me ...
 
dingbat

dingbat

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timschap said:
O'bhoy, yes the keel is 28" forward of the transom. Dingbat, I have seen a couple of Grady Whites 27 with a single 250 that were advertised as a original but they didn't say how long the shaft was so I thinking that the 225 is under powered. I was thinking of getting a used 300hp but still need to know how long the shaft should be. By the sounds of it I'm looking for a 30" shaft. Please feel free to correct me ...
Click to expand...
A good friend Has your boat with twin 200’s. Can’t imagine a single 225

As I said earlier....30” shaft for single outboard, 25” shafts for twins
 
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