25 inch shaft

[joe priddy]

I recently purchased a 16' Starcraft boat with a 9.8 mercury motor long shaft. I decided to upgrade to a 25 hp johnson long shaft. Found one in good condition, 1971 model, owner started it for me and everything seemed ok.
Several days later I got the chance to try it out. It started fine and took me out of the no wake zone. When I gave it full throttle it surged terribly. It sounded like the prop was coming out of the water. I took it to the marina and said he'd get to it in a few days. In the meantime I started researching shaft lengths. I was under the impression the there were 2 lengths, 15 and 20inch. I soon dicovered that there is also a 25 and 30 inch. This morning my mechanic calls to say there's nothing wrong with the motor, but the shaft is too short, I need a 25 inch. They don't make kit extensions for that year motor. I don't know where to start looking for a similar motor that I can salvage the longer shaft from . Any ideas??

 

[Bob_VT]

Re: 25 inch shaft

What model Starcraft do you have?? 95% of them (maybe higher) in the 16' length all used a 20" shaft.

Got pictures? This just sounds strange to me...... my 16' Starcraft has a 20" shaft transom.

Measure from the top of the transom to the bottom of the keel (Straight down) and let us know.

Welcome to iboats..... be sure to check out the Starcraft section we have on iboats (very active)

 

[joe priddy]

Re: 25 inch shaft

The distance from the top of transom to the bottom of the keel is 21". The motor I bought was listed as a long shaft. The distance from the top of transom to the cavitation plate is 18". I assumed it would be 20". So my cavitation plate almost sticks out of the water even with me standing there.
So when I give it full throttle only half the prop is in the water.