Engine mounting position

Ed Bukala

Well-Known Member
Joined
May 11, 2009
Messages
66
Reaction score
0
Points
0
Hi There
Well we have just finished our first season with our Freedom 255 and for the most part it was a good one. Typical learning curve going from a 18 foot (185) to a 25 footer with hardtop. Our 300 hp is mounted in the second hole from the bottom, with two holes above. What would be the advantage of lowering the engine down one additional hole? I have a specific reason for asking this question and hope that your feedback will confirm or dismiss my thoughts on what this will do for bow behaviour.
Bukster
 

VeroWing

GreatGrady Captain
Joined
May 21, 2009
Messages
430
Reaction score
22
Points
18
Location
Vero Beach, Fl.
"Rule of thumb" relating to engine placement on transom is that the cavitation plate(flat section directly over prop) should be level to 1" higher than hull bottom directly in front of it. If engine is on a bracket or mount extending back away from transom, cavitation plate should go up 1" for each 1' back. Remember, this is only a general "rule of thumb", and some will even argue that flat plate over prop isn't really called "cavitation" plate. Sometimes people will drop outdrive deeper into water hoping to get a firmer initial bite to compensate for excess weight of hardtops, etc. This will prove to be inefficient because of the extra drag created by outdrive.
 

Parthery

GreatGrady Captain
Joined
Jan 31, 2005
Messages
2,589
Reaction score
220
Points
63
Location
Atlanta, GA
I wouldn't drop it....you will use more fuel, experience a lower top end, and increase the drag.

Are you experiencing a bow rise when you plane out? Can it be controlled by trimming the motor all the way down?
 

Ed Bukala

Well-Known Member
Joined
May 11, 2009
Messages
66
Reaction score
0
Points
0
Hi All
With the engine mounted where they have it, she gets up on plane in a flash. I do not have serious bow rise when getting up on plane, she handles great. So why am I asking this question?, well the problem is when we are travelling at low speeds as in no wake jones and have a few people enjoying the ride sitting in the bow, if there is a chop, not a big one, they often get wet. The bow seems to squat a great deal, never when on plane, just slow speeds. When on plane, people can ride up front and typically not get wet, unless there are some heavy seas but I generally do not like people up there in those conditions.
Bukster