Raising Outboard Mounting Height

dd716ted

Petty Officer 2nd Class
Joined
Aug 26, 2002
Messages
109
I need to raise my Honda 50 (1 mounting hole) so that the cavitation plate is even with the keel. After looking at the motor raising task, I see 3 ways to do it and need some advice. <br /><br />The problem with raising the motor is that the notch at the top of the Honda 50 motor mounting plate that neatly went over the aluminum or stainless boat transom trim would be now be above the trim and the flat part of the motor motor mount that was flush against the stern would now rest against the trim. I see three methods to overcome this problem, but am looking for advice.<br /><br />Method 1: Easiest.. Place large (2") stainless steel 1/16" fender washers on the mounting bolts between the motor mount and the stern on the top or both top and bottom motor mount bolts. This would allow for the motor mount set back to clear the trim strip.<br /><br />Method 2: Notch the metal boat trim strip to allow for the motor mount to set flush, seal with RTV.. but I see that this might impact watertight integrity.<br /><br />Method 3: Fabricate two (2 inch wide 1/16th inch thick) aluminum or stainless plates to go vertically over both the top and bottom mounting bolts between the motor and transom.
 

Old Jarhead

Petty Officer 2nd Class
Joined
Sep 26, 2003
Messages
190
Re: Raising Outboard Mounting Height

My vote is for #2 and here's why. <br /><br />You want the full area of the engine mount against the transom. Shims are used in some cases but as a rule of thumb (IMHO) not the best idea.<br /><br />Hey, just my 2¢. :)
 

Old Jarhead

Petty Officer 2nd Class
Joined
Sep 26, 2003
Messages
190
Re: Raising Outboard Mounting Height

Sorry, forgot to add. <br /><br />Seal the notched area with 3M 5200 or 4200 and forget about it...
 

quantumleap

Master Chief Petty Officer
Joined
Feb 16, 2004
Messages
813
Re: Raising Outboard Mounting Height

I'm leaning toward #2, but hate to 'notch' anything if you dont have to. How about adding a set back plate?
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,571
Re: Raising Outboard Mounting Height

Why not get a piece of aluminum the entire size of the motor's mounting area, and use it to set the motor back enough to clear the trim. You could also use solid pressure treated lumber, like a 1X8.
 
D

DJ

Guest
Re: Raising Outboard Mounting Height

#1 or #3.<br /><br />50 HP is not going to cause problems with either method.
 
Top