Moderated Discussion Areas
  ContinuousWave: Whaler Repairs/Mods
  Outboard swap, transom profile, bracket shape

Post New Topic  Post Reply
search | FAQ | profile | register | author help

Author Topic:   Outboard swap, transom profile, bracket shape
DanT posted 11-27-2001 06:19 PM ET (US)   Profile for DanT   Send Email to DanT  
I have a 1966 Eastport. Time has come to retire the original 1966 100hp Evinrude. I found a used 90hp Yamaha that I would like to use. The transom has a slight curve to it. The old Evinrude had a two piece bracket that bolted tightly to the transom. The Yamaha bracket is one piece and flat. I haven't put the Yamaha on the boat yet but I think the bracket won't lay flat against the transon due to the slight curvature of the transom. The mounting holes should line up but I am concerned about the correct way to attach the bracket. Should a shim of some sort be used? Also, does anyone know the thread size of the blind mounting holes on the Yamaha? Thanks Dan
Wayneman posted 11-27-2001 07:21 PM ET (US)     Profile for Wayneman  Send Email to Wayneman     
Hello DanT,

What are you going to do with your old Evinrude 100? Is it worth rebuilding? I might be interested.
Bigshot posted 11-28-2001 09:58 AM ET (US)     Profile for Bigshot  Send Email to Bigshot     
What blind mounting holes?
DanT posted 11-28-2001 03:46 PM ET (US)     Profile for DanT  Send Email to DanT     
The blind holes (I think that's what they are called) are the lower holes in the Yamaha bracket that will match up with the lower holes in the splash well. They are threaded but dont pass all the way through the bracket. The bolt would be inserted from the splash well and threaded into the bracket. This hole is not visible from outside. Thanks, Dan
DanT posted 11-28-2001 03:56 PM ET (US)     Profile for DanT  Send Email to DanT     
I haven't decided what I'm going to do with the old Evinrude. It does run but it needs some maintenance. If you're interested and would like to make an offer I'll consider it. If you want more information on the motor send me an Email. Dan
Bigshot posted 11-28-2001 04:20 PM ET (US)     Profile for Bigshot  Send Email to Bigshot     
Mine has a slot that the bolt goes through. When you look at the back of my 90 Yamaha you see 4 bolts. All engines are that way. Double check. That blind thing is for something else I believe.
DanT posted 11-28-2001 05:12 PM ET (US)     Profile for DanT  Send Email to DanT     
I checked the motor and transom again. The bracket has four holes near the top, one blind hole and then a slot below the blind hole. The hole pattern in the transom from the old Evinrude matches perfectly with the top two holes and the blind holes. If I were to use the slots they will fall below the splash well and a lag screw would be needed. If the motor was raised to allow access to the slots from the splash well I would still need to redrill the transom because the distanse between the slots is less than the distance between the blind holes. What I'm really interested in is how to deal with the slight curvature of the transom when using a bracket that is straight. Dan
Clark Roberts posted 11-28-2001 05:41 PM ET (US)     Profile for Clark Roberts  Send Email to Clark Roberts     
Some of the early Montauks had very shallow splash wells and it was not possible to use the two lower bolt holes (or lower slots) and the blind (threaded) holes were necessary. Most engines have these blind holes... great if you need them but there is no height adjustment once transom is drilled! Clark
Bigshot posted 11-29-2001 10:39 AM ET (US)     Profile for Bigshot  Send Email to Bigshot     
Learn something new everyday!
gunnelgrabber posted 11-29-2001 04:17 PM ET (US)     Profile for gunnelgrabber  Send Email to gunnelgrabber     
it's mostly an omc "thing" , maybe? when i got my old used katama it was "one hole up",blind holes drilled for it.i thought the engine ,( for different reasons) was supposed to have the cav plate flush with boat i lowered it one hole (all the way down)...after reading clark and others recommending "go at least one hole up"..i returned.. and as clark just said...2 pr. of blind holes now.filled the extras. wow! does it go good! and feels like power steering!haven't checked gps yet ,but the seat of the pants perception is a significant difference!! learned it all right here. thanks..lm

Post New Topic  Post Reply
Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.