Swapping motors

[BOAH]

I've got a 21' starcraft and I'm going to be taking off the '73 Evinrude 115 and installing a '98 Yamaha 115. I've never swapped motors on a boat like this before. Are there any writeups on how to do this, how to seal it, bolts to use, etc?

Thanks for your help!

 

[metriccrescentwrench]

Re: Swapping motors

I use 1/2" fine thread stainless steel bolts with nylock nuts (I get hardware like that from bolt depot). I use anti-seize on the bolts so the nuts can't gall which would require cutting the bolts the next time you need to remove them (don't use the type of anti-seize with copper in it). Also use the largest stainless washers you can find on the inside of the transom to spread the load. And do a very good job of sealing up the bolt holes using 3M 5200, you don't want to let one single solitary drop of water reach the wood in your transom.

 

[durban]

Re: Swapping motors

wot i do if the transom is for example 45mm thick i get a nylon tube with the inside diameter of the tube to fit neatly over the bolt , then drill the hole according to the outside diameter of the tube then cut the tube to 35mm in length , this tube then gets epoxied in to the transom with 5mm either side gap these gaps gets epoxied , the results leave me with a hole in the transom that is completely sealed off & no water gets in to the transom , prevents wood rot over years to come , this method mainly apply,s to the 2 holes near the water line :joyous:

 

[bonzoscott]

Re: Swapping motors

You may want to poke around on the "Restoration" page. It sounds a bit over kill but doable. A properly sealed transom shouldn't need the tube and what not. There are some super duty 3M products for marine applications. Like I said, stroll through the restoration page and you'll get all you need to know.