transom extension and trailer bunk redo

[handyandy]

New to the forum and thought I'd comment. Nice project! I've been keeping my eyes open for something of this nature. I'm still looking for a jet pump to fit my 90 horse 2000 Johnson that won't break the bank. It's a long shaft motor so I'll eventually need to do this mod. I do have a question though. How did you go about closing up the holes in the transom? Mine has wood sandwiched between the aluminum sheets on the inside and outside. I'm kind of reluctant to weld them shut with the possibility of catching the wood on fire. That would not be good! Also, mine has a cap that covers the wood and I don't think it would be sufficient to weld to so I'll probably straddle it and weld to the inner and outer sheets when I do it. Any advice is appreciated. One other item I'll have to address is the extra weight of the Johnson engine. I have a four stroke 40 Yamaha on it now and the Johnson will add over 100 lbs. of weight so pods will probably be in order.

With that type of transom with wood your probably in for a transom redo and making it entirely out of aluminum. My boats transom was all aluminum made from boxed tubing and .125 sheet over it from the factory. So I did just weld up the holes. The holes were a pain to weld had to use my tig welder and no matter how clean I got the metal while welding once I got a little pool of melted aluminum to start and try and close the wholes up crap from the back side of the aluminum would manage to get into my weld puddle. Making me have to stop a lot grind and wire wheel it more to clean it up of the contaminates weld a little more repeat to I had it closed up. What sort of hull are you working on? Where are you located?

 

[CedarRiverScooter]

I would pack the wood holes with fiberglass & resin, then put some 3M5200 over that for good luck.