How to brace transom

[sogafishin]

I have a 14ft 48" wide V hull aluminum boat that I want to brace the transom .The motor I plan on using is a 1968 20hp Johnson.I nthink it weighs in about 85lbs.This boat and motor combo should be e great light weight combn the test run the transom would twist a little during hole shot other than that the boat handled it great.The only wood in the transom is a 2x6 up top.Would a peice of plywood added to the rear of the transom help my problem or do I need to start looking into a metal brace on the inside of the boat?Any ideas would be great. Thanks



https://i139.photobucket.com/albums/q297/kevinsauto/DSC00233.jpg



https://i139.photobucket.com/albums/q297/kevinsauto/DSC00234.jpg

 

[lckstckn2smknbrls]

There looks to be some cracks in the 2x6. I would glue and screw an oak 1x6 on top of what you have now.

 

[CatBasser]

My 1636 flat bottom has a metal brace from the floor to the transom, it was built with it, and the transom board was a 1" piece of plywood, but I have to replace it. I also have a '68 20 Hp Johnson, I haven't run it yet but my dad used to when he owned the boat, and the transom never had any problems with twisting. I remember that boat would scoot with that Johnson on it and I can't wait to get my boat done to get it back out on the water.

 

[Macgyver]

Looks like someone did a "presidential solution" on that transom at some point in it's life. I wouldn't put anything more than a trolling motor on it. if your dead set on putting that motor on it , rebuild it properly and add a brace in the middle.

 

[ben2go]

Remove the Z channel that is holding the bottom of the transom wood.Then replace the wood with a longer piece the same thickness.You will want the wood the come down and stop roughly 3 inches from the bottom of the boat.This will keep the grain from setting in any water that gets in the boat.I would also put a wood transom plate on the outside of the transom.I would make it 8 inches wide by 10 inches long.Seal the wood with a quality water sealer such as Thompsons.Us stainless steel hardware to mount the new transom.Bed the hardware in with 3M 5200 marine sealant.Seal around the wood plate with it as well.Look through the mods section to get an idea of how this looks and you will get ideas on how to do it.

 

[Cheeseball]

I agree with Ben2Go you need a wider transom board. You could also add storage boxes or deck the whole thing. The structure will give your transom a little more strength.

 

[sogafishin]

Thanks for the replies.Im am going to do what Ben2go suggested and take out the old board and Z channel and replace it with 2 sheets of 3/4" plywood then put a peice of 1/2" on the back.I already have it torn down.Hopefully I can grind the rivets off the channel today if I can stand thid 100 degree weather we are having down here.Ill try her after IM done and see if she will need anymore bracing Thanks

 

[cjldad]

Don't do what I did.. Measure the area where your outboard will clamp to the transom.. Mine is so tight, I cannot remove it easily.. But I think I used 3 plys of 3/4".. Two inside, one outside.. It is stout.. No moving at all.. And I used to be able to watch it bounce around when trailering.. Wasn't a happy thought in the back of my mind..

 

[ben2go]

Good advice.Check the transom clamp on the motor and measure how wide it will open up.Make sure you have about and 1/8 inch more inside the clamp.

 

[Macgyver]

I would add a diagonal brace like the one in the picture of my boat below. this is a 16' lowe line semi v rated for 30 HP.