torn weld repairs?

[cerevisiaephilus]

I have a 16'x56" flat bottom welded jon (Weldbilt) with a Yamaha 60/40 tiller. Purchased new in 2014. You guys were really helpful when I was looking for the boat and when I had some issues with overheating when the boat was new.

I was doing some service on the trailer and noticed a pretty bad torn weld on the brace that holds the transom to the floor. It appears the transom is pulling back and tearing the weld. I've had it out a few times this fall and hadn't noticed this until today. Not sure when it happened.

What do you guys think about a repair here? Pretty critical structure in the boat. Maybe the 60/40 is just too big for the transom?

Not sure why the photos are rotated, but you can orient yourself to the top edge of the transom.

 

[CedarRiverScooter]

Definitely poor weld quality. A weld shop can grind out the bad weld, reweld it & then put a doubler plate on top (both sides) & weld that down too. If you really want belt & suspenders strength you could also thru-bolt.

 

[nccatfisher]

I am going to go against the flow here. The weld did it's job here. The base metal tore, common thing with aluminum. It was stressed to it's limits. Yes, it can be fixed, but whatever caused it be it impact or otherwise may do it again.

 

[onthewater102]

I'm with nccatfisher - that's the plate of the transom that cracked, not the weld.

No way to tell whether it was caused by running in heavy chop too often, hanging too heavy a motor or hanging the motor with too much setback to where it applied too much torque, but one way or the other the top of the transom was pulled straight backwards by a load to cause that.

That's the type of stress a transom saver is intended to help alleviate, I would certainly add one to the trailer if you don't have one already to help avoid a re-occurrence.

 

[nccatfisher]

Yep, I do a bunch of aluminum repair. Trailering accounts for many of those braces looking just like that. Especially with a motor with a high set or a transom that has been extended for a long shaft motor.

 

[cerevisiaephilus]

Thanks, guys. I arrived at the same conclusion: 270lb Yamaha jet on a short transom with a CMC lift adapter which puts it pretty high, no transom saver (not sure how they work with a jet anyway), and 5 years of trailering on bad roads. A friend fixed it the other day. Not pretty, but beefy, and he said it should hold "until next time" hahahahaha. He did it in less than an hour for free. Hopefully I get a few more years out of it. Should probably re-engineer the whole junction between the knee brace and transom - grind down the welds, add some plates to the seams, weld those and bolt through as CedarRiverScooter suggests.

 

[JL8Jeff]

I've seen so many of those Yamaha 60/40 jets mounted on the CMC plate really high like that. I'm surprised so many dealers install those long motors on short transom boats without building up the transom.

 

[Alphawolf]

Not sure why the photos are rotated, but you can orient yourself to the top edge of the transom.

Because they were taken with an iPhone 8 which set the orientation of the pictures to rotate 90 degrees. this post explains it in more detail.

 

[maintenanceguy]

I took all of the weight off of the knee brace on my boat. I added a piece of rectangular tube behind the rear bench seat and used two pieces of 3/8 threaded rod to anchor the transom to that tube. My knee brace showed some cracking at the floor of the boat so I wanted something that I didn't have to worry would crack again. The transom is rock solid and there is no stress on the knee brace. The photo below is in the middle of a painting job.