Trailer Rusting all of a sudden

[fairpilot]

My trailer which is 11 yrs old just started rusting in a weird spot, this area never touches salt water, it started as a small spot which I ground off and filled with JB weld, then it came back and was oozing some form of liquid from it, it has now grown to this (my fault it got this bad) still oozing liquid. Today i ground it off and took some pics, looking for best way to repair. I know that trailer replacement is in my future, but would like to get some more time out of it if possible. My concern is structural, as you see it is being eaten alive.

Note the water you see dripping is from dew this morning. Also this is the only place doing this and it is only about 6 ft from hitch so does not get water inside this area

 

[Murf'n'surf]

I’m thinking that salt water gets up there after your launch/retrieval by gravity. When you pull out, there’s a small amount of water in the channel, aft of the rusting spot. Your trailer may sit a little out of level and the water rolls to this spot in front. This might happen while you store it as well.

Maybe you can sister up some supports to add a little strength to get a few more worry free years?

 

[fairpilot]

Yeah I was thinking a weld shop but when it's all done it will prob look like a rig job. Going to ospho it then patch and apply zinc spray and see what happens.

 

[Matt Phillips]

I agree with @fairpilot, you're likely getting some salt water in there when backing into the water (it probably rolls up inside the frame like waves on a beach). that's a pretty integral part of the trailer and I'd be worried about structural integrity if it rusts too much. I'm not sure how to fix it...other than maybe time to replace the trailer? 11 years being dunked in salt water is a pretty long time...especially for the 'quality' trailers Yamaha specifies for our boats.

 

[fairpilot]

Very odd this spot doesn't go in water and rest of trailer that gets submerged has zero rust. Our ramp is very steep we always pull out enough to drain trailer. I do agree though that water could creep there after we park but don't understand why it not rusting on bottom of this area where any water would sit. It 1-2 inches up rail.

 

[McMark]

Galvanizing is sacrificial. Over time this is what happens.

 

[njmr2fan]

I wonder if this would help?

Corroseal Water-Based Rust Converter
by Corroseal
Link: http://a.co/5FTB4Bv

 

[Ronnie]

Reminds me of a post from one of the members here that lives in Thailand where he included pics of trailers that broke in half at about the same point due to rusting from the inside out. Maybe I’m just paranoid but I would be concerned enough to take it to a shop for them to check it out and possibly weld some support plates on both sides of the trailer in an effort to prolong the trailer’s remaining useful life. If it looks like that on the outside it may look a lot worse on the inside.

 

[Bruce]

Fluid Film might help to protect the remaining metal.

I also worry about the strength of the remaining metal.