Patching outdrives with Bondo?
 

I have two holes in each cavitation plate from a previous drive shower installation. I want to plug these holes withe something. What about just bondo-ing these up and prime and paint. Any problems with that?

Probably not, but bondo was not meant to span any distance, i.e., holes. I have been told that it will also absorb water if the paint got a nick and expand. Sea-goin epoxy works like bondo, but hardens more. Can be primed and painted the same. WPM can source it among others.

I'd suggest you clamp something like a paint stir stick on the bottom of the cavitation plate to block the hole, then force fill it with JB weld or MarineTex two part epoxy. Both are water resistant and will adhere to metal. Bondo will absorb water and expand.

Thanks I have some JB at home I'll try that. :)

I have not been satisfied with MarineTex. My problems have been lack of adhesion to it's self, pockets that did not set, and slow cure times. I have never had a negative experience with JB weld or any of the other "plumbers putties". I'd try that. Don't forget that you'll need to repaint so grab that can of Phantom Black before you start.

Make sure the sides of the hole are clean aluminum and not oxidized. You might want to clean them with a dremel or a round file. I think the jb weld will work too.

You could just weld them up.. If you don't have a welder take it to a guy they might charge you $20 to do it.

I thought about welding them but I only have a mig welder. I dont think it does aluminum. I am also concerned about heating the case too much with out dissassembly. I was told once by a repair guy this was bad.

Ray, you have two options. 1) use J.B> weld. or @) weld it -- agood welder won't get it hot enough to do any damsge to the seals.

Randy

if you cannot find a decent welder use VC watertite, can be used up to 3/4's of an inch and is the s#!t, my .02 cents.

MarineTex. I built a whole skeg out of it once. Held up as good as the original..

Countersink both sides of the holes before filling them. The countersink will keep the filler from possibly falling out.

Bondo will not work. It would be a temporary fix at best. Have some one weld them up it is not going to be expensive at all and will be permanent. :D :D

Jon

Been there done just that! JB Weld worked just as good as new. That was 3 years ago.

I went to get some JB Weld and I saw another product. PC-Metal by PCProcucts http://www.pcepoxy.com It is a putty type epoxy. I just kneeded it up and plugged the holes. It hardens in like 5 minutes. You can sand after 30 min. (The JB weld takes up to 15 Hours to set up!) The PC Metal is also waterproof or so it says. I sanded it down and it looks great! Now to prime an paint.

I used marine Tex on my nose cones. worked better than any thing else

When welding is to be done on an outdrive , it must be heliarc (TIG) welded. Aluminum can be easily welded with aluminum mig wire and pure argon, But the weld will be too soft and will not stand up to electrolysis and corrosion in a marine environment.Aluminum also can be gas welded but is a poor choice do to excess heat/ distortion. My 2 cents,
Big Block Billy :)

ttt

Bondo used under water does not hold up. Over the course of a season it absorbes water and becomes less hard. It is a little hard to describe but I have used it for I/O repair and would not do it again. Try one of the other epoxy fillers.

Doug

Ive used both epoxy and bondo. Epoxy doesnt shrink and I think it works better. Niether have come off. Greg