Patching old screw holes in aluminum hull

Discussion in 'Boat Tips' started by Chrisingeorgia, May 16, 2007.

  1. Chrisingeorgia

    Chrisingeorgia New Member

    Messages:
    113
    State:
    NY
    I bought a used tracker aluminum boat a couple weeks ago and need some tips on sealing some old screw holes. The previous owner removed his fish finder transducer before selling the boat and left the brackets behind. Problem is my transducer needs to be mounted in the same location, but doesn't match up with the holes on the old bracket, so I'm going to need to drill new mounting holes. Would it be possible to seal them using a mapp gas torch and brazing rods? I don't own a welding machine or an oxyacetylene torch.
     
  2. GMC FishHauler

    GMC FishHauler New Member

    Messages:
    1,335
    State:
    Waco, Texas, Un
    why not just fill them with marine calk or silicone. if the holes are alot bigger than u would like, put an oldscrew in them with silicone over and under it.
     

  3. Chrisingeorgia

    Chrisingeorgia New Member

    Messages:
    113
    State:
    NY
    I was just hoping for a more permanent solution that I wouldn't have to worry about leaking in the future. I already have the holes caulked with silicone, but I wasn't able to run the screws back into them because the holes are underneith the new mounting bracket which is slightly larger than the old one. Caulk will have to work for now.
     
  4. KansasKatter

    KansasKatter New Member

    Messages:
    807
    State:
    Wichita Kansas
    If it were me, I would take the easy route and just coat some screws (aluminum or stainless) with some good marine silicone and put the screw in the old holes and leave them in. That will seal the holes as good as anything, and you never know, you may be able to use them again someday. This of course is only if your new bracket will clear the heads of the screws.
     
  5. last chance

    last chance New Member

    Messages:
    56
    State:
    Louisiana
    I've used JB Weld to patch holes in aluminum several times over the years and it has done very good. You could also use silicone caulk. I bought 21/2 lbs. of those aluminum brazing rods and it would take a lot of practice before I would give those a try on my boat and I've been welding for about 40 yrs. Good luck and let us know how it comes out.
     
  6. Catter

    Catter New Member

    Messages:
    181
    State:
    Osceola, Arkansas
    I used some of the aluminum rods to weld up some holes on our boat. It was alot easier than I thought it would be, just make sure to use a stainless brush and clean the area very well before you start.

    Joe
     
  7. riddleofsteel

    riddleofsteel New Member

    Messages:
    353
    State:
    NC
    Degrease and sand the area down inside and out. Select a stainless screw that will tap into the hole. Mix up some marine epoxy and coat the screw threads. Insert the screws and when tight go inside the hull and put some epoxy on the threads exposed on the inside.

    It will be stronger than the boat.
     
  8. kickin_wing

    kickin_wing New Member

    Messages:
    324
    State:
    Illinois
    I used silicone in the old screw holes in my boat just so in the winter when water happens to freeze in them it wont expand.
     
  9. fwmud

    fwmud New Member

    Messages:
    693
    State:
    Wilson's Mills,nc
    chris, the "rods" are made by "Dura-fix". You can buy them off the web. They would be the only permament fix. The "weld" is accually stronger than the aluminum its self.
    The kit comes with a stainless steel brush to clean/prepare the area. Like was already said, practice on some scrap metal first before trying it on your boat.All you need is the kit and a common plumbers tourch.(Mapp or propane)
     
  10. moriver

    moriver New Member

    Messages:
    416
    State:
    Missouri
    Chris

    Give this some though. If you take a look at big water boats that run multiple transducers they sometimes have what boils do to be a piece of plastic that is 1/2 in thick X two inches tall X ten inches long. attached to the back of the boat that all the transducers fasten to. That way they dont have to keep putting holes in the back of the boat. Plus that plasic holds a screw better than sheet aluminum does. You could find that piece they use or come up with someting on your own and put it on the back of the boat over the old holes with some silicone and you would be good to go.:wink:
     
  11. Katmandeux

    Katmandeux New Member

    Messages:
    1,618
    State:
    Checotah, Oklahoma
    I would take the boat to someone who knows what they're doing, and get it repaired correctly. Once.
     
  12. Catter

    Catter New Member

    Messages:
    181
    State:
    Osceola, Arkansas
    Just to expand on what Moriver said, you can use a piece of a plastic cutting board from wallyworld for mounting the transducer to. Just use 5200 behind it with 4 screws in the corners then you can screw your transducer to it, makes it alot easier to adjust too.

    Joe
     
  13. Koon

    Koon New Member

    Messages:
    167
    State:
    Oklahoma
    walmart sell a marine epoxy stick in the automotive section... stuff is like JBweld but can be used under water if needed.

    Easy to use, cheap (under 5 bucks) and ROCK SOLID.
     
  14. Chrisingeorgia

    Chrisingeorgia New Member

    Messages:
    113
    State:
    NY
    I like that idea with the plastic cutting board. Sure beats turning my transom into swiss cheese. What's 5200? Some kind of gasket?
     
  15. Mark J

    Mark J New Member

    Messages:
    9,407
    State:
    Four Oaks, NC
    5200 is a marine sealent that comes in caulk size tubes and small squeeze tubes.
    You put it there, its there.
    It doesnt mold or mildew.
     
  16. Chrisingeorgia

    Chrisingeorgia New Member

    Messages:
    113
    State:
    NY
    Thanks Mark. I'm going to pick some up and give it a try. By the way, I tried using some of those brazing rods on a piece of scrap aluminum and it was a lot harder than I thought it would be. I ended up with a hole that was even bigger than the one I started with. Don't think I'll be using those on my boat anytime soon. Thanks for all the great ideas guys.