71 GMC Pontoon

Discussion in 'Boating' started by Little Mac, Jan 6, 2008.

  1. Little Mac

    Little Mac Active Member

    Messages:
    1,828
    State:
    NW Arkansa
    I picked this up in some of my swapping around, its a 71 model and has GMC on it, has a 40hp on it. I cant find any references to this boat on the internet, or this style of pontoon. Anyone out there have any information on this style, I would like to know what is in the pontoons is it filled with foam?? I will have to take it apart anyway to rebuild the pontoons as they have dents and pinholes is there a good bondo like substance to fill these holes? The deck seems to be good on it. Just needs cleaned up. Any information would be appreciated . Mac
     

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  2. biga

    biga Well-Known Member

    Messages:
    2,111
    State:
    evansville
    looks like it has potential but i have never seen anything like it...
     

  3. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Jim I don't know of any bondo that I would trust around water except Marine tex. It will hold below the water line but I would opt to weld them up. Most likely the toons aren't foam filled. You can take a rubber hammer and sound the toons to see if they are filled. I haven't heard of the GMC made toon but I will see what I can find out also. Are the toons flat on top.
     
  4. Mark J

    Mark J New Member

    Messages:
    9,407
    State:
    Four Oaks, NC
    LocTite makes a product called aluminum putty.
    Its a part A part B epoxy base system.
    Its popular among pontoon circles.

    I used some on my toons in places. Its sandable too.

    Are those toons aluminum or galvanized steel?
     
  5. ozzy

    ozzy New Member

    Messages:
    3,936
    State:
    Lost Wages
    Nice looking project cat gunner there.
     
  6. Big Sam

    Big Sam Well-Known Member

    Messages:
    4,286
    State:
    Booneville AR
    Name:
    Sam
    Definately got good potential mac....i like the turned up front, shouldn't spray ya as bad going through the water.
     
  7. BLKCLOUD

    BLKCLOUD New Member

    Messages:
    378
    State:
    Pulaski Tn
    Ive heard of them gmc boats..I think it when you work on it you had better Get More Cash :big_smile:
     
  8. Little Mac

    Little Mac Active Member

    Messages:
    1,828
    State:
    NW Arkansa
    The Toons are flat on top, and made of aluminum. I havent thought of "sounding" them, I'll try that. They do have drain bolts in the back, not plugs, bolts. I had read somewhere of a bondo or putty, just wasnt sure of the name. Thanks guys..... Get more cash, That cracks me up. LOL :smile2:
     
  9. Little Mac

    Little Mac Active Member

    Messages:
    1,828
    State:
    NW Arkansa
    Sam with a 40 on it, i doubt it will go fast enough to spray:roll_eyes::big_smile:, Now if ya tow me with that new boat of yours that might be a different story. LOL. I traded for this boat to put on the lake up here at home an leave it slipped. That way All I gotta do is just go to the lake. Its a 20'er and I plan to leave it open an carry lawn chairs to it. LOL. Thanks all.......... Mac
     
  10. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    It would have the drain plugs in it even if it was foam filled. I put just a small amount of air in mine to use soap water to check for leaks.
    If you gonna slip it I would extend the fence all the way to the front to have all the walking room I could get. I have a 24 footer and am in the process of obtaining the fencening to do just this.
    Be real carful about fishing from a pontoon. It will spoil you and the boat will set a lot and the toon will be used regularly.:wink:
     
  11. Little Mac

    Little Mac Active Member

    Messages:
    1,828
    State:
    NW Arkansa
    I sounded those toons yesterday and they sound empty, would there be any problems with filling them with floatation foam?
     
  12. Katmandeux

    Katmandeux New Member

    Messages:
    1,618
    State:
    Checotah, Oklahoma
    I don't think I would foam the logs. It will add weight, and foam will, over time, absorb water. Then you really would have a mess.
     
  13. Mark J

    Mark J New Member

    Messages:
    9,407
    State:
    Four Oaks, NC
    Nope. I know someone that did this on a 28 footer.
    Of course he owns a fab shop and mega dollars worth of equipment.

    He went along the top of the toons and cut 3" round holes every so often for his pours. He didnt pour to the top of the toons. He welded a diamond plate patch over the holes.

    2 areas of concern. Blowing the toons apart with expanding foam. Got to be real careful.

    Later if you gash a toon on a rock or log you can probally rule out welding a repair. You'll have to get creative with some sealant and pop rivets.

    I may wind up going the foam route with mine at some point due to the pitting I have but not just yet. I said from the beginning this pontoon was going to be a test bed for some different things and different approaches.

    So far I've used 3 products on some bad spots and cracks.
    HTS-2000- Buy 2 pounds to just to learn with. It has its pecularities even if you are accustomed to brazing. Heat is one of those. If you arent careful you will oil can a pontoon or burn through it. I've done both. Its neat stuff. I'll always keep a few rods and a Mapp gas torch on the pontoon for emergency repairs. I think I bought a 2-1/2 pound package for a 100-125 bucks. Works great for filling in holes that have been drilled in the aluminum fencing. Fill it and grind it smooth.

    Loctite's Aluminum putty- Its an epoxy type prodcut that is in paste form.
    Dries hard and sands. Alot of people use it on toons. Easy to mix and use.
    The only problem is it looks like a patch unless you coat the toons which I did.
    Sold by the pound. I think a pound was around 35 dollars.

    And I've used metal filler to fill in some pitting just to fill the space. Its not going to add or replace any strength but it preps the surface for a good primer and topcoat. Its hardener is like whats used for polyester fiberglass resin. I believe this is an evercoat product and is 25-30 dollars a quart at NAPA.

    My primer was 2 coats of self etching primer. One coat down and the second coat was a flash coat 5 minutes later as directed. I used cans as my shop isnt set up. I got the large spray cans from NAPA. The name escapes me right now but was recommended as being the best available. 15 dollars a can. 8 cans for 2 pontoons below the waterline.

    My top coat was 22 coats of rolled on (6" foam roller) Eco tuff below water polyeurathane paint with no aggregate.
    I can roll down the length of a pontoon and start again at the other end.
    It dries to the touch fast but takes up to 7 days to reach full cure.
    It doesnt require mixing a hardner in.
    Takes about 1-1/2 gallons to coat 2-24' pontoons 3/4 of the circumfrence with 22 coats.
    It goes on thin but is a buildable coating.
    It seems to be a tough as nails coating. I can take a wire brush to it and manage to dull the finish. The wire brush doesnt take the coating off.
    I'd have to sand blast it off or grind it off.
    The product was actually made to coat concrete floors, swimming pool walls, saunas, whirlpools, fountains, etc. It comes in I think 19 stock colors.

    I learned the hard way with this coating. I rolled a few coats on and went to work. Later that afternoon the sun popped out and even though it wasnt a hot day those toons gather and store heat. I had some blistering as a result.
    I had to go back with a razor blade and cut back and strip the blistered spots , reprime and pick up with the coating. After 22 coats its not noticeable unless you know what you are looking for.
    My suggestion is if you use this coating do it under a roof or in the shade.

    My pontoons are 30 years old . I dont have a thing to lose in trying a few things. The perfect test bed.