Transom repair advice needed

Discussion in 'Fiberglass and Composite Boat Building' started by MotorHead, Sep 8, 2007.

  1. PAR
    Joined: Nov 2003
    Posts: 19,126
    Likes: 498, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    You don't need a lifting eye, many things will easily yank that engine off your transom. Two well fed friends can do it, a boom style of engine hoist has more then enough clearance to lift it, a come-a-long from a tree branch, a chain fall from a similar tree branch, hell, I've even used a block and tackle to hoist engines up before, when I had nothing better. It's not that heavy, doesn't have to lift very far and isn't a real big deal. Have a hand truck near by so you can wheel the beast to some place safe.

    Charlie had it right and unfortunately you only have two choices (three if you count doing nothing), removing the material in the transom or drilling, likely around several hundred holes.

    This isn't that uncommon a repair, more often seen on delaminating plywood bulkheads or sheered cores that would prove very difficult to remove or replace, but it'll work here as well.

    Once the outboard is off the transom, lower the tongue jack as far as it will go. This will cant the transom pretty plumb, so it doesn't fight you as you fill the holes. If the transom isn't plumb or better actually facing up a little, then jack the trailer axle up and support it, so the bow can drop down more with the lowered jack.

    Start drilling holes, say 1/8" or 3/16" on 1 1/2" centers (yep, that's going to be a lot of holes). Drill at a downward angle (10 degrees is good) to help the goo flow into the hole. When you're drilling you'll feel the voids after the bit punches through the hull shell. When you feel this, stop and start the next hole.

    You now will have a transom that looks like a well organized pin cushion. It's goo time. Mix up a very slow batch of epoxy and add some milled fibbers, until it is a very loose, very running, milky mixture. It has to flow reasonably well. Place this mixture into a squeeze bottle and then squirt it in the holes. It'll try to squirt out, so use some pressure to keep the tip of the squeeze bottle engaged with the hole. After several holes are filled, wipe the excess off with an acetone dampened rag, let the acetone flash off then put a piece of clear packaging tape over the filled holes (start at the bottom and work up). Continue filling, wiping and taping until you've done all the holes. Then go back and do it again. Many will not accept any more (or very much) goo, which means they're full. Some will want more goo, so fill them up and tape. Do this until all the holes will accept no more goo.

    Fair and paint the transom then reassemble the shooting match. Yep, it sucks, but it's easier then ripping out all the materials and work that has been done. We've all had to go over and fix someone else's issues or rectify poor workmanship. I feel for you Skullhooker, but you're transom needs to be pretty bulletproof, especially with big HP engines hanging on them.
     
    2 people like this.
  2. rwstoney
    Joined: Jan 2005
    Posts: 4
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: New Jersey

    rwstoney New Member

    transom rebuild

    Having rebuilt the transom on a 1973 boat my one word of wisdom would be to go for a 25" transom height. The 20" transom leaves a big hole in the back of the boat where waves can come in presenting a safety issue. A 25" shaft outboard is not much more than a 20" and much safer with the higher transom.:)
     
  3. fiberglass jack
    Joined: Dec 2005
    Posts: 463
    Likes: 16, Points: 0, Legacy Rep: 95
    Location: toronto

    fiberglass jack Senior Member

    :D :D :D :D Par when are you going to write a book
     
    1 person likes this.
  4. skullhooker
    Joined: Sep 2007
    Posts: 24
    Likes: 1, Points: 0, Legacy Rep: 19
    Location: Indialantic, FL

    skullhooker Junior Member

    Oh yea, Thanks Par. I bought the lifting eye from Bob's Machine Shop, about 50 bucks delivered (otherwise a $120 dealer part), works great with my dad's chain hoist (awesome tool). motor was real easy to remove, and no sore back or motor damage.

    Have probably drilled 75 1/4" holes, and am 3/4 done with filling them, has taken about three 2 hour sessions thus far. A doctor friend gave me some 60 cc syringes, which I attached a short length of 1/4" clear poly pipe with the end cut at an angle, fits tight in the holes with no squeeze-out on the sides. If the holes were taped fast we didn't have to use the acetone wipe. Acetone is nasty stuff, but your technique works great.

    A weird thing is how when a hole was injected, a neighoring hole maybe 2 or 3 holes away, started oozing, like some underground gopher holes in the gap delamination. Some holes wouldnt take mach, and others I could pump one or two syringes into. The syringes gummed up in about a half an hour, then I would use another. Am waiting on more syringes to finish the job.

    What a mess. With all the gaps found in the in the transom repair, I decided to pry off an aluminum 1/4" thick x 4" tall x 3" wide transom cap I previously glued down in a bed of 5200, to check for gaps under it. Well, about two inched down from the top of the transom, there was a horizontal fault line crack, which when scraped down with a mat knife, revealed that the former d*?#head repairer had formed a cap of putty, instead of a laminate cap, and simply gelcoated over. I was going to put the aluminum back on and seal it over, but then I thought that water has a way of finding all cracks, no matter how well you think you have it covered up. So now I'm gonna remove the 5200 mess, grind down the top putty, grind taper the hull and inner liner skins and laminate a top skin about 1/4" thick. Then I'll sand & fair the whole thing, re-gelcoat, glue the cap back on, and hang the motor back on. No problem :), whew!
     
  5. PAR
    Joined: Nov 2003
    Posts: 19,126
    Likes: 498, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Good point Jack. If I collect up all the posts in every thread, I'll have a fine start. So, you want to be my editor? You can work on commission.

    Yep, Skullhooker, that oozing thingie is also common. The plywood can have voids (common in exterior grades of ply) which will make perfect little highways for the goo to travel from one hole to the next (and why I said start at the bottom and work up, this way you're always filling). Syringes are the way I do it on small holes or lifted laminates, but 1/4" is big enough for my favorite squeeze bottle.

    I hate 5200 for this application. You're better off filing that sucker full, grinding it smooth at the top and sealing it off with a well bedded cap.
     
  6. skullhooker
    Joined: Sep 2007
    Posts: 24
    Likes: 1, Points: 0, Legacy Rep: 19
    Location: Indialantic, FL

    skullhooker Junior Member

    Par, what kind of squeeze bottle do you have, something like a refillable catsup bottle? I have a couple, but it looks like I would waste a lot af material and the cap might pop off when presuure is applied.

    And what do mean by filling it full and sealing it off with a well bedded cap? The aluminum cap I made is also for abrasion resistance cause I'm always stepping on it when boarding from the swim platform, smacking it with fishing rods, nets, gaffs, skis, etc. (and the boat originally came with a similar lighter gauge alum cap from the builder),
     
  7. PAR
    Joined: Nov 2003
    Posts: 19,126
    Likes: 498, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Fill it with epoxy, grind smooth, then cap with your bedded aluminum angle stock.

    The squeeze bottle I use is a 15 year old remnant from a "Get-Rot" kit. It's about a 6 ounce bottle with a screw on top that has a tapered spout. The spout is cut, so there's about an 1/8" hole in the end of it. It's narrow enough to slide a piece of 1/4" tubing over for hard to reach areas and I've been using this "favorite" bottle of mine for years. I've seen similar on one of the major epoxy manufacture web sites (West, System 3, etc., don't remember which).

    The small bottle forces me to use small batches, which is good as it'll kick pretty quickly in the confines of a bottle. I rinse it out with vinegar and a final rinse with a special epoxy cleaner.

    Unless you're working directly down hand, you'll waste some epoxy, but small amounts really. I get more on my shoes then I waste.
     
  8. ratrace2
    Joined: Dec 2007
    Posts: 543
    Likes: 5, Points: 0, Legacy Rep: 84
    Location: NJ USA

    ratrace2 Senior Member

    Need to Vacuum after chinking with mat:

    God, you work hard:
    Ya know what I would do. I would chink that opening with mat...punch it in like I was doing a log cabin and then dril a hole in the bottom and such resin through it with a vacuum pump......
     

  9. skullhooker
    Joined: Sep 2007
    Posts: 24
    Likes: 1, Points: 0, Legacy Rep: 19
    Location: Indialantic, FL

    skullhooker Junior Member

    Here's an update: This weekend I had a helper, and we removed the 5200 mess with a pair of sharp wood chisels, slicing diagonally, they cut the stuff off pretty efficiently. I then ground off the remaining stuff sacrificing one 36 grit disk, no biggie, and removed the gelcoat covering the putty. When I ground the 12:1 scarfing on the inner liner and transom laminates, the putty fell out and the top of the transom was exposed. I could now see a couple of pieces of 3/8" plywood stuffed in between the double 3/4" transom and the inner liner. There was a 4" horizontal gap on one side of the splash well, and a 2" gap on the other.

    It was a lot of demo but now being able to see the gaps, I taped up the many holes drilled, and stuffed a bunch of folded up roving into the gaps, and poured resin in. Then I bought some foam board, and made an inner and outer form template, level and positioned, and staple gunned them to the exposed wood. Then mixed up about 24 oz. of resin, mixed with fibers and wood flour (all the filler materials I had) and shoveled the material in the form, troweling it off with a putty knife. It filled all the gaps, and bonded rock hard.

    Now I will apply some more filler to fair the sides of the new core, grind, and lay up the laminate. It's been a lot of work, but this transom is gonna be solid if it kills me.

    Photos added, one shows the crack(see arrows pointing) under the 5200 mess, and the other after grinding, forming, and filling. The white stuff is the paper from the foam board stuck to the resin.
     

    Attached Files:

    Last edited: Dec 18, 2007
Loading...
Similar Threads
  1. Flying Flivver
    Replies:
    1
    Views:
    2,475
  2. dead_eye_dick
    Replies:
    35
    Views:
    21,660
  3. Andrew Courtney
    Replies:
    3
    Views:
    1,954
  4. E350
    Replies:
    38
    Views:
    7,068
  5. GP1998
    Replies:
    17
    Views:
    8,393
  6. davels1
    Replies:
    3
    Views:
    2,727
  7. reelboater
    Replies:
    28
    Views:
    11,772
  8. Canracer
    Replies:
    8
    Views:
    5,047
  9. rovi
    Replies:
    15
    Views:
    7,162
  10. Schoonner
    Replies:
    12
    Views:
    3,513
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.