From old NG post of Howto, probably need to be read along with the one
above.


Norma,

How disappointing, but fixing the boat, learning new skills is almost
as much fun as the boating itself. (I'm kidding but it might make you
feel better). Sorry for the delay & length of this reply.

I'm making some assumptions (again) but indeed it sounds like the
transom has
failed, probably because the core was plywood & over time has rotted.

It's a big job, but not too complex & even if you choose not to do it,
it might help to know what needs to be done.

The transom is from the outside in is, fibreglass, plywood then
another layer of fibreglass. Sounds like the load from the motor has
actually broken the inner & outer skins along with the plywood
obviously. Have a really good look at it & you will see what
has happened, don't be shy about poking/drilling holes to be absolutely
sure it is a rotten transom, it might have hit something & not been
properly repaired, not likely but
be sure.

On the assumption it is the transom, to repair you need to strip all
the machinery off the stern of the boat, motor, steering, wiring, fuel
filters/lines etc. etc. also peel the rubbing/cover rubber off for a few
feet along the hull.

Using a 4in. grinder (wear goggles & dust mask) with a metal cutting disc;

(i) you'll probably need to remove the outboard well, this will need to
be cut where the deck is bonded onto the hull (don't try to remove any
fastenings just cut them) & unfortunately you'll need to continue the
cuts along each gunwale until level with the forward end of the outboard
well, then across to deck into the inside, now the outboard
well should lift out,

(ii) cut all around the inside of the transom where it joins the hull,
but not too deep, you only want to remove the inner skin, (if the floor
goes all the way back, cut & remove enough out to give yourself plenty
of room)

(iii) now with hammers & chisels remove the transom inner skin (try not
to destroy it too much as you can use it as a template to cut the new
transom core later on), then continue chiseling getting all the old
plywood out, now with a metal grinding disc, completely grind the entire
area until there is no trace of the old wood or it's bonding
agent attached to the transom which you will be leaving in situ, grind
along the hull sides bottom etc for a good distance to give plenty of
fresh cleanly ground area to bond to, also tidy up around the gunwale
where you removed the O/B eng. well & under the well where it bonds to
the gunwale. (keep everything all dry & clean)

(iv) Find your local fibreglass supplier, commercial not a hardware
store or such & get your materials you will need all that is mentioned
below, except the woven cloth should be heavy, at least 800 gsm, plus
you need a new core for the transom, there are new materials
now that are very strong, bond well, don't rot & are specifically
designed for transoms,your supplier can advise, but if you are stuck use
ply again, you'll need enough to make the core 2 in thick min, you will
also need some bonding agent, (a fair bit actually) use a brand
"probond" but be guided by your supplier.


(v) The repair is as follows;
(a) using the old inner transom as a template, cut the new core to the
correct shape,
(b) completely coat the inside of the old outer transom with catalysed
probond & the outer (stern) side of the new transom core, then place the
new core into the boat, drill some holes through where the old engine
mount bolts were & bolt pre-prepared timbers inside & out, to act as a
press to get the new core well bedding in against the old outer
transom & hull perimeter, if it doesn't look right, drill some more
holes & use more bolts/wood or whatever, you only have 15-20 mins & any
extra holes in the transom can be simply repaired later.
(c) after the probond has gone off, a final tidy up with the grinder,
you can glass a new inner transom in, being careful to ensure that each
layer is glassed to the old hull & not just the layer under it. (i.e.
each successive layer travels slightly, say 1.5in. further along the
hull) Inside there is no need to "finish" it off too much.
(d) using probond, as with the transom core, replace the outboard well &
put new fastenings into the deck shelf, where you had to cut across the
deck there will be a gap the thickness of the cutting disc, put some
small nuts & bolts with biggish washers on to align the two edges, under
the deck, put some glass between the bolts, later remove the bolts
(grind them out) & glass over the holes from underneath, this area is
more than cosmetic so don't skimp under the decks.
(e) the only "finishing" needed is the two small cuts across the deck,
the original holes left in the outer transom & any additional holes you
put in the transom to help draw the new core into place.
(f) in your travels if you come across any other rot or problem in the
boat, the repair is much the same & by this time it'll be a doddle for you.

Don't hesitate to ask, the NG or your fibreglass supplier if you have a
problem with what & how it's done, "before" you start:-)

Karen Smith