repair / cover screw holes under the step in the hull

[bassdge]

I just updated my flush mount transducer. it is mounted flush under the step in the hull. the new transducer bracket screw holes are not as wide. I was able to use 4 of the existing holes on the right side of bracket but has to drill 4 new holes on the left side. I now have 4 empty screw holes under the step. I put silicon in them as I was putting in the screws for the bracket, but quickly regretted doing that.
What is the best way to prep and seal these holes to protect the fiberglass and gel coat since they will have water running past them up to 70ish mph?
Thank you

[92basshawk]

3m 5200 is pretty permanent. Id try to clean out the silicon and scuff the gel around the holes. Being on the roof of the step it should be out of the harshest flow at the highest friction events.

[crank68]

If you’re not bent on fixing them correctly....Marine Tex will work nicely. Just do as stated above and clean out the existing silicone.

[rojoguio]

My go to is West Systems 105 Epoxy w/Fast Cure Hardener, thickened with 404 High Density Filler to peanut butter consistency. This is injected into the bottom of the hole pulling the West Systems Syringe outward as you fill, leaving a small, proud, cap of the epoxy to slice off with a razor blade when semi cured. Done right it will be there forever.

[illinifish]

If you’re not bent on fixing them correctly....Marine Tex will work nicely. Just do as stated above and clean out the existing silicone.

I have used marine Tex many times over the years to fill holes when changing transducers. Never had an issue. I try to find auto touch up paint that is the same as the hull and paint over the repair

[plbass]

My go to is West Systems 105 Epoxy w/Fast Cure Hardener, thickened with 404 High Density Filler to peanut butter consistency. This is injected into the bottom of the hole pulling the West Systems Syringe outward as you fill, leaving a small, proud, cap of the epoxy to slice off with a razor blade when semi cured. Done right it will be there forever.

This will work nicely.

[willwork4fish]

If the old holes had silicone in them then I'd suggest drilling them out a little bigger before you use Marine Tex or any kind of resin/peanut butter. Either one will work fine to keep the water out.

If you plan on prettying up the area with gel than you should use polyester resin and some silica to thicken it. You can get a quart of Total Boat resin and the silica for like $40 from Jamestown.

[OnTRAK]

My go to is West Systems 105 Epoxy w/Fast Cure Hardener, thickened with 404 High Density Filler to peanut butter consistency. This is injected into the bottom of the hole pulling the West Systems Syringe outward as you fill, leaving a small, proud, cap of the epoxy to slice off with a razor blade when semi cured. Done right it will be there forever.

I did this but but stopped filling just below the level of the gel coat. I let it cure, roughed it lightly with small Dremel grinding attachment, then tinted some Marine-Tex with a gel coat coloring agent to match the color of my gel coat and filled the remainder. Then wet sanded to level, buffed & waxed the small area. The repair is almost invisible.

[rojoguio]

I did this but but stopped filling just below the level of the gel coat. I let it cure, roughed it lightly with small Dremel grinding attachment, then tinted some Marine-Tex with a gel coat coloring agent to match the color of my gel coat and filled the remainder. Then wet sanded to level, buffed & waxed the small area. The repair is almost invisible.

Very Nice Touch!

[bassdge]

My go to is West Systems 105 Epoxy w/Fast Cure Hardener, thickened with 404 High Density Filler to peanut butter consistency. This is injected into the bottom of the hole pulling the West Systems Syringe outward as you fill, leaving a small, proud, cap of the epoxy to slice off with a razor blade when semi cured. Done right it will be there forever.

I see West Systems has a small kit with the 105/205 and the 406 filler https://www.westsystem.com/handy-repair-pack/
will the 406 be fine for the task?

could you add a coloring agent in this or would it affect curing?

[rojoguio]

406 is just a thickener but I have spoken to Tech Support at West and a 1/4in buildup does not seem to worry them much when fairing so I would say since filling a hole it would work fine. The oils epoxy generates when curing will wipe off with water. Do not use a solvent for removing before prepping for further finishing. That came from Tech Support also. I like to use Acryli-Clean, a PPG Refinish product for final wipedowns. Very easy on the under work, not hot at all.