1977 Mirrocraft V-hull repairs

rmfish99

Recruit
Joined
May 29, 2024
Messages
2
Hello,
I have inherited (after being passed around to other family members) my grandfather's 1977 Mirrocraft V-hull with a 1982 25-hp Evinrude tiller motor. The boat has 3 bench seats and a bow step. The original transom rotted out a few years ago and was replaced with a pressure-treated 2X. I brought the boat into my shop to get the transom replaced. The front seat has curved down in the back for a number of years. I just thought the aluminum had stretched/ bent, but after further inspection, I realized the seat has 3 wooden supports and the back one has rotted. The side panels that protect the foam have also rusted significantly.

So I have removed the transom and there is some corrosion underneath but it doesn't seem too bad. And I have torn the front seat apart. The wooden supports look like basic pine boards. I am surprised they have lasted this long. There are also some cracks in the support bracket connected to the boat that will need to be welded.

I want to repair this as best and permanently as possible and was hoping to get some good advice, so here are some questions.

For the transom, I was thinking of replacing it with an aluminum one. Is Tiny Boat Nation the best source? Other suppliers?
What is the best way to clean up the corrosion? wire brush, vinegar, or other acid product (Lowe's has a Klean Strip concrete and metal prep product)?

For the seat, the boards are 3/4 X 2 1/4 inch. The only aluminum tubing I see that might work is 3/4 X 1 1/2 inches. Would this work or does it need to be wood? Any good suppliers for the aluminum tubing? Prices are all over the place for the long stuff.
I'm going to check with my local sheet metal fabricator to see what my options are about replacing the sides.

Thanks for your help,
Rob
 

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jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
13,478
Welcome to iboats

Looks like a 14' Deep Fisherman from the late 70s. We had 2 of them in the 80s
The Pressure Treated Wood used to replace the Transom, wasn't the Best Choice, and likely caused the Corrosion
Marine Grade Plywood, epoxied to the Correct Thickness should last at least 20 years, as the Wood is will be able breathe, by not painting on the Bottom, just make sure to apply a Sealer to any Screw/Bolts going thru the Transom
Can't comment on the Seat Repairs as we didn't keep the Boats past 15 yrs

mirrocraft2.jpg
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
49,896
The pressure treated plywood will galvanically corrode the transom
 

rmfish99

Recruit
Joined
May 29, 2024
Messages
2
I knew about the evils of pressure-treated wood and aluminum. That's what started me down the repair road.
I really like the idea of the aluminum transom, just bolt it in, no cutting and sealing. Are there any real downsides other than cost?

I was hoping someone had experience with the aluminum supports in the seat. When I look at some strength calculators, the aluminum has less deflection than wood. But it is expensive to just try.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
49,896
Just use exterior grade plywood and a can of Rust-Oleum oil base paint. It will last 40-50 years
 
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