74 MirroCraft F-3616 Build

Hi all,

I've been a long time lurker, and I finally decided to rebuild and modify my 74(ish) MirroCraft F-3616. She is 16' and very deep for a tinny. The boat was owned by my Grandpa and passed to my Dad, who then gave to it to me after I moved to the shores of Lake Michigan. I've had the boat going on 3 years, and it came with a 25hp Johnson that has given me fits the last year.

I also plan to freshen up the trailer, if the budget allows!

The first order of business is to paint the outside of the hull and assess the trailer. I don't have much room to flip the boat so I made a lift in my garage to pick the boat up, get the trailer out and then lower the boat onto blocks for stability.


I'm sure I'll improve on the image posting as the project develops. How the heck do I rotate the pictures?

Once the boat is complete she will be repowered with an ETEC. Here is the laundry list of things I may or may not do.

Put in flooring between the seats
Casting decks front and rear
Relocate the side console one seat forward, right now it is in a terrible position for trolling
Upgrade pulley steering to a teleflex
Remove the front bow cover
Assess transom and rebuild or reinforce
Add side storage compartments
Fill holes in the hull from the pulley steering removal
Paint inside and out
Rewire
Trailer work

Of course all is subject to change based on budget, time and level of frustration!

Just got back from the car wash, hosed off 40 years of crud from the trailer

Here is a 74 Mirrocraft sales brochure, if anyone is interested.
View attachment 1974 Catalog.pdf

This week I'm going to start rehab on the hull, and prime the trailer. I'll be using Duralux aluminum boat paint on the hull, since it is a one step coating. Coat-it epoxy on the inside rivets and seams as insurance against leaks, then topped with more Duralux.

Trailer will be primed and topped with an alkyd enamel.

[url=https://www.tinboats.net/forum/viewtopic.php?p=352687#p352687 said:

DrainBamage » 18 May 2014, 16:38[/url]"]Just got back from the car wash, hosed off 40 years of crud from the trailer

Here is a 74 Mirrocraft sales brochure, if anyone is interested.


This week I'm going to start rehab on the hull, and prime the trailer. I'll be using Duralux aluminum boat paint on the hull, since it is a one step coating. Coat-it epoxy on the inside rivets and seams as insurance against leaks, then topped with more Duralux.

Trailer will be primed and topped with an alkyd enamel.

Click to expand...

Love those old brochures! They are always fun to check out!

DrainBamage,

Any updates on your mod?
I too have a closed bow tin. Contemplating on removing the bow cover as well. I'm very i terested if you went through with removing the bow cover.
C'mon now!

I haven't gotten to the bow cover as of yet. I've disassembled the trailer and sanded the frame plus about a quarter of the hull. Nothing exciting so I didn't take any pictures.

Next is lengthening the trailer tongue, then paint, new rollers, and bunks. I have 4 days off for this starting friday and should get the trailer done and quite a bit of the boat sanded.

Looking at the bow tin cover, the dang thing might be structural. It also has floatation foam, so a creative compromise might be in order. If it were only just a foot shorter.

Anyone have recommendations for outboard size? I'm thinking a 30hp ETEC will get her up on a plane with a few passengers, added weight of the floor and decks, gear, etc. The old 25 i had on there could plane with 700lbs in people and equipment. The next step up from there is the 40hp, which is dang heavy in comparison and a lot more cash.

OK, I've spent a fair portion of the long weekend hacking away. Trailer frame is complete including bearings and races, the fenders and other small parts are prepped and due to be painted by a friend sometime this week. The transom is also out of the boat now, which I'm glad I didn't risk leaving it in. Soft in some spots and delaminating in others.



And











Next is the clean up and paint where the transom was, cut new 1/2 BC ply and make a 3 layer laminate for the new transom. As time allows I'll continue to prep the hull for paint.

I've decided to go with mdo for the floor and decks. I'll basically make a cap out of mdo using scarf joints that will span the seats along the sides. I hope to have a seamless appearance for the top coating of gator grip.

[url=https://www.tinboats.net/forum/viewtopic.php?p=353103#p353103 said:

Rob Silver » 21 May 2014, 22:05[/url]"]DrainBamage,

Any updates on your mod?
I too have a closed bow tin. Contemplating on removing the bow cover as well. I'm very i terested if you went through with removing the bow cover.
C'mon now!

Click to expand...

The bow cover is off. And it was a PITA. Rivets were easy enough, but it is just about impossible to get the bow brace screws out since there is foam under the cover. Had to grind the heads off. Only then will the cover come off, leaving all the foam behind. The cover by itself is definitely not structural, except for the brace of course.

The worst part was getting the foam out, it actually adhered so well alot of the paint came off with it. Then the little left over pieces had to be scraped with a razor and hit with a bronze wire wheel.

All the holes from the cable steering are patched along with all other holes including from the bow cover. Also all rock rash on the keel was filled in. I used jb marine and jb waterweld. Both jb products stuck incredibly well to the aluminum, which was prepped with coarse sand paper and cleaned several times with white vinegar to etch the aluminum.

The entire hull was scuffed up on the outside and will be painted tomorrow. The transom is nearly complete, I have all new bolts and screws to install it. Just one more coat of epoxy to the 2x4 brace Mirrocraft used on the transom.

Console is out, primered, and will be painted. Once dry it will be reinstalled one bench forward of its old location.

Pics soon.

DB,

Really looking forward to seeing pics of the bow cover removal.
By your description, it looks like a lot of work......but the payout will be more than worth it!
I will keep on checking in on your build and probably mirror what you do.

Good luck bro!

Painting is going slower than I expected, I don't want to cut corners so it is meticulous work prepping with all the rivets on this thing. I am just about done with painting, just some touching up and a few coats on the console are left. After that I will mount a small cutting board to serve as the new transducer mount, mount a few odds and ends like oar locks, seal up a few transom bolts with 5200, and drive it to the dealer for a 30hp etec.


I highly recommend the Duralux Aluminum paint, it sticks to bare aluminum and is some tough paint. Too bad it only comes in one color.

Here is a good look at the boat without the bow cover, lots of space up front now.

I ended up using Rustoleum Topside paint, sand color. Happy accident, but that color of Topside is an exact match for the regular Rustoleum Almond that I used on the trailer. Never thought I'd have a paint matched trailer. Also, the console has been moved up one bench for a little extra room in back.


It took many bottles of Newcastle to get me to this point. Once the new outboard is on, I can finally go fishing and save the improvements for rainy days (literally) and after work a few hours each day. Just in time for the Salmon action to start kicking up on Lake Michigan.

Console and gunnels painted, touch ups complete, odds and ends sealed with 5200.

Also had time to wire up the lights, battery, and depth finder. Plus installed all the USCG required stuff including a new capacity plate I bought from Mirrocraft last year.

She is ready to be repowered, dropping her off tomorrow after work.





I'll need to catch up on some around the house stuff before I spend major time on the modification stage. But on rainy days I will be making a motor well of sorts, something to mount down riggers and flush mount rod holders on. Part of that will incorporate a rear casting deck.

So my major question to ponder, is to go with carpet, vinyl, or some type of coating? I'm inclined to go with a non slip epoxy coating like they use on floors.

Drain,
Very nice build, and good to see another wisconsinite on here.

Check out my build in progress, I have flush mounts and space for riggers. Maybe will help with some ideas.

Pics or it didn't happen?


All I can say is, this outboard is incredible!

Mgros, you pretty much hit the nail on the head with your build. I'm essentially doing the same thing so I can have the downriggers in the stern corners with flush mounts spanning in between. I'd also like to get a pair of big jon heavy duty rod holders, putting a double behind each downrigger. But that might take a little time, $500 for the two.

Not sure how much if any progress I'll make this weekend. I've got lots of other things to take care of. I am going to make time to get the boat in the water and open her up. I want to get some GPS speeds before I start putting in all of the decking.

Well the new motor is showing the boat who is boss. The extra weight of the console moved up front and the bigger motor has revealed some rot in the front bench. Sagging in one corner. That means all 3 seats are coming out for repairs. I still have quite a bit of 3/4 marine grade and epoxy left, so it will be a no cost repair.

As for the 30hp ETEC performance, you'd swear it was twice the HP of the old 25 seahorse. With 12 gallons of fuel and almost 400lbs between the two idiots inside, it topped out at 26mph per GPS. The combination of power trim, and movement of weight forward with the console move allowed a cruise at 20mph without pounding even in the heavy chop. The old motor and console location resulted in a severe beating in those conditions, since the nose rode so high all the chop slapped the bottom.

Good riddance to the old seahorse, it could barely eek out 17mph at WOT with two adults.

Since the front bench needs repair, I started to think about the front mods. Does anyone have an old mirrocraft console they'd like to sell? Setting up a second one sounds like a good idea, a glovebox of sorts.

Quick update. Found a marine radio at a garage sale for $20, its older but its all I need. A good friend also felt his fish finder was way too much for his 12' tin, so he traded with me. I gave up a humminbird 160 something for a 561! He often fishes with me, and wants to contribute on this boat build so we can slay some Kings out on the big lake. Also bought gas tank straps, 12 gallons sliding around always made me nervous. I have marine grade rubber weather strip to put on the ribs where the tank sits. Got some nice camo seats on sale fleet farm, and the mounts are in the mail as we speak.

So I pulled a bench to start r&r of the wood reinforcements. I will be adding a knee brace since I'm using epoxy to build the new reinforcements. The original is basically an offset T of 3/4 ply and a 3/4 piece of pine. In the pic, it basically sits in the gap at the top. The ply does not run the full length of the bench, The shape of the aluminum bench shell and the foam filling is pretty darn rigid.



Now that I've pulled the bench and seen exactly how its built, I'm committing on an idea I've been thinking about since the project began. I will be attaching a piece of 1/2 bcx plywood to the bottom on each seat, secured to the aluminum lip and the reinforcements I'm replacing now. The ply will be spar varnished because I'm almost out of epoxy, which I'm saving only for the bench reinforcements as mentioned. I will then hang 2x4 western red cedar 12" oc running the full span between the seats to serve as the floor joists. I figure if one bench can handle 400lbs of idiots catching air and pounding chop at wot, then all 3 benches can handle those same idiots plus a floor that weighs less than 100lbs total. Plus the additional ply and knee braces should make the seats even stronger. I have yet to figure out how I will secure the 2x4s to the bottom ply.

So I need to consult anyone with an opinion, see any faults with my plan? Any insight how to secure the floor? Maybe some t-nuts and thru bolts?

Bench seats are out, old wood is removed and new replacement wood cut, fitted and screwed together with bracing. Each piece will be disassembled, epoxied, and reassembled before final install. The added bottom plywood mentioned the last post will be cut later in the week. Decided to go with T-Nuts to install the floor joists.

Your boat looks great. You should have plenty of storage under your deck. I'd look at a fuel tank for under the bow deck. Are you going to be adding foam as well?

Thanks for the compliments! I am considering an auxillary tank up front, but the boat is perfectly balanced right now, I can trim up to gain a few mph at cruise and trim down to slice through the chop and add holeshot. The extra weight of the decks and flooring might effect this later on, but I will build the compartments to fit an extra 6 gallon tank in case things get stern heavy. I also want to be cautious about adding too much extra weight, at some point even the new 30hp ETEC will be a turd for Lake Michigan. "They" say never go further from safe harbor than 15 minutes distance at WOT, since the lake can get angry at a moments notice. I seriously limit my fishing options the slower the boat becomes. As of now I can reach over 7 miles offshore by that rule, which is where mid season action is at.

For the same reasons, she is getting lots of foam. Between each joist will be pink foam board cut to size and glued to the plywood, as much as I can fit without touching the ribs. Also will be looking for other places to stuff foam for upright floatation in case we get swamped. Seen a boat get swamped out there once, upright floatation allowed them to still drive the boat and get back alive. Some day I'll buy a cabin cruiser for serious offshore all weather LM use, but my boat is fine for near shore when exercising common sense, something I had less of 2 years ago when boating was new to me.

I got stuck in 4-5 footers two years ago, total stupidity on my part for even being out there, but that is all one needs for learning a lesson. That lake is humbling, makes you realize how small and fragile humans are, we were a dang bath toy for about 2 hours. The looks on peoples faces when we went past the lighthouse in a little 16' boat, lol.

Bottom pieces cut, t-nuts installed, and first coat of spar varnish is on. The bench supports are epoxied. Tomorrow morning will be a second coat of spar, then after work the benches will be reassembled and installed in the boat. Paint touch ups, and the aluminum corner braces on the hull will see the bolts removed and 1/4 inch pop rivets in their place. The braces have too much wiggle and I'm afraid of wallowing out the holes over time. Other odds and ends if time allows. Hope to be perch jerking on Green Bay this weekend.