Just bought a 1985 Sea Nymph FM-161

gsh

Petty Officer 2nd Class
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Jun 9, 2010
Messages
104
I have a little 14' boat that I rebuilt, used and improved over the last few years, and it worked great when my daughter was still little. But she's grown quite a bit and not with myself, her my wife and our little dog in it, it's getting cramped and the weight limit had been maxed out.

Not to mention that my daughter has said she wants to try tubing and my boats little 6hp motor just won't do that.

So I started looking on Facebook Marketplace and I found a 16.5' 1985 Sea Nymph FM-161 with a 50hp Mercury on it and a Yacht Club trailer under it.

The wood is starting to rot out and the carpet is completely shot, but the hull looks to be in great shape. The bilge pump and live well pumps need to be replaced. The tires are completely rotted and so is the winch strap. They need to be replaced before I can even move it.The owner kept the seats in his garage and also has brand new life jackets that never got used as well as a spare prop.

Purchase price for the works was $1,360.

I asked why he was selling it and he says he bought it new in 1985 so he and his son could go fishing together. Now his son has grown up, become a dentist and has bought a really nice boat. So when they go fishing, they take the son's boat and this one hasn't been used at all in the last 8 years other than a quick trip to the lake 2 years ago to see if the motor still worked.

I'm assuming that the motor will need work and the floors and carpet need to be replaced as well as some other minor stuff just to get it back on the water, For this winter though I plan on keeping it at my parent's farm in the barn and will do most of the restoration in the spring of 2020.

Does anyone have any other suggestions as to what I might need to investigate for possible problems?
 

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gsh

Petty Officer 2nd Class
Joined
Jun 9, 2010
Messages
104
I took the boat to a shop to have them check out the motor and they said the engine as only getting spark to one cylinder, but had a consistent 130 psi of vacuum on all cylinders. They also said the stator had broken wires and the trigger wan't working. There was also a solenoid that Mercury did a recall on way back in the 80s. They said the switch box was likely bad as well.

At that point I had to make a decision of finding a new motor or fixing this one since the cost was going to be aver $700 for parts and labor. I figured that if the rest of the motor was good I would be better off replacing parts to fix known issues rather than spend money on a different motor that I knew nothing about. I could have bought a completely new 50hp motor like an Evinrude E-Tec, but that just isn't in the budget right now. Also, the new motors weigh 70 lbs more than the one I have.

I had them order the solenoid, stator and the trigger so I might be able to save a bit of money on the switch box.

No luck. With the new parts in the motor ran OK for a minute then started having issues again. So now I need a switch box.

However, the rest of the motor looks to be in good shape, so I should be fine once the new switch box is installed.

I'll let you know what happens next.
 

gsh

Petty Officer 2nd Class
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Jun 9, 2010
Messages
104
Just got the word from the shop that the motor is working with the new switch box, so I went and picked it up.
 

gsh

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Jun 9, 2010
Messages
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Well, the holidays are over and I'm thinking I need to start working on the boat or it will never be done by the time the water opens up.

My first step is disassembling the floor to see what I'm dealing with and so far it isn't pretty.

Notice the carpet is totally rotted and tears like tissue paper. You can also see the wood is literally falling apart and the underside of the small pieces are still soaking wet even though the boat has been indoors since October. The floor sections are good enough to be used as templates, so that's a good thing.

1-14-20 Bow.jpg1-14-20 Deck.jpg1-14-20 Soaked Floor.jpg1-14-20 Foam.jpg

As I progress I'll post more, but for now it's just disassembly and cleanup.
 

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gsh

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So I got back to the boat after the storm we had and the temperature warmed up a bit (no heat in the warehouse) and got a bit more taken apart. Got the console and the drivers seat mount removed and then took out the remaining wood from the floor. The floor is heavily water damaged, black mold and rot is everywhere, more mouse nests were found and old wiring was removed just to clear the way for more work.

What I thought was a factory seat location next to the driver turns out to be a home made mount and it looks like they may have cut a stringer to do it. The screws holding that piece of aluminum down are corroded and won't come loose, so I'm going to have to grind them off or drill them out to remove that piece of aluminum sheet and find out what they did.

Now I need to remove the rotten foam and see what else is wrong. I'm just glad I'm starting now so when warmer weather comes I can have the boat gutted, any repairs made, wiring started, hoses and tubing for the bilge and live well replaced and the floors cut to size in preparation for glassing. Then I can finish the floorboards, add foam, assemble and be done.

At least that's the plan. Who knows what will actually happen.
 

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gsh

Petty Officer 2nd Class
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Jun 9, 2010
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The last few days have left me plenty sore. I've been removing the foam from the boat and doing some more disassembly in preparation for getting repairs done.

The damaged stringer is going to get repaired by welding some 1/16th" aluminum to it and a proper seat mount will be installed just behind that stringer.

If you look at my previous post you'll see that the old pfoam was blocked in with 2" styrofoam sheet against the supports running down the length of the boat. That's all well and good, but the supports on the starboard side were farther from the center and this left a LOT of empty space that probably should have been filled with foam. To remedy this I plan on riveting in some 1/16" x 1 1/12" angle aluminum closer to the center line to hold the new blocking.

The foam in the sides is dry on the bottom, so I plan on leaving it in place except for where I need to run some wiring and plumbing. So my next task is to figure out how to remove the foam in those areas.

Finally, removing the foam in the front showed just how much they had in there and gave me the idea to maybe add a storage area under the deck right there. Still haven't made up my mind about it yet, but it's an interesting idea.
 

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gsh

Petty Officer 2nd Class
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Jun 9, 2010
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Just remember no treated plywood with aluminum.

I was planning on using standard plywood and using epoxy resin and a layer of fiberglass on both sides to preserve the wood. I figure that should keep the floor good for at least 10 years,
 

gsh

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Well, I changed my mind about the foam on the sides and will end up removing it. Not only is it 35 years old, but it doesn't seem to be closed cell foam

I wasn't sure about the best way to do this so I looked around a bit and someone on here had used a drill bit extension and a cup brush. I tried it and sure enough it turns the old foam into dust REALLY fast. The only problem I saw was it only worked in a narrow path straight down. So I tried using a 3" nylon flap brush and attacking it from the side. That worked even better because it also peeled the foam off the side of the aluminum.

I'll try and include pictures later.
 

gsh

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Jun 9, 2010
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Here's a picture of the foam on one side after about 2 minutes of work and using first the cup brush and then the flap brush.

Here's a short video showing the cup brush in action.

https://youtu.be/bJn-5JlvsVw
 

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gsh

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Well, I finally got the foam out of the boat and upon closer examination of the exposed ends of the transom, it's going to end up being replaced. The wood was literally crumbling into black dust when I touched it. Not really surprised, but it's a bother.

So the question was replace it with wood or composite?

I got the rough dimensions and called boatoutfitters.com to get a quote. A single sheet of 1.5" Coosa was almost $600 and the freight would be over $200 for a cost of $809.

A sheet of 3/4" Coosa would be $540 delivered

However, a single sheet of 3/4" non-treated AB marine plywood costs $78 and is available at the local Menards. Since it's just going to be wood, I plan on using epoxy and woven fiberglass mat to make it a bit stronger, but primarily to seal it up. I also plan on fiberglassing the wood for the floors on both top and bottom.

Now that all that is decided I have a question for those that have done similar projects. How much resin and fiberglass do you think this would take on a 16.5" boat? I'd rather get enough the first time out than start, then wait to get more.
 
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chevymaher

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WOG example list. I know yours is a tinny but this was right on the money for mine. I did end up getting more. But as you work you know when you need more order it and it gets there before you run out.

WOG’s Suggested Materials List for Total Restore of a 16-18’ 3 - Stringer Boat.
It's impossible to give an exact "Quote" of everything you'll need but this list will get you "Started" and from there,
after you've done some "Glassin" you should have a good idea of what you'll need to "Finish-UP"
Here's the Starting List.
PPE
Respirator (Full Face Preferred $100) if not then double filtered 1/2 face and Goggles with vents
taped over.
Latex Gloves (1 – 2 Box(s))
Leather Gloves 1 Pair
Full cover Hooded Tyvek suit. (Rubber Band or Tape the Wrists and Ankles, wet Towel around your
neck)
Talcum Powder (coat yourself TOTALLY with talcum powder prior to every grinding Session. USE A
LOT)
Demo Equipment
Prybars, Hammers, chisels, Putty Knives
Flat tipped shovel to remove foam, Old Carpenters Saw (The Old “Fox Hole” Army Surplus Shovels
work well)
Circular Saw
Sawzall
Dremel Tool
Multi Tool
Router
Drill
Random Orbit Sander
Rasps, Files
4 1/2" or 7” Grinder with Backup Pad and 24 grit resin coated sanding discs
Masking Tape
Shop Vac for dust control or Dust Collector if you're fortunate enough to have one. (Get the internal
bags for the Vac)
It's good to create a Plastic Tent over the boat to contain the dust. There WILL be a LOT of it....A
LOT!!!!
Glassing and Wood Products
3-4 sheets 3/4" Arauco Ext. Grade Plywood(Any good quality External Use Plywood will work)
(Possibly some 1⁄2” and 1⁄4” for side panels and seat bases when and where needed”
15 -20 Gallons 435 Polyester Resin Or Epoxy
4 gals Cabosil
1 lbs 1/4" chopped strand fibers (not needed if using epoxy)
5 yds 1.5 oz CSM (not needed if using epoxy)
20 yds 1708 Biaxial Cloth (use 17oz biax fabric if using epoxy)
2 dozen 1 qt plastic mixing buckets and stir sticks
1 - 1/2" x 5" Fiberglass "Bubble" roller
2 dozen Short nap 6" nylon roller covers and trays
2 dozen 3" Chip Brushes (cut 1⁄2 the length of the bristles off)
5 Gallons of Acetone.
Tri-Sodium Phosphate (buy it at Lowe’s)
I recommend USComposites in Florida for all your glassing supplies.
 

gsh

Petty Officer 2nd Class
Joined
Jun 9, 2010
Messages
104
Well, here are the pictures of the transom.

That welded in angle aluminum in the second picture was the only thing keeping the motor from ripping the entire transom off. Most of the screws holding the aluminum sheet to the inside of the transom had rusted off completely and it was just the head left.

Now I get to clean it all up and prepare to cut some new marine grade plywood to replace the transom, floors and hatches.

The lesson here is, if the floor is bad, the transom is bad. Don't even bother questioning it, it's bad. Just count on replacing it.

Stay tuned!

Before Removal -5.jpgBefore Removal -6.jpgTransom Cap-3.jpgRemoved-1.jpg
 

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gsh

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I have a question for those that have worked with fiberglass before.

As you can see the old transom was some pretty crappy 1.5" unsealed plywood.

My current thought is to remake the transom and put at least one layer of fiberglass fabric on each side and use epoxy resin to not only seal the wood, but also add some extra strength.

My problem is the transom opening is exactly 1.5" wide and I was wondering how much thickness that one layer of fiberglass fabric was going to add to each side? Is it going to add 1/8"? More? Less?

Depending on how much thickness it's goin to add, I may have to use one 3/4" sheet of marine plywood and one 1/2" sheet to account for the added thickness of the fiberglass cloth and resin.
 

gsh

Petty Officer 2nd Class
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Jun 9, 2010
Messages
104
So I got the transom out and cleaned up a bit more of the boat. I noticed a lot of corrosion on the inner protective aluminum panel and on the inside of the back of the transom metal.

Inner Hull-1.jpg

Some of those pits are actually holes that go completely through. I marked those.


Transom-Marked.jpg

The inner protective panel is also pretty bad.

Inner Panel-1.jpg

So I have a few options.

1. I can get a piece of 1/4" aluminum sheet and place that against the outside to cover everything from the bottom transom holes to just below the transom cap and glue it in place with some Gluvit or silicone to keep the water out.

It would be something like this.

Full Cover Plate.jpg

The Pros are that it will cover all holes completely and will look clean. The Cons are that it would be heavy and I would have to drill a few extra holes through the transom to secure it at the top and side edges.

2. The next idea is to make a small reinforcing plate to place under the motor to add support and cover the holes right next to the motor. The other holes would be repaired in one of several ways I will discuss next.

It would look something like this.

Center Plate.jpg

The Pros are that I could reinforce the area that the motor would be pushing against and cover a few holes while I'm at it. It would also be lighter than my first option. The Cons are that I would have a lot of other holes to deal with.

The rest of the holes could be drilled out and filled with an aluminum rivet, left as it and filled with silicone before installing the transom wood (not my favorite idea), filled with something like Alumiweld or Muggy Rod or filled with JB Weld. Or, if I can convince the welding shop to do it, they might be able to weld the holes up.

I know what a rivet would be like and I kinda know what JB Weld would be like, but I have no experience with the Alumiweld or Muggy Rod.

https://www.muggyweld.com/product/super-alloy-5/

https://www.alumiweld.com/

I was also thinking about fulling any large divots on the inside of the transom with JB Weld just for a little extra strength before painting it.

I plan on painting everything above the chine and putting a coat of primer and paint on the inside of the transom before putting in the new, sealed wood transom.

So what are your opinions on it?
 

appleo

Petty Officer 1st Class
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Jul 19, 2012
Messages
388
Jumped on late sorry

1 Replace all hoses
2 Sincd you removed the foam might as well gluevit the rivets
3 Consider Advantec for your subfloor. google it I used it in 3 restorations
4 Stainless hardware only. ebay
5. Lots of posts on transom Strength comes from the plywood laminate layers.I coated mine with 5200 before dropping in
6. Run your wiring under floor in conduit or hose before laying floor
7. i have used carpet and nautolex for flooring coverings. Nautolex is nice.
8. Guys use pool noodles from
dolar store as replacement foam
9 no softwoods pine spruce trex interior plywood
10. imo any transom Al stiffener I would bolt outside not inside

Enjoy.
 

appleo

Petty Officer 1st Class
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Jul 19, 2012
Messages
388
Btw your original transom likely not 1/4 " aluminum.
Hence go thinner on any cover plate. maybe 1/16" imo

appleo
 

gsh

Petty Officer 2nd Class
Joined
Jun 9, 2010
Messages
104
Btw your original transom likely not 1/4 " aluminum.
Hence go thinner on any cover plate. maybe 1/16" imo

appleo

The old aluminum on the outside of the transom was dented due to the transom rotting and the previous owner screwing it up by ignoring the problem. So right where the bottom of the motor contacts the transom, there is a couple of nice dents. Once I get the dents sorted out I plan on covering the area directly under the motor with some 3/16" aluminum plate I picked up for $5 from a metal shop. It's going to be about 11" tall by 14" wide and it's just to help distribute the weight better. If it covers a few holes, that's a bonus.

Look at the bottom picture I posted and you'll get the idea.

For the inside of the transom I bought some 0.040" aluminum to replace the old piece that was in there. It's primarily there to seal the splashwell and run the splashwell drains into. The old piece measured 0.045", but I couldn't find any of that locally without buying an entire 4' x 10' sheet for $250. Instead I found a piece of scrap just a bit bigger than what I needed for only $25. The old piece has so many pinholes that it looked like a dirty screen door in the sunlight.

I just got done cutting out the new transom wood. It's 2 pieces of 3/4" marine plywood glued together. I'm going to seal it with epoxy and glue the new inner aluminum to it.

The pinholes and the larger pitting I'm planning on closing up with some Muggy Weld Super Alloy 5. Then I plan on coating the inside with some primer and Krylon.

As for the floor, I'm going to use 3/4" marine plywood sealed in epoxy and fiberglass on both sides. The floor will most likely be Tuff Coat or something similar rather than carpet.

Once I get the transom finished I plan on cutting all the wood for the rest of the boat before starting on the electrical work.

I already planned on routing everything through conduit, but only where the wiring had to go through the foam. Everyplace else will have the split plastic wiring protector over it. I can't go under the floor because the livewell prevents me from going all the way to the front. Instead the sides have plenty of room along the top where the old wiring went. That gets me around the livewell and keeps the wiring easier to get to for repairs or modifications.

I was also already planning on sealing the rivets with Gluvit just to be safe.
 
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