samzerelli's 1649 flat bottom overhaul

[samzerelli]

I bought a severely neglected 1649 Grumman flat bottom jon boat with a 1985 20hp Evinrude outboard and diamond plate floors. The boat used to sit in the water at the marina 24/7, so the motor housing and the boat are severely pitted.

I have been working on the boat for a few weeks. I decided to make this thread to keep track of and share the progress. I'll add some photos to get everyone up to speed.

Here are before pictures:

[samzerelli]

I removed the diamond plate floors by drilling out all the pop rivets. I then took the boat to my welder/outboard mechanic to have the following done:

- change the motor oil
- replace water pump impeller
- replace transom wood
- fix broken floor braces and make a few misc weld repairs
- added a piece of plate metal to re-enforce the front "deck"

The transom wood is completely enclosed by metal. He was able to just remove the bottom transom support brace and bend it up enough to get a new piece of marine plywood in there without having to cut it completely open.

Also, he found that although the motor is extremely ugly, it runs like a champ and seems to have low hours on it.

[samzerelli]

The next problem to address is the bottom of the boat. All of the rivets had some sort of flexible silicone sealant on them, possible 5200. There are no leaks, but this doesn't look kosher at all.

[samzerelli]

After peeling off all the sealant, I found that all 200+ rivets had J-B Weld on them. Some of the J-B Weld was in good shape, but others were missing chunks and cracked, etc. A leak test found 6 leaky rivets. Two of the rivets are actually missing and have been welded shut, both of which have a hole in the middle that is leaking.

I decided to remove all the J-B Weld from the rivets. I was able to do this in a matter of about 4 hours by using a propane torch. I made a video to show how well the torch worked to remove the J-B Weld.

[youtube]hsl7wwbd6K0[/youtube]

[samzerelli]

All the J-B Weld is removed and I'm now stripping the paint using Jasco paint stripper and a wire brush/wire wheel on my drill. Once I'm finished stripping the bottom, I will do another leak test to see how many rivets need replaced.

Here is round one of stripping the bottom:



This thread is now up to date with my progress so far.

[samzerelli]

Once I'm done stripping paint off the bottom, my next step will be to take care of three or four rivets that have been welded shut. Unfortunately the welds have holes in them now so they are leaking. I am going to grind off the welds and replace the rivets. As you can see, I have already ground off one of the welds.

[fool4fish1226]

Keep it comin Looking good so far

[Gramps50]

Keep on working and keep uploading pictures and posting progress. Looking good so far

[samzerelli]

After about 30 man-hours, I have the outside of the boat all prepped for paint.



I replaced about 14 rivets with these 1/4" closed-end aluminum/stainless mandrel blind rivets from Jay-Cee and got everything water tight. I used the instructions in this video:

[youtube]L0MA1-5NXjs[/youtube]

I then decided to apply J-B Weld to all of the 200+ rivets that are below the water line for a little extra insurance.




Next steps are to finish stripping the inside of the boat and then paint. After that I plan to reinstall the diamond plate floor in the rear of the boat and build a deck across the two benches in the front of the boat.

[TimRich]

Nice work! Looking forward to updates.

[samzerelli]

I pulled a bunch of dents out of the rub rail using a slide hammer. They didn't come out completely perfect, but I'm definitely satisfied.

Before:





After:




I'll grind off the burrs and finish it off with a little J-B Weld.

[samzerelli]

Day one of stripping the interior. This is a sucky task.

[acabtp]

what is going on with the single knee brace way off to the side?

[samzerelli]

what is going on with the single knee brace way off to the side?

I thought that was interesting too. That's the factory transom brace.

[bguy]

im doing some interior on my 16' monark it , your boat has plenty of potential .. i looking foward to your future post. what are your plans for the interior...?