1978 Mark Twain V-Sonic Restoration

[JonathanW]

A friend and I recently obtained a '78 V-Sonic from a guy for $200. He bought it because he needed the trailer from it, and that's why he sold it so cheap.

Here are the pictures I saw before I went and looked at it and bought it:

It has a 165HP Mercruiser in it (the 4.3L inline 6), and a Mercruiser Alpha One Gen I outdrive.

So I went to look at the boat, and was very pleased with it, so I bought it.

From what I could tell, the engine was in very good shape, as was the floor. The interior, not so much, and the skeg has a big chunk out of it.

So once I got home with it, I took the pressure washer to her and she had started looking better already.

 

[JonathanW]

Re: 1978 Mark Twain V-Sonic Restoration

So after a quick clean up, and rip out of the rotten, weathered interior, I moved on to the engine.

This is my interior rip out:

 

[JonathanW]

Re: 1978 Mark Twain V-Sonic Restoration

So when I was done with this, I needed a little bit of a change so I started on the engine.
First we went though the mess of wiring, and tried to get a general idea of what was going on, and we got it wired up enough that we could hotwire it (someone ripped out the ignition switch) to see if she would turn over.

Well the starter would tick but she just wouldn't turn over, so out comes the crowbar. So after spraying some WD-40 in the plug holes, we start trying to pry her free, at which point we couldn't get a grip to spin her over. Once we finally got a grip, it didn't take much and she started spinning freely, so back to the ignition we go. We tried and tried with no luck to get her to turn over on her own, by helping spin it as we tried to engage the start, and we finally gave up. So off comes the starter. I didn't get pictures of it, but it was in horrible shape, all rusted up, the rubber over the magnets was half rotted, etc. I had little hope, but I tried to clean it up with some diesel fuel, but I just couldn't get it to work.

So I got the new started, and we put it on. Again she just wouldn't spin over. We finally came to the conclusion on it that the battery we were using wouldn't hold enough of a charge, so we hook up my truck and hook up the jumper cables.

Finally we make progress and she turns over all by herself. So we throw the plugs in and see if we can get her to sputter or anything. While I'm up in the front hotwiring it, my uncle is in the back messing with the carb while she's spinning. After much spinning, there's a loud boom and white smoke so thick that I couldn't see my uncle through it, and then we realize the oil dipstick is no longer anywhere to be found.

After we finally find the dipstick sitting on top of the windshield wiper of my truck, we decide to test the compression on the cylinders. Cylinders 1-5 are flawless, with great compression, but number 6 read 0 across the board.

So we take her all apart, and sure enough, there's what looks like a bullet hole right in the center of the sixth piston.

 

[JonathanW]

Re: 1978 Mark Twain V-Sonic Restoration

So I order the parts to go ahead and fully rebuild her, and we start taking the engine out.

The rest of the engine was in pristine condition, and somehow the sixth cylinder walls were in perfect shape. I still can't figure how that hole got there.

So at this point since I have to wait to get the parts for the engine, I decide to go ahead and rip of the floor. The plywood was very solid, but the beams underneath, not so much. They all had some rotton spots, so of course we now have a bigger project than originally planned.

Now I embark upon the great task of cleaning the puppy out and getting her ready for new stringers.

I am currently 2/3 of the way done with the stringers, and have not started re-assembling the engine.

I will post some more pics tomorrow when I take some more.

This is my first boat restoration and so far it is going very well.

Oh yeah, I have been considering turning her into a center console, but I'm not sure how exactly it would work out so any opinions, tips, pointers, and "that's a bad idea" comments with details would be much appreciated :redface:

 

[mattpyle]

Re: 1978 Mark Twain V-Sonic Restoration

Looks like you got a good deal! However, I'd drill some holes in that floor and check it. I'd bet it's not looking so good in there. If there's leaves down in the floor, you can guarantee water has been in there as well.

 

[JonathanW]

Re: 1978 Mark Twain V-Sonic Restoration

Looks like you got a good deal! However, I'd drill some holes in that floor and check it. I'd bet it's not looking so good in there. If there's leaves down in the floor, you can guarantee water has been in there as well.

I updated the post before you saw it I guess. I'm replacing the floor and stringers, as they were rotton

Oh yeah, currently I am $700 in including the boat, and trailer, and everything I've purchased for it.

 

[JonathanW]

Re: 1978 Mark Twain V-Sonic Restoration

Anyone?