Fuel tank replacement help

crsavage1 · #1 08-10-2018, 09:55 PM

So needing to replace the fuel tank in my 1968 19ft and have a few questions. Where the tank was mounted is full of about 3-5 inches of water in a supposedly sealed area. Is this probably from just intrusion through the console or something else? Also it was just on top of the plastic mats in the picture which I assume is not standard?

Any recommendations on where to source a new tank? Also a little concerned about other parts of the floor, is it probably better to replace it before going back with the new tank etc? It appears as though the floor is some sort of sandwiched foam product but not quite divinycell...hard to tell.

Below are the pictures of where the tank was and the tank itself. Any insight and advice would be very helpful.

uncleboo · #2 08-11-2018, 10:03 AM

When I cut the floor out of my 18 I was thinking I had some type of foam as well but it was just balsa.

crsavage1 · #3 08-11-2018, 12:55 PM

I included some pictures of the floor material. It seems like foam sandwiched between fiberglass. While the site was down I posted over on THT as well and they weren’t sure what it was either. The floor seems spongy in places and it makes me wonder if the structure underneath is either missing or too far apart. I am trying to understand what the floor support should look like.

Also, not sure what to replace the floor with should I get to that. Marine ply or something like carbon core sandwiched with fiberglass? One camp certainly thinks the composites are better while others think properly sealed ply is just fine too.

I am concerned about the weight overall but unsure if it really is that significant. I need to work out the CG calculation using the worksheet in earlier threads to make sure I put the tank and the console back in the best place because mine has a bracket.

In short....too much to do and it is making my brain spin a little.

Vezo, Part II · #4 08-11-2018, 01:11 PM

Those pics are deceiving. Is this a CC? I thought all fuel tanks were above deck and located in the console. You have what appears to be a fiberglass molded “fuel hold” similar to my 79 MA? But yours also seems to not have a floor. Is the bottom side of your tank bellied to contour the shape of the hull?

Cannot beat Sunshine Tanks Of South Florida, who built almost all SeaCraft tanks of that era, and may still have the plans. Also RDS Of Perry, Florida is more than qualified. Just call for two quotes. Some use the old adage of “ten bucks/gallon”, and I just took it in the ARSE, believing the new tariffs doubled the price!?! Please learn from my mistakes!

Vezo

crsavage1 · #5 08-11-2018, 06:48 PM

Well this boat is a bit of a mystery. It’s a 1968 and some thought it was originally a bow rider that had been converted while others thought it was just an early CC. Whatever the case, something is different as today while I was cleaning up I noticed that the cap appeared to be different sizes between port and aft. I thought it was just an illusion so I put a tape measure to it and sure enough...not the same. Not sure how that can be?

Thanks for the tips on sourcing the fuel tank, and yes, the tank is contoured to the bottom. No drains though so it was full of water and I cleaned it up. Same with the fish box..no drains and retains water.

Vezo, my apologies but what did you mean by the tariffs? Your tank was not roughly “10 a gallon”?

Any insight welcome...the mystery widens a bit...

Vezo, Part II · #6 08-11-2018, 06:49 PM

You’re going to get a lot more help here than “over there”. Let’s start by what year and model you have because you’re user name is also the name of an older model CSC.

Vezo, Part II

Vezo, Part II · #7 08-11-2018, 06:50 PM

Sorry, site did not update quick enough. 70 gallon tank, roughly $700.

crsavage1 · #8 08-11-2018, 10:31 PM

Just so happens my last name is Savage although I probably should have bought a Savage! Mine is a 1968 but as I mentioned there seems to be some debate as to whether it started life as a bow rider or as an early CC. There are some previous threads about my boat where its history was discussed to some degree. I don’t think there was any definitive answer, example of a thread is: http://www.classicseacraft.com/commu...625#post255625. There are a couple of others as well.

The cap does look original in some places, but the difference in size throw me off and doesn’t make sense. The cap in general seems off.

The bow does as well, the anchor locker area. I have not seen another CC like mine but that doesn’t mean much either.

I can take just about any picture to help, it has a bracket and I will need to do the CG calculations as I plan to repower as well and want to make sure I get the console and fuel tank to help balance the boat. Thanks for the help and advice, I can use as much as I can get.

crsavage1 · #9 08-18-2018, 06:30 PM

So I continued to remove the remaining floor. A few questions though, it seems the sub structure is a bit off.

1. It looks like someone tried to pour foam into the corners in the stern but am unclear why? There are big blobs of foam which I seriously doubt would provide any floatation so unsure why they would do that. Parts of the stringers weren’t raised so the floor was sort of floating.

2. I am unsure whether the tab I left in for the new floor is adequate enough to support the new floor? The material is questionable and pretty spongy so won’t that make the new floor spongy near the gunwales? If not, I am unsure of what the right way is to correct this situation? Cut the tab out to the edge? If I do that, doesn’t the liner sit on the floor? I am confused....

3. I added a picture of where it appears some of the stringers were cut out? I added a picture where I marked in red where it appears it is missing. Again, what is the best way to correct that?

4. Next step would seem to be grinding everything back out. A lot of the existing fiberglass looks bad and doesn’t seem it was laid up correctly. Is that the best step or do I need to be concerned about the tabbing for the new floor?

Any suggestions or advice welcome!

crsavage1 · #10 08-20-2018, 06:45 PM

Any thoughts? Additionally I was considering a stock fuel tank from RDS rather than a custom one. The stock ones will fit fine but curious if there is a specific reason to have one custom made? I know the bottom of the belly section is wider than the one that came out of mine, but I was going to lay down a composite bed for the tank to sit on anyhow for air circulation and to allow the areas to drain to the bilge so I can essentially raise the tank and still have it fit. Anyone have experience with one of the pre-made RDS tanks? They are constructed of .90 5052 rather than .125 5052 which was one of the only differences I noted. Thanks for any insight...