new member... recent 79 v20 cuddy purchase

That sounds good. Didnt think of using 5200. Ive been thinking a lot lately about fabricating a central drain system like newer vikings have. Its basically 1 1.5 inch length of waste hose run along the port and stbd gunwale, slightly downhill, leading to a through hull aft. You plumb anything you want to drain into the hose. Vikings use it for a/c discharge, bulge pump discharge, shower box discharge, etc. It would work great on our boats for the same reason. Plumb the rod holders and anything else you want in there, install a through hull, and never worry about it again. Ive also been think about building a hybrid self bailing deck/showerbox system where id tee off the self bailing drain hose, install a ball valve, and run it to a showerbox (a sealed box things can drain into with a bilge pump and float switch to pump it out. This way you can drain things low and pump it out to a through hull placed up high). It like to consolidate things and be able to seal the bailers for when my boat is sitting low in the water.
 
Do not go any higher than around 3 PSI, 20 PSI would blow your tank to bits. Pump her up and see if she holds. One possibility is the PO thought the tank was leaking when it was really just the fuel level sensor seal that went bad. When mine went out you would have thought the tank was cut in two so much fuel was able to pour out when accelerating.

If it does leak, as far as pulling the tank, a saws all run around the perimeter makes quick work of it. Wedge the chunks out with a nail puller or a wonder bar.

Personally I would stick with the premix setup vs, the oiler.
 
http://www.uscomposites.com/foam.html

They sell the foam you would be looking for. You would use a 4 LB foam underneath the tank and 2 LB on the sides. When I set my tank I used some blues styrofoam squares to get the tank at my ideal height and distance from the sides. Then used large clamps to keep the expanding from raising the tank as it expanded.
 
even 3 lbs could do serious damage to the tank, the boat, and possibly your body.. think about it that's 3 lbs of pressure for each square inch... if the tank were 50" x24"x 18" You would have 15,192 lbs of force at only 3 psi!

Places that pressure test fuel tanks use less than 1 psi often with the tank submerged to look for bubbles or have the tank in a special box that supports all sides and is strong enough to withstand the pressure

My advice is that you completely forget pressure testing it or having it tested.... just rip it out and put in a new tank n be done with it.
 
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just spoke with the previous owner yesterday... it was bypassed because the gas is a few years old and he didnt wanna clean it.. on to my next question. how do you thoroughly clean a tank with varnished gas?
 
First I'd try and pump out what's in there and see what it looks like. Who knows you might find a little water on the bottom with some gas you could run through your lawn mower on top. My Grady had 20 gal of gas in it, pre-mixed unfortunately, with a bunch of sediment in the bottom. I took all the gas out,put a little fresh gas in the bottom and sucked out the leftover sediment with my air powered brake bleeder. The gas in my tank was only a year old though.

I just went back and read that your tank was full of premixed gas. I guess your in the same boat as me. I'm just hanging onto my gas until May when my county,Essex, has a hazardous waste drop off day in May.
 
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tartuffe said:
When I tested my tank I tested at 3 psi. I personally wouldn't offer advice if I had not done the research. But don't take my word for it.

http://www.uscgboating.org/regulations/boatbuilder_s_handbook/fuel_standards_partq.aspx
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That test is for a NEW tank outside of a boat.... A 20-30 year old tank could have significant corrosion and could rupture at MUCH less pressure than a new one.

I wasn't intending to attack you... Just offering my own advice.... I too have a little experience with fuel tanks.

Either way it sounds like maybe his tank is ok.

BTW old gas can be easily burned 1 gallon at a time in an old coffee can
 
Assume the tank and everything below deck has been taken care of as good or worse as the easy to get to/easy to clean and maintain parts above deck.

Then go back and look at your first pictures in this thread.

Rotted fuel tanks are one of the common problems on V20's which were a massed produced vessel. Yours was built during the roaring economy of the Carter years.

Personally I wouldn't trust a 35-36 year old tank built by the lowest bidder and installed in a marine environment with questionable care from the previous owners.

I still think you got an awesome deal!
 
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A while back I discovered that my tank was leaking. I did wind up pulling it and replacing it with a new one. I purchased a new tank manufactured by http://sunshinemarinetanks.net/. I drew up a diagram with the exact measurements from the old tank and it was a perfect size replacement. Prior to installation I coated it with coal tar epoxy, the foam I bought from the place mentioned in a previous post. It was a struggle to get the tank out but once I got it figured out, with much help from the forum here, I now have such peace of mind knowing that I have a new tank under my feet. It was not expensive, doing all the work myself, and taking my time with it. I did not want to take any chances with a leaking fuel tank. Good luck and welcome home!:sun:
 
i only live a few miles from sp tanks in barnegat (http://www.sptanks.com/webdev/home.htm) so if i wanted any work done id end up calling them. my budget is pretty tight on this boat (26 year old dad trying to make ends meet) but i think im going to at least pull it and check for corrosion/fill it with water and see if it holds. maybe fill it with water and give it a few pumps with a bicycle tire inflator. if all checks out than maybe coat it with por-15 or something similar. if you arent familiar with por-15, i strongly suggest you check them out. im trying to make the boat as safe and reliable as possible without breaking the bank. i should have some time this weekend to pull the tank, rebuild the carbs, and check out all the wiring (ensure bilge pump operation, check gauges, etc.) so anticipate some pictures. thanks for all the help and opinions so far guys (and gals if so applies).
 
hello and welcome to the site I am fairly new myselfmy rig cost me twenty eight hundred so you did pretty good I got a real nice trailer brand new bimini topand a brand new Lawrence depth finder still got some work to do in mine but I'm excited about it
 
quite often the tank is destroyed in the process of removal.... I maintain that even on a tight budget, if you are going to go to the effort of removing, replace it...
ALSO filling with water is NOT a good test as gasoline being thinner will leak out of a tiny pinhole that water even under pressure will not
Found that out first hand
 
Thats good to know. Ill just try to clean it in the boat and see what happens. Worst case ill run off the little tank. I dont wanna open a $400+ can of worms. Damn boats.
 
RABBITFISH said:
A while back I discovered that my tank was leaking. I did wind up pulling it and replacing it with a new one. I purchased a new tank manufactured by http://sunshinemarinetanks.net/. I drew up a diagram with the exact measurements from the old tank and it was a perfect size replacement. Prior to installation I coated it with coal tar epoxy, the foam I bought from the place mentioned in a previous post. It was a struggle to get the tank out but once I got it figured out, with much help from the forum here, I now have such peace of mind knowing that I have a new tank under my feet. It was not expensive, doing all the work myself, and taking my time with it. I did not want to take any chances with a leaking fuel tank. Good luck and welcome home!:sun:
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Great link. What did you pay for your tank?
 
RABBITFISH said:
Yes here is the site where I got the foam from..http://www.uscomposites.com/foam.html
Great stuff, and it is the kind that does not absorb water..
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Rabbitfish, I'm sorry to have to tell you, but ALL foam will eventually absorb water... Open cell, closed cell, it makes no difference. These forums are filled with posts from guys that opened their decks because of soft spots, only to find that their stringers and under deck wood had rotted away... and in the process found out that the foam in their bilges was saturated with hundreds and hundreds of pounds of water. If you go to most foam manufacturers websites you'll see disclaimers in the fine print stating that their foam is not recommended for continuous immersion in water. In fact, this quote is from the site you posted the link to:
This foam is approximately 95-98% closed cell which resists absorbing water, however continuous water submersion can eventually lead to loss of buoyancy over a period of years.
Click to expand...
Now granted, it may take several years for the foam to start absorbing the water, but eventually all foam will. The ONLY cure to keep foam from absorbing water is to not let it get wet in the first place. Seal all deck hatches, fix all cracks and holes in rod racks, seal and cap all rod holders... in short, do all you can to keep water out of your hull. Your deck, stringers, transom, foam, tank and wallet will thank you for it in the long run. :head:
 
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