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KerrLake
12-21-2008, 07:46 PM
Merry Christmas to all. It looks like my Christmas present to myself is a new gas tank for my 86 z25. I read a post by Donzigo that said he had to cut his tank into pieces to remove it. I'm trying to figure out the safest way to cut the tank out. I can clean the inside of the tank with no problem. What about the gas in the foam underneath? Any suggestions?
Brian

BlownCrewCab
12-21-2008, 07:57 PM
You'll be removing the foam also. If you can, start cutting the tank with an air powered tool, then when you have the top of the tank off, or a huge hole in it you can switch to an electric like a sawzall and cut the tank into small enough pieces to peel off the foam. I don't like to start with an electric tool cause once you open the tank enough the rush of fumes can ignite. once it's vented enough it won't.

Madcow
12-22-2008, 10:25 AM
If you have to cut the tank to remove it how are you going to get the new one in? As to removing the foam I have found using a sawsall with a long blade does a nice job od obliterating all the foam on the sides, then if you are lucky you can jst pry the tank from the bottom foam.

KerrLake
12-22-2008, 07:34 PM
I read in a post by Donzigo that the tank will not come out without lifting the deck. If I understood his post correctly, he had a new tank made that would fit through the opening, just a little smaller than the original. If you look closely at the picture above, the tank continues underneath the floor to the cabin door. I would thinK I could fit a 50 gallon tank.

KerrLake
12-22-2008, 07:37 PM
Does aluminum spark when you cut it?

BlownCrewCab
12-22-2008, 08:52 PM
No aluminum doesn't spark when you cut it. It's the sparks taking place inside the electric motor (Like a sawzall, or grinder) that will ignite the source if theres enough of it. Doesn't allways happen, But Can Happen.

Donzigo
12-27-2008, 02:28 AM
You will end up with a 50 gallon tank. I did cut my tank w a sawsall. Put JOY in the tank to counteract the fuel fumes.

BigGrizzly
12-27-2008, 10:38 AM
CO2 works too, even exhaust from a car works well to. I also have an air sawszala, I have no idea why I bough it, too long ago

MOP
12-27-2008, 02:09 PM
OK I read where the tank will not come out with lifting the deck, purge it well with a good flush of soapy water full to the top then siphon it out. I was a fuel cell mech in the USAF, I had to crawl inside B52 wing tanks which not only scared the Krap out of me but gave me deep respect for possible explosions!

The post below is for those pulling tanks that will come out unobstructed!

I did not read any of the other posts, cutting the tank is very dangerous. I was a boat mech for over 30 years and changed quite a few foamed in tanks, I never risked cutting one my life is mine to keep!!!!!!!! Use a long blade to cut the foam around the tank, then remove the sending unit. Get a steel bar about a foot long, take 1/2" line and make three loops around the bar this will give you a good attaching point to hook a "Come Along" to find a good over head place to hook to and crank it up, about the time the boat starts to lift the tank will come loose!

A P.S. put the bar long ways not across the tank, as you pull up the tank top will bow pulling the walls away from the stringers!!!

Phil

HIGH LIFE
12-27-2008, 04:20 PM
I've taken several tanks out, I use an electric chain saw, after clearing the tank of gas and fumes. HIGH LIFE

mattyboy
12-27-2008, 10:46 PM
OK I read where the tank will not come out with lifting the deck, purge it well with a good flush of soapy water full to the top then siphon it out. I was a fuel cell mech in the USAF, I had to crawl inside B52 wing tanks which not only scared the Krap out of me but gave me deep respect for possible explosions!

The post below is for those pulling tanks that will come out unobstructed!

I did not read any of the other posts, cutting the tank is very dangerous. I was a boat mech for over 30 years and changed quite a few foamed in tanks, I never risked cutting one my life is mine to keep!!!!!!!! Use a long blade to cut the foam around the tank, then remove the sending unit. Get a steel bar about a foot long, take 1/2" line and make three loops around the bar this will give you a good attaching point to hook a "Come Along" to find a good over head place to hook to and crank it up, about the time the boat starts to lift the tank will come loose!

A P.S. put the bar long ways not across the tank, as you pull up the tank top will bow pulling the walls away from the stringers!!!

Phil


Phil ,
with that much know how and time in the business perhaps you can expound on the fuel tank job you did on your classic and why you decided not to lift your deck?

MOP
12-28-2008, 12:13 AM
Phil ,
with that much know how and time in the business perhaps you can expound on the fuel tank job you did on your classic and why you decided not to lift your deck?

Well following some advice from Geo about getting weight aft, I was looking at what to move where. Batteries and a few other minor items did not add up to much, so the fuel tank idea came into play. Though my stock tank was fine I decided to go with an aft tank for weight transfer. The stock tank is about 400 lbs full, my 40 gal aft tank is about 300 lbs full. That made for a really good shift aft, was easy just remove one bulkhead and slide it in from the engine compartment. I revamped the battery box as it was useless before, now it's decent storage. I put a dual battery setup in the engine compartment. The floor locker was removed the deck repaired, the tank was slid into place from the engine compartment chocked in place. Then two bulkheads aft of the tank were installed, once done the tank was foamed in and the deck hatch area glassed. It made absolutely no sense pulling the boat apart to pull a good tank that I had no intention of using, well as some know I have used the stock tank a few times. The boat needs less trim at speed and has -0- porpoising using the aft tank, anything more then 1/4 in the stock front tank the boat goes back to porpoising and and loses a couple of mph. Tells me Geo's advice was spot on!! May be moving another 100+ back aft this coming spring to see what that does!

KerrLake
12-29-2008, 01:22 PM
I'm worried about gas and fumes in the foam. Any safety suggestions?

BigGrizzly
12-29-2008, 01:32 PM
Not unless you light it with a tourch.

KerrLake
12-29-2008, 01:49 PM
Not unless you light it with a tourch.

The tank was leaking from the bottom. No worries there?

penbroke
12-29-2008, 07:14 PM
I've been scared exactly twice in my Donzi. Once was when I was removing the gas soaked foam from the hull after the tank was out. The foam was soaked to the point of squirting when squeezed. This was after I let it sit for a few days to dry out once the tank was gone

I brought the boat outside, kept myself upwind and had fire extinguishers at arms reach in every direction.

This should not be taken lightly. Be very carefull...


Frank

KerrLake
03-10-2009, 09:33 PM
I finally took the gas tank out last week. I have been going at it in stages to give it a good chance to air out fumes. After I got all of the fuel out I let the tank sit for a couple weeks. I could still smell fumes so I put water in the tank and pumped it out again. I let it sit a few days again. Next I took a hand saw and cut the tank open starting at the sending unit hole. I got it where I could fit my hand in the bottom to wipe up any liquid that was left. I let it sit for a couple more days. By this time I couldn't smell any fumes and went at it with my grinder with cutting disk. It took about 1 hour to get it out. There were 2 holes in the bottom of the tank, one in the very front and one in the rear. This process was pretty slow, but I didn't feel I was in danger doing it that way. All who have not changed their tank in older boats should look at these pictures and consider it. I'm glad I found it before it found me!

BUIZILLA
03-10-2009, 09:59 PM
we just removed a tank last week from a garage stored 20' Mako, year 2000, had 2 holes in it... couldn't believe it...

KerrLake
03-18-2009, 11:36 AM
Got this quote via email from the online quote form.





A fuel tank with the provided specifications would be 55.0 gallons and weigh 60.9 lbs. It will be made from .125 Aluminum and cost $577.00 each.

· Tank is manufactured out of 5052-H32 Aluminum Alloy.
· Terms are payment in full to issue drawings and initiate manufacture.
· Lead-time: 3-4 weeks after we receive full payment and drawing approval
· Tanks are quoted FOB Henderson, NC.
· Shipping is not included nor estimated by FMT. Tanks are shipped freight collect.
· This quote is based exclusively on the information contained on drawings. Revisions and/or variations from this information may invalidate this quote.
· Tanks are quoted with pickup (NPTF fitting welded), fill, vent, and electric sending unit.
· We no longer stock or purchase Wema or Rochester Twin-Site senders (visual gauges).
· To ensure the structural integrity and safety of our product, F.M.T. requires mounting information (via drawing, video, and/or written explanation). F.M.T. engineering will assist in advising acceptable mounting modes should you require it.
· FMT recommends tank to have a fully supported bottom with ¼” neoprene rubber strips separating tank with support, and tank to be strapped or bracketed down.
· Tank is not designed for high performance use (application 55 MPH or greater)
· Quote valid for 30 days.





The factory is closed for the week due to our great economy. It's hard to believe, but FMT has a factory here in Henderson. I will go by and talk to someone on Mon. In the meantime, I know there is a big discussion on foaming in the tank. It sounds like FMT recommends bracketing the tank sitting on neoprene. I can have the tank primed for $50 or epoxy coated for $200. Tank is not designed for high performance use??


Any thoughts?

donzi2287
03-18-2009, 06:37 PM
I just changed my tank a month ago in my 22 classic. I live in the Keys. He charged me 600.00 and it was done in 3 days. I zinc chromate and painted it myself. I figured it lasted 22 years, and the paint will buy me a few more.!!!! If you want his number, pm me and I'll give it to you. It is better than the factory. Made in the U.S.A too. :yes:

Donzigo
03-20-2009, 08:22 AM
There is a craftsman here in St. Pete that made my fuel tank and a few more form people on the registry who has called him. The going price is about $10 per gallon. He uses stainless steel valves and always paints the tanks. I had him put the corners flanges and sat it on neoprene just as your guy said. it works great and it allows the water to flow back tothe engine room and out of ht eboat. Yeah, I know it's not the way the factory does it; but, they make boats for the most novice boat owner and they have to mkae the cavity where it doesn't drain. I will oen this boat until I die; so, I did it my way. The race boats do it that way too. I think a dry tank is always the way to go.

I had to have the fiberglass cut to get the Z-25 tank back in the boat. Then, he re-attached the fiberglass to the floor and refinished it and it came out great.

Send some more pictures of the tank finished and the re-install. I kept your pictures for future reference.

I always tell people on the registry that if your tank is over 10 years old, it needs to be evaluated, IMHO.

Richard
727-709-2918

Greg Guimond
12-19-2009, 02:16 PM
Has anyone had a tank made recently for a 16 ?

silverghost
12-19-2009, 02:40 PM
An old trick used to safely cut-up old boat gas-tanks in place safely to avoid sparks & explosions when cutting & sawing .
1) drop chunks of Dry-Ice (frozen CO2) into the tank fill or gauge sender port.
Use gloves to avoid freeze burns.
If you can't find Dry-Ice use a CO2 fire extinguisher with a hose connected to the tank.
or a CO2 welding gas bottle.
Pre-Fill the tank completely with CO2 gas.
The idea is to have the CO2 displace all of the gasoline fumes.
This method is used in the removal of large in-ground fuel tanks at gas stations & inground heating fuel tank installations.
My family also uses this method at their NE Phila airport based Jet Center Aircraft service facility here in NE Pilly.
They are working on multi-million $ private jet wing tanks all the time.
The saturated expanding foam is another problem ?