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donzi2287
09-29-2008, 06:45 PM
Finally installed my 500 hp and put 5 hrs. on it and it ran awsome. This will be engine number 3 in only 15 total hours on the other two. Now, the tank is leaking....... This better be it. Anyway its an 87 22 classic. Any one take one out and replace? or is there a fix in place? Thank You.

mattyboy
09-29-2008, 06:56 PM
well let's take the opptimistic view, the gasket around the sending unit has been known to leak on occassion sometimes tightening the screws up might fix it ot a tear or break in the filler or vent hose??, then there is the pesimistic view and the deck must come off
do you know where it is leaking and the good news is you found leak before it found you

donzi2287
09-29-2008, 08:31 PM
i changed all the hoses and checked the sending unit. looks like the it is from the bottom o f the tank. i guess im cutting the floor. i'm not a happy camper. this really stinks after all the work on the motors! has any one taken the gas tank out for pointers?

penbroke
09-29-2008, 08:45 PM
Do a search on fuel tank replacement. No cutting required. Well, not much anyways...


Frank :lifeprese:
Put the saw down.

gcarter
09-29-2008, 09:19 PM
Don't cut the floor. It's so easy to remove the deck. Do it this winter.
I have several threads on changing tanks here. One on a Minx, one on an 18, and one on a 22.....well at least removing it so far...

donzi2287
09-29-2008, 09:39 PM
i want to boat now. I have been patient with the motors!! I live in the Keys. I think i am going to cut the floor just for less work overall. are there any other ideas besides that???????

MOP
09-29-2008, 10:06 PM
To replace the original tank you need to pull the deck, cutting the deck will turn into a bigger job that many times will not come worth a darn. Search for Georges thread, pulling the deck is not near as bad as it sounds.

Trueser
09-29-2008, 10:29 PM
Cutting the floor will be a big mistake. Pull the deck off would be less work.

donzi2287
09-29-2008, 10:48 PM
this still stinks. literally!!no easy fix, huh?

MOP
09-29-2008, 10:55 PM
Tale the time to look at some of the posts, with a little help I bet it can be done in 3-4 days.

mattyboy
09-30-2008, 03:59 AM
do a search on "paulo" i think that is his name he replaced a tank in a 22 and didn't lift the deck he sorta pivoted the deck like pacman and pulled it out thru the front just a tought you might want to beef up the structure in the back when the top is off if you have not done so already the 500 will take it toll over time

Morgan's Cloud
09-30-2008, 06:38 AM
this still stinks. literally!!no easy fix, huh?



Yes ........... TAKE THE DECK OFF ! ! :biggrin:

gcarter
09-30-2008, 06:39 AM
I think a person could change the tank in one day....but there would be a lot of preporation work before and after that day.
1) Completely unwire the dash, controls, and steering.
2) Remove all rails and joint screws.
3) Ditto lifting rings, shafts, and hatch.
4) Out of order here, first order tank and foam. Sand tank and prepare w/good grade of automotive epoxy primer. If you really care, follow with two coats of some "coal tar epoxy".
5) Figure out way to lift deck...it's not real heavy, maybe 400#, it can be done w/about four people but yo gotta go up a long way.
6) Do a dry run or two, completely figure it out.
7) Lift deck, remove old tank, it can be very hard or real easy.
8) Clean out tank recess, replace drain pipe under tank w/1" pvc pipe, it requires sawing 1 3/8" hole in both bulkheads. Epoxy in the new pipe. Original used double sided foam tape and was main source of water intrusion around tank.
9) Place tank, use my method of locating tank...read threads.
10) Mix foam and pour in.
11) Reverse procedure.

But in all honesty, take your time, do it right, make changes you want while it's apart. By all means, repair the cockpit floor. Most are doo-doo and really need reinforcing.

Your impatience is doing you no favors.

VetteLT193
09-30-2008, 07:20 AM
Here is a link to the pac man method. http://www.donzi.net/forums/showthread.php?t=23658&highlight=gas+tank+replacement

while you are in there you also might want to change the mounting hardware on the forward lifting ring considering you actually use it and they do rust out.

In my opinion your biggest problem/hassle is going to be the dash wiring. the rest of it is going to be easy for you...

mattyboy
09-30-2008, 10:44 AM
Not sure with a merc boat but all control cables and wiring we did on my volvo 16 was disconnected from the motor/ bottom half of the boat so when the deck lifted all the wiring was on the deck we didn't touch the dash

throttle cable removed from carb
shift cable removed from drive
tilt/trim harness removed from tilt motor
engine harness disconnected by pulling the plug apart and removing some wires from a wiring terminal
steering cable removed from yolk
and all misc wiring tabs and such lights were just pulled from the battery

my point is most of this stuff was thru the looms/hoops the factory put in under the deck so
why try to undo that

i know George is big on the foaming but IMO I think foam is not the way to go i mean this boat is just over 20 years old and the tank failed??? is it alum or a poly tank???? foam gives support I know but there are other ways to support the tank and bypassing the only outlet for moisture and water in the fuel compartment with the pipe and the foam will hold it in just doesn't sit right with me either but this is a old debate with plenty of reading

i do agree with him on take your time, when you have it apart there's other things that you can do or check to avoid more down time , do it right do it once

VetteLT193
09-30-2008, 01:51 PM
Who sells tanks besides RDS? RDS is up to nearly $1000 for the 22 tank.

gcarter
09-30-2008, 02:35 PM
Haven't priced a 22 tank yet, but I'll take your word for it.
They'll email you a drawing of the tank, maybe you can get another quote from it.
My philosphy is to thouroughly protect the aluminum tank from oxidation rather than find a different way of support. The original tank lasted 20 years w/o any protection, imagine how long it will last if it is thouroughly coated and protected. Like Matty says, there's lots of opinions and reading here. IMHO, foam support is superior to anything else.
It seems later boats (later than Matty's) have more stuff running through the pipe in the bilge. controls and steering goes through the hoops under the deck though, so maybe Matty's idea is superior.
Since I'm always doing more than just a tank, I always rip everything out.
Do you have any cockpit floor cracks?

donzi2287
09-30-2008, 03:16 PM
My boss asked how many beers will it take for the project. Just wanted to cost this deal out.

VetteLT193
09-30-2008, 04:08 PM
Haven't priced a 22 tank yet, but I'll take your word for it.
They'll email you a drawing of the tank, maybe you can get another quote from it.
My philosphy is to thouroughly protect the aluminum tank from oxidation rather than find a different way of support. The original tank lasted 20 years w/o any protection, imagine how long it will last if it is thouroughly coated and protected. Like Matty says, there's lots of opinions and reading here. IMHO, foam support is superior to anything else.
It seems later boats (later than Matty's) have more stuff running through the pipe in the bilge. controls and steering goes through the hoops under the deck though, so maybe Matty's idea is superior.
Since I'm always doing more than just a tank, I always rip everything out.
Do you have any cockpit floor cracks?

I'll answer the cracks question for him... yes, there are cracks in the rear of his floor. I think he said he's fixed them 2 times already prior to this time.

We talked earlier on the phone and part of the logic of cutting the floor out is to fix the cracks and re-support the whole thing. A good way of doing that with the rest of the deck still attached is not something that seems too easy.


My boss asked how many beers will it take for the project. Just wanted to cost this deal out.

A full keg might do it... I think we should take bets:nilly:

mattyboy
09-30-2008, 05:36 PM
try florida marine tanks they were an oem for donzi

www.floridamarinetanks.com

gcarter
09-30-2008, 08:34 PM
Here's where I started repairing the cockpit floor.
http://www.donzi.net/forums/showthread.php?t=50476&page=10
You'll see why they crack and one way to fix it.
I guess when Scot moved the site, many of the pictures were unfortunately deleted. I restored a lot of them. Maybe I'll do more of them later.

farmer tx
09-30-2008, 11:37 PM
I just ordered a 53 gal tank for a 22 classic hull from FMT. Not including shipping the price is $556.

Florida Marine Tanks, INC.
2219 Hollywood Blvd #101
Hollywood,FL. 33020-0000

Tel:305-620-9030

Item # FMT-53-DZ

.125 AL 5052-H32
1 7/8 Fill
5/8 Vent
Baffels-2
W-22"
L-76"
D-10 1/2"
Electric Sending Unit Included

mattyboy
10-01-2008, 07:42 AM
just a note the original 23 gallon 16 and 18 tank from FMT

is

FMT-23-DZ

p729lws
10-01-2008, 12:01 PM
Farmer TX, how old was the tank you replaced and what shape was it in? Seems like most tanks are lasting longer than this....

Dan

gcarter
10-01-2008, 02:57 PM
Farmer TX, how old was the tank you replaced and what shape was it in? Seems like most tanks are lasting longer than this....

Dan
Mine (built '87) was corroded 1/2 way through on the bottom.
Again, no primer or coating of any kind, and of course the drain pipe leaked at both ends.
I believe my replacement will be capable of lasting at leas twice as long.

mjw930
10-01-2008, 04:12 PM
You really need to pop off the deck, do the proper repair on the underside of the cockpit and make sure the area around the old tank is completely cleaned and repaired.

The cockpit floor isn't simply cracked, the rear section is delaminated and needs to be completely rebuilt. As I recall the tank foam was separated from the tank last January when I looked at the boat and I believe the port stringer that runs beside the tank needs to be looked at too, It sounded a bit hollow when I was tapping around.

I would take your time, pull the deck and make sure everything is looked at structurally. Do this repair once and do it right.

p729lws
10-01-2008, 05:27 PM
Mine (built '87) was corroded 1/2 way through on the bottom.
Again, no primer or coating of any kind, and of course the drain pipe leaked at both ends.
I believe my replacement will be capable of lasting at leas twice as long.

Is the drain pipe supposed to be sealed at each bulkhead to keep water out of the foam? So your tank hadn't failed, you were just replacing it as part of a renovation?

Has anyone else seen a failure of a tank from this time period?

Dan

gcarter
10-01-2008, 06:32 PM
Is the drain pipe supposed to be sealed at each bulkhead to keep water out of the foam? So your tank hadn't failed, you were just replacing it as part of a renovation?

Has anyone else seen a failure of a tank from this time period?

Dan
Dan, I would say there're hundreds of things Donzi should have done differently during that period. IMHO, the double sided tape used by Donzi was just the cheapest way there was to seal the pipe. You may remember from your own 22 that there's no indication of water on the top of the tank. It only gets dusty on top. In fact you don't see any water spots on the dust.
The water comes in around the pipe through the foam tape. Epoxying in the pipe eliminates probably 95% of any water entrance.
And don't even get me started about tabbing in the cockpit to the stringers, or the lack of any reinforcement of the cockpit floor.
I changed the tank on the Minx, and will on the TR because the aluminum on the bottom of the tank is only about .030 thick in places.

farmer tx
10-02-2008, 12:04 AM
The boat was built in 84 and spent all but the last 3 years at New Orleans in salt. It had minimal corrosion. The stringers and transom were completely rotted.

MOP
10-02-2008, 01:09 AM
Still the best mounting in a performance boat is foam, no movement/abrasion and it becomes an integral part of the hull. USCG Info below some good reading!

joseph m. hahnl
10-03-2008, 01:57 PM
this still stinks. literally!!no easy fix, huh?


"Yes" the quick fix to get through the season would be to put two small tanks in the bilge Or even secured in the ski locker.Accessibility would obviously be key as you would most likely have to take them out to fill.
Unless you rigged up a fill hose that adapted to the tank fill.

That a side ,Just because you put new stuff on doesn't mean those parts aren't leaking. Gravity can be very misleading. The chances that you didn't tighten something are highly more likely then an aluminum tank leaking. Next to the sending unit should be a sticker with the manufacture of the tank the material used and installation date.I would assume it was made by AFI Aluminum Fabrication Inc. When problems arise all ways double check what you have done. None of us are perfect. Well Except for that one guy."With the Red 18" :worthy:.

joe

penbroke
10-03-2008, 08:07 PM
...If the tank was foamed in and has been leaking the foam around it is soaked with gas. When I pulled the tank out of mine the tank had been empty and dry for at least 5 months and the deck had been off for more than a week. When I started to remove the foam it was soaked with gas to the point where I stopped and moved the boat out to the middle of the yard away from the building. It actually splashed me as I was cutting the foam...

Using another tank will not make anything safer if the foam is soaked. I won't even get into using portable tanks below decks...

Hopefully you problem is somewhere else as Joe suggested. My leak turned out to be at a sharp bend in the hose about a foot from the tank. The tank from 1966 was sound.


Frank
Fire Bad. Been there...

mattyboy
10-05-2008, 06:52 PM
i gotta tell you the pics of that alum tank scare me
roughly 20 years old and looks twice as bad as my 40 year old steel tank :eek:

donzi2287
10-05-2008, 11:56 PM
i gave up and decided to pull the deck off!!! everybody won!!! anyway hope to have it off this week and new one in by the next week. good news is the 500 hp screams and i can't wait to splash again!! thanks to everyone here