Gas Tank Replacement - Osprey 245

[Bergertime]

All,

Well I am sad to say that I had to drop her off for some major surgery earlier this week.  Background - I have had a fuel leak which just started as odor (a month or two ago) to full blown raw fuel dripping out of the plug hole.  I checked all the connections and my sender is new so I came to the sad realization that it was my tank.  As I don't have the time nor inclination do tackle this myself I took it to a guy here in Tampa that I trust and the transplant has started.  I have some pictures to post on the work so far with the old tank going to fabricator today.  It's worthy to note that the leak was on the very bottom of the tank where it made contact with the very wet and rotten base.  For those of you that are interested please feel free to post ?s.  Enjoy the morbid    picks.

[seabob4]

That's my old drunk redneck buddy Tim Phipps, for ya.  He's the one who installed that tank.  The tank rubber on the angled flats is fine, but I see no evidence of tank rubber having been on the bottom of the tank, at least 2 strips lengthwise to keep the bottom from being in contact with the floor of the tank compartment.

[Capt. Bob]

It's worthy to note that the leak was on the very bottom of the tank where it made contact with the very wet and rotten base.

First,
Welcome to the fraternity of the Brotherhood of Tank Replacement Installers Society.

Next,
I've never seen a tank that didn't leak on the bottom on this Forum. Water trapped between the tank and floor. Very common.

You have checked the tank floor (yes it looks bad but) for rot? Most all coffins have that black color and it will clean up very nicely with mineral spirits.

Let me ask this. Take a look at the forward bulkhead in the tank compartment.
Is there a drain pipe at the bottom along the keel?
Is there a space (of course) between the tank floor and the keel?
Lastly, is there a drain between the rear bulkhead and the bilge?

While it appears that I'm stating the obvious, I always like to get help to support my conclusions.

Thanks and good luck with the new install.

[Bergertime]

Bob,

Yes, there is a short tube b/t the front bulkhead and another through the rear of the tank compartment.  I think the problem started when the base mounting material that supports the tank gave way and got wet from the deck or water running underneath.  The rest.. Well that's is history.

B

[Capt. Bob]

Yep,
I'm not a fan of that system. Does your Osprey have a forward bilge pump?
My WAC does and I sealed the forward and aft bulkheads with expanding neoprene plugs and 4000 UV sealer.

Why?
Well I'm a follower of the dry tank coffin cult. Water finds it's way into the front bilge on my WAC so now when that happens, it stays there and is removed with the forward pump. Same for the rear bilge. Water trapped there, stays there and is removed via the pump or plug removal while on the trailer. The factory design uses the keel to move water forward to aft but while underway it also allows it the traverse stern to bow. Add to that any water that can penetrate the tank hatch (if it exists) and you can get water trapped or at the very least, sloshed up between the tank bottom and the support.

I found water/fuel in my WAC coffin and the tank itself indicated that there was a fair amount of water present in the coffin at times.

Note "waterline" on original tank.

[Bergertime]

Bob - Wow!  Thats quite a water line on that tank.  I don't have a forward bilge pump so yes, the water that made it's way into the anchor locker or storage locker forward of the seat was making it's way back to the tank compartment.  I know from previous attempts to wash out the gas smell that the water was moving all the way back to the bilge from the front and out the plug hole, I just was not aware the level or rot and decay that sat in the middle under the tank.  To avoid having to de-rig the console and rip off the t-top we elected to shorten the new tank and compartment by approx 18 inches and raise the top of the tank top by 1.  Based on some prelim calculations I will net an approximately 20 gal of capacity loss (I have to get the exact capacity from the fabricator)... not a biggie and preferable to a total de-rig.  We also discussed some better piping and mounting that would support more effective draining of the tank compartment.  

Btw: CL Mattson here in Tampa is making my new tank.  So far they seem like a class "A" operation.  I spoke to owner Colin on the phone for quite some time and also visited his shop to look at some of his other work and tanks he has made.  From all indications and many recommendations he is the "go-to" guy around here plus a 4-5 business day turn-around.

PS.  I have a WEMA sender in my old tank that is approx. 1 year new that I am going to pull out.  I will give it to anyone who wants it's..  It fits the orig 141 gallon AS tank.  I will look up the exact measurement or measure the length of the sender and post.  The tank height adjustment for the new tank will not allow me to use the sender plus it comes with one installed.

http://www.customaluminumfueltanksfl.com

More to follow..

B

[Bergertime]

New tank completed pressure testing today and ready for installation.  It was a 3 day turnaround from spec to completion.  I lost approx 15 gallons due to the re-size (141g to 125g).  





Tight lines..

B

[Capt. Bob]

Looks good (don't they all when new).    

Big question will now be the mounting method.

Good luck.

[flounderpounder225]

Bob - Wow!  Thats quite a water line on that tank.  I don't have a forward bilge pump so yes, the water that made it's way into the anchor locker or storage locker forward of the seat was making it's way back to the tank compartment.  I know from previous attempts to wash out the gas smell that the water was moving all the way back to the bilge from the front and out the plug hole, I just was not aware the level or rot and decay that sat in the middle under the tank.  To avoid having to de-rig the console and rip off the t-top we elected to shorten the new tank and compartment by approx 18 inches and raise the top of the tank top by 3.  Based on some prelim calculations I will net an approximately 20 gal of capacity loss (I have to get the exact capacity from the fabricator)... not a biggie and preferable to a total de-rig.  We also discussed some better piping and mounting that would support more effective draining of the tank compartment.  

Btw: CL Mattson here in Tampa is making my new tank.  So far they seem like a class "A" operation.  I spoke to owner Colin on the phone for quite some time and also visited his shop to look at some of his other work and tanks he has made.  From all indications and many recommendations he is the "go-to" guy around here plus a 4-5 business day turn-around.

PS.  I have a WEMA sender in my old tank that is approx. 1 year new that I am going to pull out.  I will give it to anyone who wants it's..  It fits the orig 141 gallon AS tank.  I will look up the exact measurement or measure the length of the sender and post.  The tank height adjustment for the new tank will not allow me to use the sender plus it comes with one installed.

http://www.customaluminumfueltanksfl.com

More to follow..

B

Bruce
I think that is a great idea to mod the tank size instead of tearing the CC off.  Why raise the height of the tank 3 "  and can you post the exact measurements my day is coming I'm sure...  Thanks

[wingtime]

Wow BUMMER.

It is interesting to see the deck core material is different in the coffin lid cut out area than the rest of the surrounding deck.  I have a feeling why we are seeing Ospreys turning up with bad decks and few Explorers...  It's the screws.... look at all the mounting screw holes in that deck.  My Explorer on the other hand has ZERO.  No matter how well you seal those screws up in time they will loosen and leak.  So if you have a solid deck on your Osprey I'd suggest you rebed all your screws that penetrate the deck.

Nice looking tank.  I can't wait to see the finished pics.

Bob,  The stringer/coffin area.... looks different than the Explorers I have seen pics of under construction... I thought they all had a premolded stringer grid that was bonded into the hull.

[Bergertime]

Sure.. I will post the new measurements.  There was over four inches of room b/t the floor and the top of the tank so we decided to raise the overall height of the tank to make up for some of the lost capacity due to shortening.  More pics to follow.

BTW- The PO put more holes in the deck than swiss cheese plus I knew the deck had some soft spots going into the sale.  I was planning on doing a new floor in a year or two and I would have replaced the tank in parallel but the leak moved my timeline foward.  After the work is done it's really going to be a 2/3 deck replacement and I will likely have the front done next year sometime so that the finish matches.  For now she will look a little uneven but I will be glad to get back out on the water...  I am dying over here!!

B

[Capt. Bob]

Bob,  The stringer/coffin area.... looks different than the Explorers I have seen pics of under construction... I thought they all had a premolded stringer grid that was bonded into the hull.

Figure your talkin' at SB but the stringer grid and tank floor look just like my 91 WAC.

Like this I would guess.

[floridamisser52]

So,does only the newer AS have composite stringers? Thanks.

[seabob4]

A lot has to do with when the boat was built.  Model year changeovers are typically in the July timeframe, so boats built in August of '97, for instance, would be sold as a '98.  Changes also have a lot to do with how significant a change it was, and how quick the big boys wanted it implemented.  Just as we have seen in older Aquasports in regards to 2 boats of the same model, from the same year, being quite a bit different below decks, well, obviously, that practice carried over even after Genmar took the reins...

A perfect example, from my PL days.  Johnny Walker (the Pres) went to the Miami show, Southco had just come out with their compression hatch pulls...and he fell in love with them.  Gets back to the pant, decides, RIGHT NOW, all boats 26' and above (my boats) will get these latches.  I get them all speced in, the guys in the plant start installing them...on half the years models!!  The earlier part of '07, those models got the old Orcas twist-lock pulls.  Same boats, same year, totally different hardware.  We had a big binder that we recorded any significant changes in, that book MAY have made it up to the Fountain plant when PL moved...but I doubt it....

Just like all the AS stuff that was left behind when the Sarasota plant was shut down...

[wingtime]

The reason I ask is my bilge/ stringers have a finished gel coated surface to them....  nice and smooth like they came out of a mold.