Split fuel tanks.

[eupa]

Voila un probem.

I have two 55 gallon fuel tanks encassed in the hull under the cabin which is
bolted to the hull , it can be removed - but it would mean a lot of work.
Have just finished my yearly over-haul and put a usb camera down to inspect the tanks. Unfortunately , it revealed each tank has a 5 cm crack at the top of the seam.( This must have been when I dropped 15 meters into a black hole... The tanks are side by side. Access will have to be by cutting a panel in the deck of about 50 x50 cms to weld the cacks.. Is there a prouduct that you can use that could chemically seal the leaks( I am reminded of Holts
rad weld)- or is there a another way ( a rubber bladder??). I do not want to really go about cutting the hull as this could weaken it??

any advice would be appreciated, and somebody coming up with a brilliant idea gets 4 bottles of Chilean cabernet sauvignon 2003. Santa Helena.

jonathan

[Pete7]

No chance, if they cracked its because they flexed or moved and split the seam. Glueing them up isn't going to hold. Tried the sealant stuff on a 110 landie fuel tank once. Didn't work and had to replace the tank.

Rip them out and get new ones made.

Think codders has the same problem, since you both get on really well perhaps you could do a job lot

Pete

[codprawn]

My problem is TOTALLY different!!! Eupa maybe you could use bag tanks - they work very well as long as you can get them in.

[jwalker]

Originally Posted by codprawn

Eupa maybe you could use bag tanks - they work very well as long as you can get them in.

Have you ever seen the back of a TIG weld? How long before they fret through?

I'm with Pete, there must have been flexing.

[Pete7]

Originally Posted by codprawn

My problem is TOTALLY different!!!

I do hope so, but how do you know you haven't looked inside the tank yet, but when you do you should see a vertical pipe going to the bottom of the tank. You could use an endescope to check were your fuel is leaking too.

55 gallons is a big fuel tank, and lets be honest BWM was know for high quality fabrications. Cheap tank perhaps or just lots of serious commerical work over the last 12 years means they are now at the end of there useful life.

Just replaced the ali water tank on Fly By for the same fault. 14 years old and at the end of its life, the ali corroded from the outside btw.

Pete

[eupa]

55 gallons is a big fuel tank, and lets be honest BWM was know for high quality fabrications. Cheap tank perhaps or just lots of serious commerical work over the last 12 years means they are now at the end of there useful life.

Thanks Pete 7. 55 gallons is not that big.. They are some 14 years old and Stainless. BWM dont make their own tanks- so I do not understand where you are coming from. Yessir, I do stress the bloody boat a bit- but that's whats ribbing all about.Unfortunately, I think you are right- tear them out and put some plastic ones in.

Jonathan

[codprawn]

Originally Posted by jwalker

Have you ever seen the back of a TIG weld? How long before they fret through?

I'm with Pete, there must have been flexing.

Depends how they are done - bloke who used to have a unit opposite mine was a great tig welder - did loads of work for the chemical and food industry. His welds were smooth as a babies bum inside so that glass liners could be slid into the pipes and valves. The way they do it is to fill with Argon first.

[codprawn]

Originally Posted by Pete7

I do hope so, but how do you know you haven't looked inside the tank yet, but when you do you should see a vertical pipe going to the bottom of the tank. You could use an endescope to check were your fuel is leaking too.


Pete

I haven't got a leak - grrrr..... I think the pickup pipe has moved or kinked - is this possible?

[Nos4r2]

Are the cracks in exactly the same places?

If they are I wouldn't weld up the crack, I'd patch it with a circular patch across the seam/crack so it shifts the stress points. Filling with argon works but the tanks will need flushing/washing out with detergent first.

[Bigmuz7]

Originally Posted by codprawn

I haven't got a leak - grrrr..... I think the pickup pipe has moved or kinked - is this possible?

Yes .. I had a tank once where the flexible pick up pipe used to float when the level dropped to about 1/3rd in the tank, and if you were in the rough stuff, bingo, no fuel, and engine cut out, just what you need in a force 6. I had to wire a heavy nut onto it to hold it down. Manufacturers shouldn't get away with poor design like that