Aluminum Fuel Tank Problem

[Benny]

Ahoy All:

I have a tank problem on my boat. I have smelled diesel in the bilge and have drained the tank. Cut 2 large inspection ports in the top and found only a little sludge in the bottom corner but when I cleaned it up, there was some minor pitting all over that bottom panel which must be how the fuel got out. There must be a few pin holes. There was also a dark oily film covering the sides of the tank as well which wipes off. I assume this is diesel bacterial residue?.

I am going to thoroughly clean the tank inside however, what is the best way to deal with the pitting and leaks. I thought of roughing it up and then using epoxy and cover the whole bottom panel which is about 6 inches wide by 4 feet long.

Has anyone done this job successfully and if so, what did you use. Also what sealant did you use to seal around the inspection ports that diesel does not affect?

Thanks for the help, Randy

[DeepFrz]

Good old boat has some online articles including the following one:

The epoxy cure -- Norman Ralph repaired his aluminum fuel tank leaks by installing an inspection port and using epoxy filler to patch the thin areas. Repairing a diesel tank without removing it from the boat

http://goodoldboat.com:8080/GOBWeb/G...d=Start+Search

There were some other fuel tank articles as well including testing for leaks.

[Benny]

Thanks DeepFrz - the article confirms that epoxy is the way to go for a repair without removing the tank. BTW - I an going to install a second Racor filter and have a bypass dual system so I can switch the fuel flow from one filter to the other to change it and keep the engine running. This is to prevent the clogging of the primary filter if alot of sludge gets sucked up into the system - which of course would happen at exactly the wrong moment. If anyone wants a diagram, let me know.

Best regards, Randy

[delmarrey]

Your not using biodiesel are you? That stuff is rough on epoxy.

As for the water, there are additives to help prevent moisture build up, also keeping the tank full when not in use. Or completely empty for a winter storage. Now that you have inspection covers you can clean it out every spring start up.

[Benny]

Delmarrey - don't know if my marina uses biodiesel but with enviro issues it's a bet it will to that way in the future - so maybe there is another compound available to do the fix - any thoughts out there?

Thanks, Randy

[DeepFrz]

Randy,
You said you had the fuel tank out of the boat so why not take it to a metal shop and have it repaired?

First test it under pressure with some soapy water to see where the leaks are. You may decide to have a new tank fabricated if the leaks are all over the tank.

[delmarrey]

Go to this thread and in post #2 there is a link that gives more detail about the use of epoxy. Also the whole thread might be of interest in relation to tanks.

http://www.cruisersforum.com/forums/...ighlight=tanks

[Benny]

DeepFrz - the tank is glassed in and I would have to cut out the strbrd settee and half the cabin sole to get it out - 80 gallon tank you see - I don't want to do this unless absolutely necessary to replace it so I'm going ahead with the epoxy which I'll give a good thick coat thickened with aluminum powder on the suspect areas on the bottom panel I mentioned and then epoxy 'paint' all the rest of the tank to minimize any future problems. I will etch the whole tank first.

I have purchased a good face mask with appropriate gas/fume/vapour filters to work on the tank to ensure safety as I will need to get my head down inside some of the time.

Thanks to you and Delmarrey for the info and relevant threads.

[DeepFrz]

Welcome.
Sorry, I thought you had said that you had removed the tank but realize now it was a senior moment. Good luck and keep us posted.