Treated wood and aluminum??

[Fighterpilot]

I'm installing a fuel filtering sysem on the new aluminum tanks I just installed. I'm using a 1 by 8 inch treated board 23 inches long fastened to a flange on the fuel tank to hold the fuel fliter heads. Will the treated lumber be detrimental to the aluminum? If so, significant enough to degrade flange within the next 20 years? Thanks

 

[HopCar]

I think I'd put a piece of plastic between the wood and aluminum just to be on the safe side. I don't know how the treated wood would affect the aluminum but it's easy to prevent possible problems. Don't some wood preservitives have copper in them?

 

[Art]

How to Install an Aluminum Fuel Tank, by David Pascoe
http://www.yachtsurvey.com/fueltank.htm

 

[Phil Fill]

I would be more concerned about the kind of fasteners and fitting used to install than treated wood. Aluminum has a very low galvanic rating compared to mild steel, SS, copper/bronze.

 

[Fighterpilot]

I cut a strip of plastic out of a 1 gal oil jug and placed that between the treated board and the alum. mounting flange.

As for mounting the tank, ss bolts down thru flanges welded to the side of the tank on the sides I could get to. Front, aft, and inboard. Some day the tank will have to come out to do maintenance on the muffler and exhaust stack that runs down the outboard side of the tank and the hull. Couldn't see myself trying to get it out after using 5200 like Pascoe suggests. Besides if it last another 20 years it isn't going to be my problem anyway. Thanks for the suggestion on the plastic.

 

[skipperdude]

The only issue you may have is the SS bolts going throught he aluminum. Two dissimilar metals. You will get some corrosion at the bolts. If it is flanged you could make the holes a bit bigger than the bolts and perhaps sleeve the bolts with a grommit. Plastic or even a bit of rubber tubing or something to prevent the contact between the two metals. Then again it will be years before you see any real issues with corrosion.
SD