Bolting Aluminum

[scot]

I need to use some aluminum in the boat, what's best... bronze bolts or stainless bolts? I know the stainless eats the aluminum but I don't recall if the bronze fasteners do the same?

Main concern is the hose fittings into the aluminum tanks. I used Brass on my last boat and don't recall problems.. but I hope to never see these tanks again after the deck in installed.

Thanks

[Harry Babb]

Scot

Do not use the Bronze at all for fastening aluminum.

Of the 2 Stainless is the better choice

hb

[scot]

Thanks Harry,

I seemed to remember that bronze & aluminum were a no-no. Are the fuel tank pickups available in SS? I have only seen the brass ones in the marine catalogs. Supply & vent hose fitting are easy enough to find in SS.

[alano]

If you're talking about hose fittings into aluminum tank fittings, I used some experimental-built aircraft site to order anodized aluminum hose fittings for my pickups. Think it was aircraftspruce.com or something like that. Don't know if it's NMEA correct or not but figured there would be no dissimilar metal issue, hasn't in 7 years. Regards, Alan.

[matt ciarpella]

You may want to coat fasteners and contact point in Dielectric grease. It will help corrosion between dissimilar metals and will last a good while.

[White Bear]

The last time I installed new a pick-up in an aluminum tank, I made up an aluminum cover plate of sufficient thickness to allow the pick-up something to thread into, made a gasket to go between the cover plate and the tank, used stainless machine screws fitted into threaded holes in the tank top and coated with Tef-Gel to cut down on corrosion caused by the dissimilar metals. Years later, still working just fine.


By the way, the new pick-up was made necessary by an engine that kept stalling out once the fuel level dropped below a certain level on one tank, but would run perfectly on a full tank or on the other tank in the boat. As you can guess, the problem was caused by a crack in the pick-up tube that would allow the entry of air to the system once the fuel level dropped below the site of the crack.