Mixing metals on fuel systems?

[JDCAVE]

Do the usual rules against mixing metals on boats still apply to fuel delivery fittings? I have aluminum tanks with SS fittings, but I used a brass compression fitting on the prototype fuel sight gauge. Is there a problem with that? They didn’t have SS compression fitting available but can get them in.

Jim

 

[C lectric]

A SS fitting would be best when attached to aluminum.
However, unless the fittings are exposed to water I doubt there will be a problem.
A bit further if the compression fitting is first attached to a SS fitting, ball valve or nipple between the aluminum tank and the compression fitting, then that is enough separation.

 

[Lepke]

Stay away from galvanized pipe and fittings. Diesel dissolves the zinc coating and it can end up in your injector pump or injectors. Black steel pipe is ok, but will rust if water is present in the fuel.

 

[Ski in NC]

Brass, bronze, steel, SS all ok in fuel system. Only need to be picky if area gets wet or damp. If in an ER, ok to mix them. I go brass on all unless I need something that can't be found in brass.

 

[JDCAVE]

Thanks everyone. All fittings and valves are SS all the way except for the brass compression fitting from SS valve to Teflon tubing. I’m a bit gun shy on all of this since the surveyor was so pissy on the sight gauge to begin with. At least this time it’s an easier fix if I need to change out the compression fittings.