Bronze Stem Head Fitting Inspection

[Storm]

Could you tell me how to inspect a bronze stem head fitting? I am in the process of replacing all my stainless steel chain plates. How do you inspect bronze fittings for condition. Do I just look for cracks? Or do bronze fittings also have a life span based on age?
Thanks

[benz]

The nice thing about bronze is that what you see is what you get. If there is pitting with light pinkish coloration inside, then you've suffered from electrolysis. If you grind that out and find bright yellow metal underneath, you're ok. If there's no electrolysis, and there's no obvious cracks or stress marks from metal fatigue (highly unlikely in that sort of piece,) it will be OK.
Best
Ben

[Brion Toss]

Hi,
First, are you certain that it is bronze? Many allegedly bronze fittings are actually brass, including those made of "naval bronze" and "manganese bronze."
Second, while bronze is much more fatigue-resistant than stainless, it will harden in time. If this is an old fitting, used regularly, it might need to be annealed.
Third, bronze is less noble than stainless, so a prime place to check for galvanic action is under fasteners.
Fair leads,
Brion Toss

[Douglas]

Someone once told me that a useable bronze fitting will be one that has a clear ring when tapped with a hammer and suspended with a wire ,,,,, thus a cracked bronze fitting will sound a "thud" instead of a ring .