I suspect the bad stainless elbows were Chinese castings of dubious metallurgy.
I made up the exhaust elbow I have on my genset (which gets far more hours than the main engine) from stainless I happened to have on board. I don't know if it is 304 or 316. I had to remove it a few weeks ago to because it had a small leak that rusted a mounting bolt. I sandblasted it clean of carbon and fixed the bad spot in the welding. The fitting showed no signs of corrosion. I remounted it using stainless mounting bolts and so far it has remained clean and leak-free. I have had no experience with aluminum and hot saltwater. Fischer-Panda used to use seawater to cool the generator end of their gensets and now I believe they use freshwater cooling instead. On the other hand, I have an aluminum superstructure. The surfaces exposed to the weather are smooth and clean, where the inside surfaces tend to corrode. I do know that the USCG does not allow stainless gasoline tanks because of the danger of pinhole corrosion and leakage. Norm S/V Bandersnatch Lying Julington Creek 30 07.695N 081 38.484W > I am finally gong to replace the exhaust elbows on my Beta Marine 14 hp diesels. They are full of pin holes (and larger some dime sized) and I am getting tires of mixing up JB weld to patch them. Beta says they no longer sell the Stainless ones as they had "issues" with them, and now offer them in cast aluminum at $122. ea. Cast aluminum sounds dodgie to me, what with dissimilar metals and such. Any one had any experience with exhaust elbows of this material? > Philip > > Philip & Marilyn Lange _______________________________________________ Liveaboard mailing list Liveaboard@liveaboardnow.org To adjust your membership settings over the web http://www.liveaboardnow.org/mailman/listinfo/liveaboard To subscribe send an email to liveaboard-j...@liveaboardnow.org To unsubscribe send an email to liveaboard-le...@liveaboardnow.org The archives are at http://www.liveaboardnow.org/pipermail/liveaboard/ To search the archives http://www.mail-archive.com/liveaboard@liveaboardnow.org The Mailman Users Guide can be found here http://www.gnu.org/software/mailman/mailman-member/index.html
