Rotten Bronze

[Attikos]

I guess plumbing is a good enough place to put this:

The other day, I was cleaning the bilge. There's a bronze foot in it attached to a suction hose that in turn is attached to the backup manual bilge pump.

I lifted up that foot, turned it over, and began to wipe off the perforated bronze plate that was its strainer. The ^%$# plate collapsed. Broke into half a dozen pieces just from a light touch. The bronze, after 19 years in the bilge, was rotten and brittle.

All right, I can deal with this. I can just fold a piece of stainless steel screen wire, double I suppose, into the right size and slip it into the groove that held the plate.

Any reason not to do that? Electrolysis between bronze and stainless steel, for instance? Anyone else ever had bronze go rotten on him?

[Orion Jim]

Betting it wasn't bronze at all. Perhaps a brass strum box?

[Cheechako]

Doubt it was bronze to start with.

[Attikos]

You all have got me there. The pieces of the strainer are here on my desk in a plastic bag, but whether they're bronze, brass or pot metal I have no way of knowing.

[Reefmagnet]

Well, (in a Lionel Hutz voice), there's bronze and then there's bronze.

Lots of stuff on a boat seems to mix stainless steel with bronze. My rudder shaft is stainless steel and is attached directly to a bronze shoe and bronze shaft housing and shows no signs of corrosion in 30+ years.

A galvanic chart like below is an interesting way to compare the compatibility of metals and their likely resistance to electrolysis.

[Attikos]

I take it that means I can find some stainless steel screen somewhere and make a new strainer from it without staying awake worrying if it's going to fail this week.

Thanks, good to know.

[belizesailor]

I used fiberglass screen once, worked fine for many years.

[markpierce]

Don't trust bronze if it is put under stress. Once had the tiller break from the rudder post due to the failure of the bronze connection. Fitting replaced with quarter-inch stainless steel.

[HopCar]

Perko and other marine hardware manufactures make cast bronze strainers. The casting is bronze but it looks to me that they use peferated yellow brass for the screen it self.

You got 19 years out of yours. If yours is a Perko, you can buy a replacement screen for a few bucks. Not too bad.
PERKO Inc.

[Attikos]

That fiberglass screen idea is an attractive one. I could fasten it onto the foot with something, maybe just tie it on.

HopCar, I'm not aboard at present, so I don't know if it's a Perko foot. If this strainer plate is brass, though, it would explain why it grew brittle with years in the bilge water. I wouldn't think real bronze would have.

[belizesailor]

Originally Posted by Attikos

That fiberglass screen idea is an attractive one. I could fasten it onto the foot with something, maybe just tie it on.

HopCar, I'm not aboard at present, so I don't know if it's a Perko foot. If this strainer plate is brass, though, it would explain why it grew brittle with years in the bilge water. I wouldn't think real bronze would have.

Cable tie.

[NoTies]

Did it have a pinkish colouring?

[Attikos]

No, it's just brown.