Robert Green wrote:


Rare, but not unheard of:

Turning the main valve on rather quickly puts a pressure surge in
the pipes. If a joint or section of pipe was fragile, this sudden
surge could cause a failure.

Just jostling a section of fragile pipe can cause leaking. This
confirms my decision to search high and low for a new cartridge for
my kitchen sink instead of replacing the whole assembly. Old
plumbing is vengeful. Bother it enough and it will fight back. Hard.

Let us gather at the riv-er, the beautiful, the beautiful riv-er. Amen,
brother.


I learned that putting a new toilet in. Everything up the line from
what I was working on failed because the joints were old, calcified
and ready to go. And they went. A simple toilet replacement ended
up with torn up walls, multiple trips to the plumbing supply house
and visits to the neighbors to use their toilets. I did learn that
if you're going to be applying any serious force to an old pipe to
strap it down as well as you can to eliminate the chance of it acting
as a huge lever and damaging a joint upstream.

Same damn thing happened when the shower diverter valve failed.
After 70 years stuff happens.

Sometimes it's not the pipe's fault.

A bit back I posted an expose regarding my attempt to replace a standard
hose bib with a quarter-turn valve.

Short version:
I put the wrench on the existing bib and gave it a little nudge. The pipe
holding the bib disintegrated! The pipe exited the brick veneer through a
junction between two bricks and was mortared into place. The mortar had
eaten (virtually) through the galvanized pipe.

This turned a straight-forward afternoon task in to a several hundred
curseword job as a 2x2' section of brick wall had to be removed to get to
the pipe on the other side. But wait, it gets better!

I had FOUR of these goddamn pipes to mess with, each with varying degrees of
corruption.

Still, I was lucky to have discovered the issue before a catastrophic
failure.