In article ,
Winston wrote:

Salmon Egg wrote:

(...)

It is experiences like these that make me wary of inspecting and
replacing the anode. I am pretty sure I will get another few years out
of the heater. In the back of my mind is the thought of the effort of
taking out the anode only to find out everything was ok until I screwed
things up.

Nonsense.

Measure the flats of the existing anode and pick up a
matching socket for your breaker bar.

Using a Q-tip, daub under the head of the anode with Kroil.
http://www.kanolabs.com/

Do not spray directly on to your water heater!

Keep the Kroil away from hot parts, like the exhaust stack!
Use with adequate ventilation and keep Kroil away from open
flame.

Repeat the application every day for a week.

Shut off the water to the house; turn off the gas to the heater.
Open a hose bib in the front yard to relieve pressure
in the lines.

Use a couple damp rags to clean the dust and Kroil off
the anode cap and surrounding area.

Snap your socket on to your breaker bar and spin the
old anode out of the tank. It will still be hot!

Inspect the anode. Replace if unduly worn.
Decalcify if necessary.

Apply a THIN coating of graphite to the anode threads
using a pencil.

Spin the new anode back into the tank and tighten.

Shut off the hose bib in the front yard.

Turn on the water and check for leaks.

No leaks? Turn the gas back on and light the pilot.

Bob's your uncle.

--Winston

Holy Crap. I wouldn't go to all that trouble if pussy was involved. When
the anode is shot, the water heater can't have much life left in it
anyway. I say, don't drain the heater, and leave the anode alone. Life's
too short to worry about milking an extra year or two out of a lowly
water heater.