Thanks to the help of the fine experienced RV'ers here, I a about done. But as helpful as you advice has been, it has been an extremely frustrating experience, mainly due to just finding all the little tools/parts I needed, and I'm still not quite done!
Originally Posted by f1100turbo
Yes the anode rod nut is 3/4 pipe thread.
Do not run the tap all the way in tho.
Pipe threads are tapered so just run it in enough to clean threads
Originally Posted by joenic53
You have heard from some of the best, I wish you well.
Originally Posted by B47
And if I am not mistaken (I'm not a plumber) the tap you need in this case is the coarse threaded one, not the fine threaded one -correct?
Good question! If I had to go that route, and I just bought a "3/4 tap", will that have the correct thread? Is there a course and fine thread available? And if so, do I need the coarse?
Originally Posted by KyDan
I don't find a single 3/4 NPT tap at Harbor Freight online. They have sets
that include the large one but that costs as much as a single name
brand from others. I have no fear of using a HF tap in this case as they
are not cutting new threads in a blank hole, just trying to tease some
of the rust out of the existing threads.
A urge the use of a rotary wire brush in a drill motor first. Then you can
soak the threads with some liquid wrench rust disolver which is available
in small cans from hardware stores. Problem is that stuff is stinky.
Thorough flushing of the tank after this process is mandatory.
This is exactly what I did, have not got to the "3/4 tap" part yet and prob won't. First, I searched the entire town for a 1 1/16 socket. HF had a 1 1/4 and 27 mm, but no 1 1/16 without buying an entire set of impact sockets. Went 10 miles over to Home Depot as it showed online for a good price, and did not say it was online only as some things do. But nope! Then 2 different people at HD tell me: "I bet you can find it at Tupelo Hardware". This is an ancient old
building in downtown Tupelo, MS far from any of the malls, where Elvis Presley bought his 1st guitar- really, no joke! I had not been there for years. I go in and I see several very gray heads working there, and graying customers, all grayer even than me, I saw no one under 50. The grayest gent in the place goes on a hunt, gets down on his knees to reach back in a bin and says: "got two, how many do you want".
In the meantime, I had not been able to find a wire brush for a drill that would fit into the opening. ( Isn't this ridiculous? ) So I bought the smallest detail brush in stock at HF, and it won't quite fit into the hole!
But i manage to get it shoved in there anyway and twist it around, completely distorting most of the wires on the brush permanently, but I do end up seeing a little shiny metal and a hint of threads. In the meantime, the gent at Tupelo Hardware sells me a carbon steel Dremel brush. Hope it's ok to drill/brush these threads with carbon steel, cause I did!
I got some Evap-Rust from HF, which claims to be non-toxic for skin contact or even if ingested. Left a soaked paper towel sitting in the opening overnight. Dried out this morning and took the Dremel to it again. Now I am seeing plenty of threads.
You can get a pretty good flush with a cut off garden hose. By that I
mean a garden hose with no end on it. A hose with a threaded end won't
fit inside the anode hole but a hose with the end cut off will fit!
I often use a washing machine
hose cut in half. These are cheap and work great for filling your fresh
water tank as well as filling buckets and sprinkling cans around the campsite
or home gardens. I have one of these cut off hoses in my RV at all
I have been unable to find one of the hot water tank flush tools at two different RV sites, or anywhere else, locally! I can order one, and might for later. Or I might cut off a hose.
I put a wad of paper in the back of my anode socket so I can gently
push the anode against the threads. This helps hold the anode straight
while I turn the socket/extension with my hand. Once I've got 2 turns
I know it's started straight and then I use a large ratchet to finish the
As ugly as those threads look in the photo I think they can be salvaged
with the methods listed here. As I said earlier the tap is a last resort.
That's what I did. Got it started with the socket/extension by hand,, then used the ratchet. I can only go about 1 1/2 to 2 turns. ( seems to me it never in the past went in as far as I thought it should but I can't remember if it went in further than this ) I'd say about 75% of the threads are visible outside the pipe. But with the plumbers tape, I filled it up and left it under the pressure from the down-regulator, and there were no leaks after an hour or so. Then I re-filled and drained several times, and just let it drain while the hose pressure was still at max. Very clear water was coming out, but with some particles in the water, some of them rusty colored. After repeating the flush several times, there were almost no particles, and never was any rust color, just nice and clear. I guess I can assume there were no insects living in the tank, as I saw nothing but those fine particles being blown out of the tank. And not even those after a bunch of draining.
So looks like I am back in business. I'm probably going to order one of those flushing wands on line, or at least cut off a hose, and later do the job right. But I guess the question is: if it don't leak, is it in far enough? If it ain't broke, don't fix it? Or do I need to get one of those taps and see if I can extend it?