Forum Discussion

RVcircus's avatar
RVcircus
Explorer II
Mar 22, 2016

How we repaired the threads in our RV water heater

When we purchased the trailer used, the threads were beat up pretty badly and it makes winterizing and de-winterizing a pain in the butt. I only need to deal with it a few times each year, but it's a problem a don't necessarily need to deal with. This past week I decided to finally chase the threads to clean them up.

The treads on the Suburban anode rod are standard 3/4" NPT. I would highly recommend using a thread chased to cleanup the threads, but I already had a tap on hand and used that. If you use a tap be VERY careful since it will cut new threads.

Below are the tools and supplied we used to complete the job:

- 1 1/16" socket with ratchet
- 3/4" NPT thread chaser
- Tap handle
- Cutting oil - I used cooking oil since I didn't want anything toxic in my water. I'm sure there's a better option, but I'm only chasing a few threads.
- Something to flush hot water tank
- Teflon tape for threads
- New anode rod

Checkout this video to see how we did it at https://youtu.be/572GWpWNodI

And our related blog post at http://www.rvcircus.com/cleaned-threads-suburban-water-hearer/
  • RVcircus's avatar
    RVcircus
    Explorer II
    Mar 26, 2016
    westend wrote:
    Tip: To ease the tool into the hole and break up some of the crud in the threads, I use acid, usually phosphoric. The cheapest source of phosphoric I've found is Water Softener Cleaner, green liquid in a bottle. Spray or brush it on the threads prior to mechanical thread chasing.


    Awesome tip! I've never heard of using acid to clenup the threads. This is why I love this forum!

    westend wrote:

    RV,
    You are getting a pretty extensive video library compiled. You may get to a point to be like Mark Polk. He gets all kinds of sponsorship and free RV components because of his viewership.
    Best of luck and keep the vids coming. Good stuff.


    Thanks for the encouraging words! I've been doing the videos for fun and to hopefully help, encourage, or at least amuse others along the way. At this point I set some goals for myself and they all revolve around producing better/more helpful content.

    I am little shocked that my wife hasn't slapped my hand yet when it comes to the ongoing costs of making the videos, but I guess she considers it a hobby. I like to drop hints for better equipment, but I don't know if she's ignoring me or buying into my madness;) I'm sure those sponsorship's help when it comes to making better videos, but I don't think hocking some products for a little $$ sounds too fun. I guess there's give and take there.
  • westend's avatar
    westend
    Explorer
    Mar 23, 2016
    Tip: To ease the tool into the hole and break up some of the crud in the threads, I use acid, usually phosphoric. The cheapest source of phosphoric I've found is Water Softener Cleaner, green liquid in a bottle. Spray or brush it on the threads prior to mechanical thread chasing.

    RV,
    You are getting a pretty extensive video library compiled. You may get to a point to be like Mark Polk. He gets all kinds of sponsorship and free RV components because of his viewership.
    Best of luck and keep the vids coming. Good stuff.
  • Lynnmor's avatar
    Lynnmor
    Explorer
    Mar 23, 2016
    RVcircus wrote:
    byronlj wrote:
    For cleaning up large pipe threads for which I don't have a tap, I use a steel nipple and cut 3 grooves evenly spaced and parallel with the pipe across the threads. I use a cut off wheel in my portable grinder and only cut thread deep. This gives it a cutting edge and a gap for material to collect. Works just like a tap.
    Dave


    Interesting, I'll need to give that a try sometime. I've used a nipple to cleanup threads that weren't too bad, but have never seen one turned into a makeshift tap.


    You did it right the first time. The soft metal of a pipe nipple will mold to the water heater threads and not produce a good thread. You can get a tap that is good enough on Ebay for $10 to $15. Someone not skilled with using a tap could easily damage the threaded hole, so explain that the tap must be run in as far as possible by hand before using any kind of tool.
  • RVcircus's avatar
    RVcircus
    Explorer II
    Mar 23, 2016
    byronlj wrote:
    For cleaning up large pipe threads for which I don't have a tap, I use a steel nipple and cut 3 grooves evenly spaced and parallel with the pipe across the threads. I use a cut off wheel in my portable grinder and only cut thread deep. This gives it a cutting edge and a gap for material to collect. Works just like a tap.
    Dave


    Interesting, I'll need to give that a try sometime. I've used a nipple to cleanup threads that weren't too bad, but have never neen one turned into a makeshift tap.
  • byronlj's avatar
    byronlj
    Explorer
    Mar 23, 2016
    For cleaning up large pipe threads for which I don't have a tap, I use a steel nipple and cut 3 grooves evenly spaced and parallel with the pipe across the threads. I use a cut off wheel in my portable grinder and only cut thread deep. This gives it a cutting edge and a gap for material to collect. Works just like a tap.
    Dave
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Mar 22, 2016
    3/4" NPT steel nipple 6" in length works as a thread chaser

    1/2" brass one works for Atwood also....aluminum threads

    Simply start the nipple in drain hole by hand then using pliers/channel locks work the nipple back/forth a little at a time until nipple is seated as NPT threads are 'tapered'

    Then remove and rinse/flush

About DIY Maintenance

RV projects you can tackle on your own with a few friendly pointers.4,353 PostsLatest Activity: Feb 14, 2025