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Cleaning 1-1/2" tub drain line

Dave_23 Member Posts: 190
I have a section of 1-1/2" drain line running from a tub to 4" cast iron drain stack. The 1-1/2" line can't be removed or replaced. However, I do have access to clean it, if I could figure out how. It is reduced in diameter by about 50% by soap scum, accumulation, etc.

Is there a tool that would allow me to reach into the 1-1/2" line and pull out/scrape the interior accumulation? If so, any makes and models would be appreciated. My sense is that such a device would attach to the end of a fiber glass or steel rod.



  • RobG
    RobG Member Posts: 1,850

    The only way to clear a tub drain is through the overflow with an electric snake. Sometimes, depending on the type of tub drain, the blockage may be right at the tee of the overflow and drain. You may be able to rent a snake with 1/4" cable from a tool rental company. I still use my Ridgid K-50 for cleaning most drains. I've had it for about 30 years and I bought it used! You have to be careful not to have to much cable out of the drum to prevent kinking the cable. The hardest part is getting through the trap. It might be worth it to call a pro.

  • jonny88
    jonny88 Member Posts: 1,139
    that trap

    that trap can be a nightmare.Especially when you go into older buildings with galv waste.There is no such thing as the pipe cant be removed from stack and be replaced.You get a good plumber in there and you will see,a lot of guys like to be told it cant be done and take great pleasure in doing it.Be careful
  • icesailor
    icesailor Member Posts: 7,265
    Line Composition:

    If the drain line is old and made out of galvanized steel, it needs to be replaced because even if you get a "snake" through the trap, it is probably reduced in size by more than just soap scum. If it is copper or PVC, you can clean out the soap scum with high powered drain cleaner (Drain-O isn't high powered). If the drain isn't one with a lever piece in the Tub Shoe that operated the pop-up, and can be completely removed, you can use a 1 1/2"/1 1/4" blow up test plug in one side of the shoe and use a drain king type water expansion plug  in the other end. Adapted and connected to a portable air compressor. The swirling air will loosen it up. Once loosened up, you can switch to water.

    I've used a pot of almost boiling water with dishwasher detergent (Cascade) mixed with the water. It sometimes helps. SOME wholesalers sell dangerous drain cleaners that can be a real problem if they don't work. They can quickly destroy the finish of a porcelain tub. Not all wholesalers want to carry and sell serious drain cleaners because of liability. Some "safe" drain cleaners are no more exciting than kissing your mother in law or grandmother. Drain cleaning is sort of an acquired skill from trial and error and experience. Like priming shallow well water pumps. No one way works best. Other than adding water as needed. If the drain pipe is galvanized steel pipe and is accessible, cut it off two inches before it goes into the stack (or wherever) and connect it with No-Hub Couplings and PVC. You can use Fernco Couplings if you aren't in it for the long haul. They rot out in time. No Hub type couplings have the stainless steel shell around the gasket and don't rot out.

    Not for the faint of heart.
  • jumper
    jumper Member Posts: 1,593
    how old?

    Old ferrous sharp bend traps rust closed. No tool I've seen will open the up leg from the down leg.

    This is something I wonder about.Why do bath and shower traps often have such sharp turn?
  • icesailor
    icesailor Member Posts: 7,265
    Trap Size:

    That was because of some old hateful dead engineer that didn't want people running snakes through their traps. And back then, all they usually used were flat tape snakes. Try getting one of those through a trap.
  • Dave_23
    Dave_23 Member Posts: 190
    edited August 2014

    For starters, I had to build my own trap out of Sch 40 to replace the old drum trap. Reason being is that the old drum trap spanned a doubled joist. I was able to install a cleanout using a T and cleanout screwcap on the downstream side of the trap. I connected the galvanized to the PVC using a no-hub. After installing the trap/cleanout assembly, I was able snake the galvanized section. Much hair came out, however I'm not sure I did much about the accumulation around the ID of the galvanized. Even so, snaking the line with a Brasscraft drum auger helped considerably, however, it doesn't have much of a bit.
  • icesailor
    icesailor Member Posts: 7,265
    Drum Traps:

    Did I miss where you said it was a drum trap?

    Drum Traps are illegal. Right nasty they are,
  • Dave_23
    Dave_23 Member Posts: 190
    edited August 2014
    Drum traps

    My house is from the 1920's. They may have been legal then. It weighed a ton when I cut it out with my sawzall.
  • icesailor
    icesailor Member Posts: 7,265
    Drum Traps:

    They would be legal if they were self scouring.

    They are NOT legal when the cap is on the top. The cap MUST be in the water seal.

    I've never seen one installed with the cap on the bottom.
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