Plumbers Putty and PVC

Hi,

I think I may have done something bad. I used plumber's putty on the thread of a 3 inch PVC drainout cap on the advice of my father-in-law. Now the cap is firmly stuck and won't budge. I now see that the instructions on the putty say not to use on plastic. Have I ruined the cleanout? It is located in a place that would make it hard to replace and would likely require extensive replacement of PVC pipes and tees, something that is beyond my basic skills.

Can anyone suggest how I might get the cap off? Also, if the putty has only been on for about a month, will it have caused a lot of damage to the PVC?

Thanks

Cut the square end off, take a sawzall and cut to the 10 and 2 position but stop at the threads.

Take a chisel or screwdriver and bust that triangle out and cap will release at that point.

Use a solid brass cap and use a pliable thread sealant that doesn't harden over time.


If you can't do the above, call in a licensed plumber.

Hi,

Thanks for the advice. Should I use a brass cap even though the pipe itself is PVC? Also, will the threads on the cleanout pipe be OK after having had plumbers putty on them?

Thanks

I like brass because it will last. PVC becomes brittle at those caps and shatter when you put a pipe wrench to them with any hard strain.

A physical injury can follow with that abrupt motion when it happens as well. You're chatting with a fellow that's unscrewed thousands of them over the years looking for the pot of gold at the end of the rainbow.


The putty will easily peel out of the threads; use a wire bristled brush and clean it.

Plumber's putty has a petroleum base to it so if you left it in there for years, it would of definitely turned yellow over time.


Why are you having to gain access to your cleanouts so often? Problem drain?

Hi,

Thanks for the advice.

I had an issue with the septic earlier this year resulting in a backup into the basement so we tired to snake out the line. Turned out to be the septic requiring a whole new leach field (the old on had collapsed). However, the clean out cap leaked which is what lead me to use plumbers putty on the cap. Then I heard someone say that you should not use putty on PVC and that the pipes would be damaged by the putty. So now I am trying to do some damage control and trying to get all the putty out.

Do you think I should bother to remove all the putty and put on a new cap now, or just wait until I have a real problem that will require removing the cap?

Thanks

Plumbers Putty should never be on any threads. Pipe dope paste can be used, but on plastic needs to be white teflon base, not petroleum based.

You may get it to budge by applying heat form a hair dryer, nothing hotter. Warm evenly around the fitting and it might come off. If not it's time for the old sawzall surgeon.

plug

Use a bigger wrench. Putty, or rather the oil in it, can weld the plug in place but more force should loosen it. Use a plastic plug with Teflon tape or a plastic compatible joint compound. IF you use a brass plug, it may/will corrode from contact with the water and the corrosion WILL crack the female thread it is screwed into.

Thanks for the advice.

I think I will try and warm up the cap, then find the biggest wrench I can and give it a crack.

I was wondering if something like liquid wrench would help loosen the cap? Would it soften the putty without eating away at the PVC?

Also, how many times should I wrap teflon tape around the thread to ensure a good seal? The last time I used tape, the cap continued to leak and thats wehn my father-in-law told me to use putty. I also found some pipe joint compound (Oatey) that says its safe for PVC, if I used this, is the seal permanent or can the cap be easily removed in future?

Thanks

Update

Hi,

So based on the advice I received, I ran to the store and picked up a 24" pipe wrench which worked perfectly to remove the stuck cap. However, whilst I was cleaning out the putty with a wire brush, I noticed that the thread on the pipe had a worn spot which looks like it may have been caused by an electric snake as it is about the same diameter as a snake line. Probably caused by a previous owner of the home (we've only been here 1 year). The thread is worn almost complete down at that one spot. I can't replace the cleanout without major re-plumbing as it is glued to a tee which is attached to our basement toilet. I replaced the drain cap using some teflon tape and hopefully this will be enough to prevent leaks. If it does leak, can I use pipe compound (Oatey Great white) to seal the cap? I do not really want to replace the cleanout completely since we cannot afford a major plumbing expense at the moment.

Thanks