Splicing 4" PVC fitting into existing line

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Splicing 4" PVC fitting into existing line

Author: Cminter (TX)

After reading advice from other posts have decided to use banded couplings (hopefully shielded if I can get them) rather than PVC repair couplings to splice a 90deg. sweep into the 4" line that drains to my septic. My question is whether it is advisable to put a thin coating of motor/ bar and chain oil on the inside surface of the coupling to improve the seal, or if this is unnecessary or just a bad idea because it might cause the rubber to deteriorate. The line has been buried in a sandy loam so is not in pristine condition. Thanks.

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Re: Splicing 4" PVC fitting into existing line
Author: hj (AZ) It MIGHT damage the coupling, but it probably WOULD damage the pipe.
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Re: Splicing 4" PVC fitting into existing line
Author: packy (MA) if you are worried about a good seal, put a little pipe dope on the pipe. use the type that is safe for PVC.
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Re: Splicing 4" PVC fitting into existing line
Author: North Carolina Plumber (NC) There is no need for to apply any sealant. The mission couplings are very good at sealing. I routinely air test them at 5 PSI with no problems at all.
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Re: Splicing 4" PVC fitting into existing line
Author: packy (MA) i don't use anything on them either. but if the DIYer is happier using some then go for it..it won't do any harm..
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