Does pipe dope dry out with age and then allow leaks?


I have iron pipe ove 60 years old. The dope looks like hard glue. Rusted too. I was thinking pipe that old wouldnt be prone to leak.... in fact not sure it could even be unthreaded!

It does happen with gas lines, but have never seen it on water pipes.

I was hunting a gas leak... soaped a bunch of old joints with hardened dope... is getting them wet bad?

It looks like hard epoxy on it, certainly not something that can be smeared or wiped off.

What did they use 60 years ago?



Edited 1 times.

when I started (early 60's) we used a grey pipe dope that did not have Teflon bits in it. PTFE was just coming onto the market at that time. old timers used wicking and plain old pipe dope on water pipes but just plain dope on gas as wicking was not allowed on gas pipes.
the pipe dope was oil based with some kind of clay mixed in to give it body.
unlike hj, I have not seen it leak after decades of drying out.

around here you must do a complete retest of gas lines if the service is off for a year...see 60+ year old piping hold a retest just fine and 10 year old systems fail.Also find nipples installed hand tight all the time....no leaks for many years.