I've got my new propane tank bolted to the under side...
And I have cut and bent and flared tubing ends...
ready to connect the tubing and tighten the flare nuts...

but a question...

I noticed that when I took the flare nuts apart there was a dark colored
greasy like substance on the threads... and maybe on the flared ends of the
tubing... Originally I though that might be old propane decomposed into
sludge... but now I'm wondering if the previous installer put a dab of axel
grease on the flares.... perhaps it assures a better seal???
Anybody know what that black stuff is on the flare ends?

thanks,

Bill Davidson