Petcock Lube?

[Garry 2r's]

Getting ready put new diaphragm in my petcock and was wondering if anyone ever put some glycerin on the rubber to keep things pliable and seal better. We always used it on vending machine parts to help seal check valve's. I had a extra petcock that failed on me last year took it apart lightly added glycerin to parts re-assembled and it passed a vacuum test. Not sure if this would help longevity of our petcock's.

Thanks Garry

[us385south]

I think most posters are staying away from these post based on it title...