Oily LP

I replaced my propane regulator because the pilot for the water heater kept going out. When I disconnected the regulator an oily liquid poured out of it. Can you tell me what that liquid is, and where did it come from?
Tom, (Redwood City, RI)

Tom, that oily molasses-type gunk is a residue from a combination of effects happening within the LP container. Chances are your LP container had been almost drained completely at some point as well as overfilled at another point; and probably repeatedly overfilled. Moisture in the container and the remnants of the odorant used to enable LP to be “smelled” sometimes coagulate into that sticky mess when liquid LP is allowed to enter the regulator. This situation will quickly ruin the regulator. 

Remember LP is stored as a liquid, but utilized as a vapor. During an overfilled condition, liquid will be forced-fed into the regulator. If liquid is forced through the regulator and into the black iron pipe manifold it could eventually find its way to the appliances and cause real havoc. Have a qualified technician disassemble the output hose from the regulator back to where it meets the black iron manifold and inspect for that oily goo. If some is found, keep disassembling the piping until no residue is located. All affected pipes, tubing and/or hoses will have to be replaced. There is no effective way to clean out that mess. Hopefully your appliances are still functioning okay. Remember, never have the LP container topped off; never fill more than 80%. Most containers are now equipped with an OPD (overfill protection device), so, thankfully, this situation is not as pervasive as it was in the past.