I have a 2007 Terry travel trailer. Recently we started having
problems lighting the stove, and the furnace failed to light as well.
In checking out the system, I found that there was no fuel shortage. I
then started trying to find out why there was a problem.

My rig is set up for extended stays with an extended stay coupling
that i have connected an external propane tank.

I usually leave one of the trailer tanks turned off and full, and have
the extend-a-stay module connected to that tank. I leave the other
tank turned on as a backup for when the external tank runs out of
fuel.

I first disconnected the extend-a-stay coupler from the system. I
found a large amount of waxy yellow grease coming out of the OPD
connector on the coupler. Due to the pressure of the gas, this residue
was frothy. I then disconnected the trailer supply line that is down
stream from the regulator. The same yellow oil/grease was dripping out
of the low pressure side of the regulator. I blew out the regulator as
much as I could, but could see that there was still a mess in the
regulator. I reconnected the house line to the regulator, and so far,
have had no further trouble.

My questions are:

What is this stuff?
Does it pose a danger to using the trailer?
How can I clean this out of the system?

Thanks for your help

Jeff