I have a 2000 Discovery with a chasis mounted 100 pound tank, It has liquid near the bottom of the tank near a brass plugm it is the odorizing liquid, why is it there???
Well OK John, but if he (OP) had not already opened the drain how would he have known the oil was there? Purging a tank is easy, instructions on the internet, and anyone can do it safely. A little air in a 25 gal MH tank is not going to make it go BOOM!