internal temperature of meat wont go above 130 to 140?

I have a new char-griller smoker with a side fire box and I have tried smoking a small pork tri-tip and a small Boston butt pork shoulder but I can't seem to get the internal temp of the meat above 130 to 140 no matter how long i leave it in the smoker. I'm using a combination of lump charcoal and wood chunks for fuel in the fire box with a drip pan filled with a couple inches of water in the smoking chamber beneath the meat. I smoked the 2 # tri-tip for six hours and the 4 # shoulder for twelve hours basting once an hour at 200 to 250 and the internal temp of the meat never got above 130 to 140? i got a new meat thermometer and tested it in the oven and its reading correctly and the smoker temperature gauge seems to be reading correctly. I don't want to serve the meat to my family if it hasn't reached temp for food safety reasons. Is the dry rub and basting of the meat creating a heat resistant crust? Do you have any ideas or suggestions? Please advise. Thanks!