My 750 taylor is running black liquid creosite out the back access door. I expected some but a half coffee can worth in 3-days can't be normal.The tubes inside are getting coated with a black sticky tar. My taylor dealer suggested to raise the back of the stove up 1-in. to let the stuff go more toward the fire box to be burnt up. Do you folks think is correct or do I have a chimney issue. I have the original stack height when it was new. Thanks,this is my first owb & my first post on this site.