Bob, NO NO DON'T EVEN TRY TO USE A TORCH, REMEMBER YOUR DEALING WITH AN EXPLOSIVE, RE-- A TANK AND OIL, WHICH NOT ONLY CAN CATCH ON FIRE BUT THE FUMES CAN AND WILL EXPLODE WITH EVEN A SPARK.!!!!!!!!!!
Use a "cheater" or a larger pipe wrench. In the plumbing business a cheater is a length of pipe sled over the handle of a pipe wrench. 1/ place the pipe wrench jaws so that three points of the wrench are touching the pipe when you bit down on the pipe wrench.] 2/ now simply slide the pipe over the handle of the pipe wrench. 3/ Put your foot against the end of the pipe and push your weight against it. 4/ It should move. 5/ If not use a longer cheater pipe. Or ask some to assist you. 6/ Don't forget to make sure the jaws touch on 3 points of the pipe wrench to the pipe. good luck, brAin