I purchases a B6000 this past week, the seller said it starts hard but runs fine. He said he tried to start it before I arrived and run the battery dead. I bought it anyway, got it home charged the battery, changed the filters and fuel, changed the oil and cleaned the filter. I bled the lines and getting fuel to the end of the lines but it will not start. dark grey smoke comes out the exhaust and almost fired once but will not. I glow plug the heck out of it but still nothing. Can someone please help? Is there a way to check the compression and what should it be? Thanks in advance for a solution.