I got a dt245 this fall. Thanks to a new 880 CCA battery and a magnetic block heater it has started pretty good this week at 0 or below temps. What I would like to know is about the decompression knob. The cable and knob are rusted and won't move at all. The other end of the cable ends near what I think is a decompression lever. Moving the lever has no noticeable effect on the cranking speed, if it is running there is still no difference. My question is what does it do and is the decompression feature activated with the lever up or to the left?