The problem I am dealing concerns the cracking speed of the motor. This is a 6L Ford diesel and it needs to developed sufficient pressure before it lets the engine start. THe faster the crank speed the faster the start. Even using the battery interconnect button does not help much. Of course, it can be fixed but as a work around it seems that having a fully charged battery does make a difference. There could well be a problem with some sort of unknown current draw - the battery was at 11.7V after 10 days or so. This 2007 unit is new to me. Also I should add that 120ac is not available where it is stored. It has 340 watts of solar.