im not too sure on the drain, try to unhook the power wire to the alternator. but as far as the no start issue. pull the glow plugs out and clean the tips and test them for heat....... the super easy cheep way it to just use some wire right off the battery to see if they heat....lol watch out they get hot fast!!!! how long are you holding your button manually?? i would only hold it for about 10 sec at a time.