1986 300sdl wont start please advise

[calimercedes]

my car does not want to start.. im here in california.. its not like we have very cold weather.. i was driving the car 3 days ago.. i parked it .. and this morning i tried starting , and it just cranks over but does not want to start. its not the battery, because the battery is brand new. but even that crancking so much , it drains the battery and i have to put a charger on it.. do you think i would have problems with my glow plugs? or glow plug relay? or do you think its a vaccum shut off valve problem which mightve stuck close.. i was thinking about fuel filters , but i dont think that will cause it not to start. the car is cream puff, with only 141.000 miles, and the earliest appointment my mechanic gave was next monday , so i thought i should post this up and maybe i can get some suggestions that will help me out before taking it to the big buck mechanic.. well any suggestions will help really... thank you .
john b.