just 2 weeks ago I replaced the battery and the alternator. two weeks have gone by and it has had some trouble starting and it has been getting progressively harder and harder to start. I have been riding around for the last 2 weeks with no electrical on, except for head lights, and now it will barely start at all. and even after 20-30 mins of driving, which should charge the battery, it wont start with out a jump

. I dont have a volt meter, so I cannot give the voltage drops for when the glow plugs are running or when the car is cranking, but it cranks slowly and sometimes it will try and speed up. but once it gets cranked everything is fine, no strange noises or anything. This is getting to be bad.
now for the questions; is the starter bad? every "i dont know about diesel" fool i have come across says "sounds like your not getting fuel" but I dont believe them cause it still runs fine, if i can get it cranked, Does anyone thing it would be a fuel problem (both filters changed 4 weeks ago and still looking clean)?
Anny suggestions would be appreciated, thanks.