If I remember right that should be a 603 engine. If its any thing like the 603 in my 300SDL there is no primer pump. It took forever for me to get fuel into the engine when I changed the fuel filters. I always get confused when it comes to the naming of the fuel filters. When I replaced my filters I added fuel to the big filter (I think it is properly called the secondary but???) by taking the bolt off the top and put a funnel in the hole. Then I added some diesel fuel; it made it much easier to start.

Are you sure that it is running diesel??? For some reason my gut is saying that it should start easier; I would double check that gas didnt accidently get put into it.

Good Luck,
Matt

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KI6CCA

Current Stable:
1987 300SDL
1980 450SEL

Out to Pasture:
1982 300D KIA (Rice Rocket vs. 123: He hit me at 80-100MPH I walked away he went to the hospital. Sounds fair to me!)
1985 300D EURO Scrapped (got more money from state than car was worth)
1979 & 1980 300SD Great Cars!