My 1984 300CD with 225K will start up, but sometimes stalls when I put it in drive or depress the accelerator pedal. Once it has stalled I can't get it going unless I use the diesel primer pump (older white plastic kind). Once I pump some fuel through the filters, it is good to go for a month or so as my daily driver. The car usually runs great and never smokes upon starting. Also, when i use the primer pump- fuel leaks out while I am pumping but does not leak once I screw it shut again. This problem started about a month after I changed both fuel filters.

Is air getting in the fuel system through the primer pump or is it a bigger problem?

Thanks for any advice.

__________________
1984 300CD 225K

I use the diesel primer pump (older white plastic kind)
this is a known failure point (famous for leaking and allowing air into the fuel system) get and install the newer style primer pump
also look into replacing the fuel lines to the primary(clear one) and the short one to the primer pump there's a good chance of air leaks there.
New fuel lines have less chance of developing cracks that you can't see



http://www.pelicanparts.com/catalog/SuperCat/3337/MBZ_3337_FULINJ_pg1.htm#item3

Thanks Partscarver. I appreciate your knowledge/advice. I will swap out the primer pump and the fuel lines you mentioned.

__________________
1984 300CD 225K