So After trying everything to no avail I brought it to a mechanic who finally determined the new primer pump was causing the problem but they didnt know why.

On two different occasions they put the old one back on and it started right up. I still feel like there is power loss due to air entering the primer pump, But I see no other option that to try and make it work with the new one.

I went to a MB dealership here and they showed me a diagram of the primer assembly and a picture of the original pump and they said they would could order it and they did. I went to pick it up and it was the same BOSCH primer pump that Ive been trying (except with a price tag twice as high) Thankfully they let me return it.

Any Ideas? Can you get the old screw off primer pumps new anywhere? or are we stuck with the newer BOSCH ones.?