MEP003a cylinder 3 and 4 fuel issue

[johnny5o]

I recently rebuilt the injector pump, installed adapter block for 3 to 2 filters, and fully cleaned all the lines and tank on my MEP003a. I now have to crack the fuel sending lines on both #3 and 4 cylinders to get them to fire. 1 and 2 prime and fire fine automatically. I checked all connections and they are all tight. Once fuel starts coming out of the lines I seal them and the unit runs beautifully but it will not start if I don't do this. It will restart if it has only been a few minutes but after an hour or two those cylinders lose prime again. Any recommendations on what I am looking for?

 

[Bmxenbrett]

Im not very knowledgeable about that specific pump but it does sound like you have a check valve not properly closing.

Can you swap the injectors to see if the problem moves?