ESP 1.9D no longer boosts after assembly!!

Hi, I installed a 1.9 diesel engine with 54 horsepower from a Renault Rapid into my boat, and my problem is that the fuel pump isn't working anymore. I had to disassemble it because the engine had been sitting for 3 years and the pump was completely clogged. I've taken the pump apart twice now and haven't found anything wrong. I urgently need help .

The pump is a Bosch VER588.

Did you also verschandeln the wing cell pump?

Sure, twice. "Is it possible that the problem is due to the overflow pipe being too large? "

Do you mean the return line?

And why are you opening two threads on the same topic?