No start, odd noise cranking.

lmorris · February 10, 2022

Other diesel tech has an E350 no start. Fuel pressure is low, around 35 psi cranking. ICP is slow to build and does reach 1500 psi. Once it reaches 1500 psi the engine starts making a loud clacking noise that seems to follow the injector firing order. The turbo is dusted and he is getting ready to do a manual compression test. Anyone have any ideas on what may be causing the loud clacking noise. It is not the same as a low fuel pressure cackle. It sounds too mechanical. And not slow enough to be valve train.

Update. He pulled the upper filter and found what looks like salt. Possibly Def, and a lot of rust. He had one valve cover off and decided to pull 2 injectors. Both are black in the fuel section. Problem found. Internally, the injectors must be hammering. Manual compression on one cylinder, 250 psi, and that's not the one that relative compression flagged as 7% low.