Injection pump bypass valve spring
 

I have measured too many of these this year at or near 1/2 the correct length = very low fuel pressure feeding the injection pump..

Please read the following threads and correct this simple but important issue on your injection pump before it causes problems..

Fuel pressure relief valve adjustment
http://www.peachparts.com/shopforum/diesel-discussion/234609-fuel-pressure-relief-valve-adjustment.html#post1983946

Fuel injection pump starvation with good a good lift pump
http://www.peachparts.com/shopforum/diesel-discussion/247039-fuel-injection-pump-starvation-good-lift-pump.html#post2133911



0000747284 Diesel fuel return valve/banjo bolt
http://www.peachparts.com/shopforum/mercedes-parts-reference-library/246848-0000747284-diesel-fuel-return-valve-banjo-bolt.html#post2131649

6010700146 Diesel fuel return valve/banjo bolt
http://www.peachparts.com/shopforum/mercedes-parts-reference-library/247163-6010700146-diesel-fuel-return-valve-banjo-bolt.html#post2135283

6010700646 Diesel fuel return valve/banjo bolt
http://www.peachparts.com/shopforum/mercedes-parts-reference-library/247464-6010700646-diesel-fuel-return-valve-banjo-bolt.html#post2139100