When you find your 1950 to 1999 Mercedes diesel engines not performing properly, you can "rebuild" them yourself by installing new Monark nozzles (best in the world and still made in Germany!). In many cases that will solve your problems. BUT keep in mind.... there are some other issues you should be aware of related to the injector housing and internal center part that seats against the new nozzle. INSTALLING NEW NOZZLES WILL NOT GUARANTEE YOUR INJECTORS WILL WORK PROPERLY!
Problem & Solution
Common among these chassis:
Kent explains the other issues, starting with the extreme importance of not allowing the slightest bit of dirt to get into the injector housing or nozzle. Then he talks about a couple issues with the internal parts and the upper part of the housing. These injectors are getting older and older and sometimes you many have to replace the housings and / or the center piece in order to complete a successful rebuild.