Applies to all 110 115 116 123 126 201 124 140 diesels from 1961 to 1994. From my many years of working professionally on Mercedes diesels I have learned fuel injectors are the single most neglected maintenance item. I believe there are a number of reasons for this. Partly it may be the mystery surrounding how injectors work and what needs to be done to service and repair them. Then there is the false notion that like the engine they will last forever. And finally, it can be very expensive to have a shop replace the fuel injectors. You may even have said to yourself, the engine seems to be running fine so why bother spending the money?
Mercedes diesels are amazing. Short of catastrophic failure they just don't want to die. They seem to keep running acceptably even with worn camshafts, weak compression, high oil consumption, improper engine timing, and worn out fuel injectors. Fuel injector failure is very subtle. It happens slowly over a period of time with the symptoms being: harder cold starting, more exhaust smoke, less power, and decreasing fuel economy.
I made a commitment to help diesel owners with this important maintenance issue. If one can rebuild his own injectors he can save hundreds of dollars over having a shop install new or rebuilt units. Even if the injectors are in good condition they do need periodic cleaning for top performance.
My first goal was to un-cloud the mystery surrounding a diesel fuel injectors operation, cleaning and adjusting procedures. I did this with the writing of this manual. It covers the following topics and is illustrated with 40 pictures and bound with a smudge resistant cover:
- Tools required
- How to remove them from your engine and replace them
- How to take apart and properly clean the injector parts
- How to determine if they are worn out
- How to install new nozzles
- How to properly put them back together
- How to bench test them for proper sealing and release pressure
- Injector parts breakdown
- Pressure specifications
- Advantages of Monark injector nozzles
- Resources for testers and adjusting shims
- SVO / WVO cautions
- 10 copies of Kent's testing chart to be used during bench testing
This is a must have guide for every diesel owner. It covers injectors in 220D 240D 300D 300CD 300TD 300SD 190D 300SDL 350SD and 350SDL models as well as others of the same period. Even if you do not plan to rebuild your injectors yourself, understanding how your injectors work and what needs to be done to maintain them, will go a long way toward keeping your diesel performing in tip-top shape.
My second goal was was to provide a set of affordable cleaning tools geared for Mercedes injectors that really work. I have done this with the introduction of the Mercedessource Injector Cleaning Kit (look below to order). Thirdly, I knew I had to deliver a set of high performance injector nozzles to our customers at an affordable price. I have been able to do this with the high quality German Monark injector nozzles that we import and now sell on our website (type nozzle in the search box to view all Monark nozzles). And finally, I have delivered on my promise to produce an inexpensive injector balance tester that can be easily set up and used by the home mechanic. Now there is no reason not to overhaul and service your fuel injectors yourself (see below for pressure tester).
I recommend you have a torque wrench handy when rebuilding your injectors. If not we offer one at a great price. Look below to order.