Hello, so I'm doing an A-Z to my 190d 2.5 from 89 and I just realized that it doesn't have a fuel pump nor fuel filter beneath the rear wheel where they usually are. It has a hand pump with a small glass filter in the engine though, going to the fuel filter.

So my question is... How does it pressure the fuel? Is it the injection pump?

Thanks!

An OM602 should not have a hand pump. There is a mechanical lift pump on the side of the injection pump, similar to how old carbureted cars operated. The high pressure for the injectors is created by the pumping elements inside the injection pump.

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Current stable:
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On my year and model if you trace the fuel lines you will find the inlet line goes through a small Plastic Filter then from there to the Fuel Supply/Lift Pump that is in the middle of the front 2/3rds of what is generally called the Fuel Injection Pump (it is blotted to the side and projects away from the side of the Fuel Injection Pump body). On mine the Hand Primer screws into the Fuel Supply/Lift Pump.
It is also made of Steel or Cast Iron.

On the Later Models the Fuel Supply/Lift Pump is in about the same position but is made of aluminum, smaller and there is no Hand Primer on it.

The main thing is the a Fuel Line goes into it and another Fuel Ling goes out of it to another Filter and from there a Fuel Line goes to the Front top of the Fuel Injection Pump.

On the opposite side but rear of the Fuel Injection Pump is another Fuel Line. What looks like a typical Banjo Bolt in side is a spring loaded valve. That valve is what hold the pressure of the Fuel Supply. The Fuel Supply/Lift Pump is what moves the Fuel.

That supplies the Fuel to the Elements inside of the Fuel Injection Pump. It is the Elements inside that create the high pressure for the Injectors.

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84 300D, 82 Volvo 244Gl Diesel

Don't know 1989 cars, but probably all engines w/ a Bosch injection pump (M-B, VW, tractors, ...) have a Bosch lift-pump on the side. I see new ones cheap on ebay that would bolt up, but inlet and outlet point the wrong way to work on my 1985 (would bump into K-frame). Worst-case, one could install an electric fuel pump, but I haven't heard anyone that desperate yet. Only needs ~12 psig outlet.

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1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
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