m127: Oil pump

[pagodarune]

I have bought a new original oil pump to replace my broken one. When inspecting the new oil pump I noticed that it has a lobe on the drive shaft which the old one does not have, see attached pictures. Does anyone know the function of this lobe? Is it some sort of balancing?

[Cees Klumper]

From the picture it looks like the lobe on your old pump has broken off.

[pagodarune]

It is correct that the end of the drive shaft is broken off on the old pump. That is the reason it has to be replaced. But if you look below the part that is broken, the old shaft is round while the new shaft has a lobe. I have attached a picture of a replacement shaft for the old pump (which I decided not to use). You can see that the replacement shaft has no lobe.

[mbzse]

.../...it has a lobe on the drive shaft.../... Does anyone know the function of this lobe

This is for running the mechanical fuel pump on M108 and M130V (carburetted M130) Mercedes engines.
These use the same oil pump type as M129/M130E engines
/Hans in Sweden
.

[ja17]

Yes, Hans is correct. The cam will serve no purpose in the fuel injected engine of yours. It causes no harm.

[pagodarune]

Thanks Hans and Joe. I learn something new about these cars everyday.