[plurant]

Hello everyone. Today i did the injector seals of my N47 F30, the car is from late 2012 and has 200K km's.

I had a small diesel fumes smell in the cabin when the car was stationary.
When i popped the hood i heard nor saw anything until i removed the sound insulation and cover.

Cylinder 3 was making a little pscht pscht noise and there was a little diesel around it (feed lines were dry).

I ordered the seals for all 4 cylinders and did the job the next morning.

All injectors started leaking but only number 3 had tar around it was the worst, i had to use a socket extender to wiggle on it and eventualy it came out. The best is to do this with a warm engine.

stuck injector
old seals
everything back in

took me about 3H for the whole job.
to clean the injector slot i used WD40, a drill brush of the diameter of the slot and a screw to block the injector hole to prevent dirt falling it the engine.
to extract the dirt you can use a plastic pipe on a vacuum so you can get into the head.

it's worth to have a look and do this when you car gets some mileage, if you drive with this issue for tool long the injectors can get permanently stuck in the head, contaminate oil and then it gets expensive !

And put some anti seize on the injector when you put them back in, mine were dry, i'm lucky i got them out !

[andreigbs]

This is a lot more common on older Mercedes diesels, it is known as Black Death.

Good thing you caught when you did, the mess it can result in is terrifying.