E420, 97, ease of pulling injectors
 

My grandma's 97 E420 has an injector that's leaking. Looks from the part that goes into the head. How hard are the injectors to reseal?? What is involved in pulling them?? Are any special tools required to take out the fuel rail and the injectors from the engine??

Of course working with gasoline requires extreme caution!!
Cold engine & bleed off fuel pressure.
Clean or blow dirt from the work area.

Other than that just basic remove bolts.

Make sure to have new o-rings for both ends.

I turned the key on the car to the on position, and there was a fuel leak from one of the injectors. I didn't start the car. Do the injectors usually need rebuilding when that happens, or would it just be needing resealing with new orings?? I was unable to determine the exact location of the leak.

I put new orings on the injectors today... The injector is still leaking. Can the injectors be rebuilt to stop the leak, or do I need to get 8 new ones?? Could one new one be bought and balanced to the others??

So, on the advice of an injection specialist friend of mine, I replaced only the leaking injector. Car runs just fine. No signs of the engine hammering on one cylinder, etc...
If one cylinder was hammering, he told me to replace the rest...