Is a 603 engine supposed to knock? - Page 11 - PeachParts Mercedes-Benz Forum

dannym · #**151** 08-09-2005, 07:29 PM

Awesome thread. lots of info here.
Honestly I didn't hear much difference in the audio files but my engine has the same type of rattle.
I know the PO babied the car but I don't.

I think I'll loosen some injector lines and see what happens. Also I'll try to find a shop to test and ballance the injectors.
I'll report back with results when I can.

I just wanted to mention the factory Shop Manual sates two different torque sequences for the delivery valves.
One is 30, 30, 35. The other is 35 ONCE.
You may want to look into that.

Danny

Marcb · #**152** 08-09-2005, 09:15 PM

Thanks for the feedback guys! I really appreciate your help and support through these projects!

Marcb · #**153** 08-18-2006, 10:23 AM

Well, after 1 year of chasing the "nailing" I finally went to another shop and they think I had one bad injector causing all of the nailing, pinging, knocking, etc. I can't believe it... I've had them tested by 2 other shops and both of them missed the *bad* one.

I guess I know which shop I'll be using for larger projects in the future! At this point, the car runs very nicely and I'm anxious to see if it'll last through several tanks of diesel. I just wanted to update everyone since these noises are so tough to diagnose.

AlanTbird · #**154** 08-23-2006, 10:29 AM

I've had mine for about nine months now and I've gotten used to all the idle racket!
Yours does not sound any worse then mine!
I think the vac pump adds to the mix!
Mine likes to "HUNT" at idle and that bugs me more!
cheers!

markg612 · #**155** 08-23-2006, 10:56 AM

I listened to your sound file, as well as some of the others. Mine has sounded like yours the 70K miles since i did the head and lifters. Hot in the summer it was nice and quiet, but cool or cold, it sounds just like yours always smooth, but just like yours UNTIL I Starton'd it. Now it's perfectly quiet, and my 606 is even better. It does the kind of purr/kackle thing, without the snap.

DieselAddict · #**156** 08-23-2006, 12:46 PM

Wow, someone dug up my old thread. I actually don't have this 87 300D anymore as you can see in my signiture. Sometimes I wonder if I should have kept it because in the last two years I've come across some fuel additives that work really well, like Amsoil's Cetane Boost and Diesel Fuel Additive Concentrate. My 240D was knocking a little bit at idle too and this combination of additives made it unbelievably quiet. I wonder what kind of a difference it could have made in the 87 300D. That car was a speed rocket compared to my non-turbo E300, but my Jetta is probably even faster.

markg612 · #**157** 08-23-2006, 01:27 PM

So were you questioning your 603 noise or your 606? I changed injectors in my 606 and it took about a month for them to settle in, quiet down and smooth out. The tips need to seat internally.

DieselAddict · #**158** 08-23-2006, 02:08 PM

Quote:

Originally Posted by markg612

So were you questioning your 603 noise or your 606? I changed injectors in my 606 and it took about a month for them to settle in, quiet down and smooth out. The tips need to seat internally.

I thought I made it very clear that this thread was about the OM603. I think I gave the injectors plenty of time to settle in. Looking back I think it could have been just carbon buildup in the prechambers, something that StarTron or Amsoil may have been able to fix. Oh well.