Engine Nailing...Source???
01-25-2015, 09:56 PM
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1987 Mercedes 300d M603
Engine Nailing...Source???
Engine Nailing, probably injectors?
Hello all,
I am now trying to diagnosis the nailing sound in my 1987 Mercedes 300d. In the past, the car would nail in the morning and then everything would be fine once warmed up. Now the car has the nailing sound even when warmed up. Yesterday, I did a diesel purge (lubro moly) and while the purge was going it purred beautifully; no nailing or knocking! As soon as I hooked the fuel lines back up she started nailing again. I am wondering, based on the fact that the nailing went away during the diesel purge, that the culprit is one or more of the injectors. I am pretty sure that the injectors are original, so a rebuild is not out of the question. Now I am wondering a few things....
1. Since the nailing went away completely during the purge, can the cause of the noise be pinned down to the injectors themselves and not timing chain stretch, injection pump timing, etc.
2. What is the procedure to "roadside" check which injectors are nailing?
3. What is the potential damage that can be done to the car with the nailing?
I appreciate your help! The video below is a sample of the nailing that comes from the engine. In the video the engine was warmed up after a 45 minute drive, so it is not a cold start! Anything to help guide me is appreciated!
https://www.youtube.com/watch?v=IXt-...ature=youtu.be
Hello all,
I am now trying to diagnosis the nailing sound in my 1987 Mercedes 300d. In the past, the car would nail in the morning and then everything would be fine once warmed up. Now the car has the nailing sound even when warmed up. Yesterday, I did a diesel purge (lubro moly) and while the purge was going it purred beautifully; no nailing or knocking! As soon as I hooked the fuel lines back up she started nailing again. I am wondering, based on the fact that the nailing went away during the diesel purge, that the culprit is one or more of the injectors. I am pretty sure that the injectors are original, so a rebuild is not out of the question. Now I am wondering a few things....
1. Since the nailing went away completely during the purge, can the cause of the noise be pinned down to the injectors themselves and not timing chain stretch, injection pump timing, etc.
2. What is the procedure to "roadside" check which injectors are nailing?
3. What is the potential damage that can be done to the car with the nailing?
I appreciate your help! The video below is a sample of the nailing that comes from the engine. In the video the engine was warmed up after a 45 minute drive, so it is not a cold start! Anything to help guide me is appreciated!
https://www.youtube.com/watch?v=IXt-...ature=youtu.be
01-28-2015, 05:56 PM
#2
Out Of Control!!
Do yourself a huge favor and purchase a cheap auto sound probe and start probing your fuel pump--- cylinder by cylinder---then move to the injectors!!
