I posted up here a couple months ago, and in that thread I found that what ever was making the sounds that I didn't like was contributed by the new injectors that I had installed.
With these new injectors, it made a weird sound, only under load that I would have described as a similar sound to a gas v6 engine exhaust manifold leak. The sound sounded air related, maybe even like the valves were out of spec. I checked valves a few times and they are at perfect Cummins Spec.
I swapped back to the factory injectors that I had and everything sounded perfect in the engine once again.
I'm having trouble with hands on communication with the injector company that I've done business with and frankly I am a noob when it comes to this sound.
Right now, my truck has upgraded fuel plumbing, keeping 25 psi at idle and keeping north of 30 psi up to 45 psi while driving.
With the factory injectors, they have about 200k miles on them from what I know, and they do seem to be going out if I were to give my uneducated guess.
These new injectors are 5x14 SAC with the edge filter removed and needle work. New Bosch Nozzles on New Bosch Injector Bodies.
I sent them back to be looked at by this company 2 months ago and just received and installed them this week.
Anything below 1,800 RPM I can hear this sound in the cab very easily. Up to 2k I still hear it but it's not as prominent. From 2k to 3k even under load accelerating up a hill, the engine sounds perfect.
Is this just something to do with timing, and not the injectors themselves? I keep reading about Injector Rattle but I can't find a video to understand if that is what this is.
Is this a sound that I'm hurting the engine?
Also to add:
The engine starts up fine. In Park or Neutral the engine idles as the same RPM that the factory injectors Idled at.
Only when the engine is cold, do these new injectors drop to a lower RPM than the factory ones once I put the truck in gear with the first start up.
2 Months ago when it was much colder out (40-50*F) it would drop low enough to lope. Now (70-80*F) after I received the injectors back it doesn't lope, but does drop more RPM than the factory ones have been.
With these new injectors, it made a weird sound, only under load that I would have described as a similar sound to a gas v6 engine exhaust manifold leak. The sound sounded air related, maybe even like the valves were out of spec. I checked valves a few times and they are at perfect Cummins Spec.
I swapped back to the factory injectors that I had and everything sounded perfect in the engine once again.
I'm having trouble with hands on communication with the injector company that I've done business with and frankly I am a noob when it comes to this sound.
Right now, my truck has upgraded fuel plumbing, keeping 25 psi at idle and keeping north of 30 psi up to 45 psi while driving.
- 4k GSK
- S362 SXE
- 18* Timing
- O-ringed Head
- Hamilton Valve Springs and Pushrods
With the factory injectors, they have about 200k miles on them from what I know, and they do seem to be going out if I were to give my uneducated guess.
These new injectors are 5x14 SAC with the edge filter removed and needle work. New Bosch Nozzles on New Bosch Injector Bodies.
I sent them back to be looked at by this company 2 months ago and just received and installed them this week.
Anything below 1,800 RPM I can hear this sound in the cab very easily. Up to 2k I still hear it but it's not as prominent. From 2k to 3k even under load accelerating up a hill, the engine sounds perfect.
Is this just something to do with timing, and not the injectors themselves? I keep reading about Injector Rattle but I can't find a video to understand if that is what this is.
Is this a sound that I'm hurting the engine?
Also to add:
The engine starts up fine. In Park or Neutral the engine idles as the same RPM that the factory injectors Idled at.
Only when the engine is cold, do these new injectors drop to a lower RPM than the factory ones once I put the truck in gear with the first start up.
2 Months ago when it was much colder out (40-50*F) it would drop low enough to lope. Now (70-80*F) after I received the injectors back it doesn't lope, but does drop more RPM than the factory ones have been.
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