clattering noise..

[kayla j]

I got my truck back yesterday after having a used motor with 65k put in the truck because i cracked both my heads in a family emergency run. When i got the truck back yesterday i left and gave it gas or when it is at high RPM's it sounds like a loud clattering noise.. not like something is loose and rattling. Sounds like a valve or something.. If you have any suggestions at all please feel free to give them to me! All help is appreciated

 

[dmaxn04]

She is referring to a sound almost like valve clatter.. It only does it under about 1/4 throttle acceleration or when its around 3k rpms... Its wierd because the old motor did something very similiar sounding.. The motor runs smooth, just has that clatter.. Could it be anything to do with fuel delievery? Like a weak injection pump causing some type of clatter or anything?

 

[Josh2002cc]

Any smoke out the tailpipe? Do you lose coolant?

 

[dmaxn04]

Any smoke out the tailpipe? Do you lose coolant?

No smoke out of tailpipe, and the coolant doesn't leak or build pressure. They just had a complete Longblock put in with only 65k miles on it. Truck runs better then ever besides this clattering noise. Like i mentioned. It did it before with the old motor but not as bad. This motor does it louder and at partial throttle when accelerating also. Sounds like a loud valve clatter noise... Doesn't do it the whole time truck is running.. Just certian rpms and certian amounts of throttle.

 

[stroke250]

wonder if it is injector related, maybe harness issue????

 

[RENODMAX]

Is it tuned

 

[MMLMM]

Is it tuned

x2, injector/timing rattle?

did you use old ecm with this motor, or a new ecm?

 

[JoshH]

Sounds like maybe a tuning issue to me.

 

[dmaxn04]

Truck has no tune on it. The old ECM off old motor was used on the motor that was just put in.. Is that bad?? Do you guys think its possibly tuning because the old motor did it also?? It just doesn't sound right. And the old motor only did it when you would floor it and it was at high rpms.. This new motor is doing it when taking off from dead stop at like 1/4 throttle and also does it if you floor it, it does it at high rpms like the old motor did. Truck doesn't throw any codes.. And it actually runs really good, it just had that clatter at certian rpms and throttle amount.

 

[mytmousemalibu]

Ok, after reading the above:

Since it did it on the old motor too, Give a new fuel filter a try, at least get that out of the equation. As a suggestion, from personal experiance, alot of the stock fuel filters for our trucks changed to the newer, updated design, including the AcDelco one. I had problems with the updated ones, i belive they are too restrictive and caused fuel starvation and that produced a rattleing sound at certain RPM's. With the old type filter, I had no issues. The current filter I run is a Baldwin, the old type still. I would recommend one! To tell "old" VS "new".... the new type has 4 kidney bean shaped holes in the middle......crappy
The good old type has 2 rows of holes, horizontally in the sides of the inside edge. Make sure that your plastic filter bleeder screw is in good shape and not broken/cracked. And also no fuel around the primer pump

Baldwin# BF7827

Attatched a picture of the old "good" type filter!


Since these trucks have no electric pump to help feed the main pump, it has to suck the diesel all the way from the tank and through the filter and to itself, so a dirty/restrictive filter=problems

(my problems i learned from were all before i installed had a lift pump on mine)

 

[dmaxn04]

Ok, after reading the above:

Since it did it on the old motor too, Give a new fuel filter a try, at least get that out of the equation. As a suggestion, from personal experiance, alot of the stock fuel filters for our trucks changed to the newer, updated design, including the AcDelco one. I had problems with the updated ones, i belive they are too restrictive and caused fuel starvation and that produced a rattleing sound at certain RPM's. With the old type filter, I had no issues. The current filter I run is a Baldwin, the old type still. I would recommend one! To tell "old" VS "new".... the new type has 4 kidney bean shaped holes in the middle......crappy
The good old type has 2 rows of holes, horizontally in the sides of the inside edge. Make sure that your plastic filter bleeder screw is in good shape and not broken/cracked. And also no fuel around the primer pump

Baldwin# BF7827

Attatched a picture of the old "good" type filter!


Since these trucks have no electric pump to help feed the main pump, it has to suck the diesel all the way from the tank and through the filter and to itself, so a dirty/restrictive filter=problems

(my problems i learned from were all before i installed had a lift pump on mine)

Ill put a new filter on it and see what it does. On the old motor I loaded a buddies ppe standard up on it to see how it ran and even with the aftermarket tuning on the old motor it did that same clatter at high rpms even with the aftermarket tuning, so it has to be some kind of issue with fuel or something?? I think they may of used the old injection pump off the old motor and put it on the new motor that was just put in. On a Dmax, where is the injection pump mounted? I have not played with the 6.6L enough to know where everythings at..

 

[mytmousemalibu]

Ill put a new filter on it and see what it does. On the old motor I loaded a buddies ppe standard up on it to see how it ran and even with the aftermarket tuning on the old motor it did that same clatter at high rpms even with the aftermarket tuning, so it has to be some kind of issue with fuel or something?? I think they may of used the old injection pump off the old motor and put it on the new motor that was just put in. On a Dmax, where is the injection pump mounted? I have not played with the 6.6L enough to know where everythings at..

Ya, adding more power tends to make a starvation rattle louder or more often, etc. Now the Bosch CP3 common rail injection pump that the Duramax engines use is located in the valley of the motor, its kinda hard to see with all the other stuff still there. Most likly, if the injection pump is weak, its going to be giving a check engine light, codes like low rail pressure, etc, and prolly going to be having more severe issues.

Is there any lights/codes?
Does the truck feel sluggish?
Any smoke?
Leaks?
Other than the noise, any thing else abnormal?

 

[dmaxn04]

Ya, adding more power tends to make a starvation rattle louder or more often, etc. Now the Bosch CP3 common rail injection pump that the Duramax engines use is located in the valley of the motor, its kinda hard to see with all the other stuff still there. Most likly, if the injection pump is weak, its going to be giving a check engine light, codes like low rail pressure, etc, and prolly going to be having more severe issues.

Is there any lights/codes?
Does the truck feel sluggish?
Any smoke?
Leaks?
Other than the noise, any thing else abnormal?

Gotcha! No theres is no lights or codes. Truck doesn't smoke idling or under throttle. No leaks that I can smell or see.. The truck runs very good and like it should. Theres just that clatter noise. Its going back to the mechanic this weekend. Just was tryin to get it fixed myself if I could..

 

[MMLMM]

If you used the old pump, maybe the FPR is causing issues.

Any way to get any type of logs, or a quality sound clip at least?

 

[mytmousemalibu]

Keep us posted

 

[JoshH]

What you're describing sounds like timing rattle to me. The stock tuning on our trucks have several different timing tables that they run off of. The ECM selects the correct table by looking at barometric pressure. Being in MS, you should probably be running in timing table C, which is the most conservative, but since the motor has just been swapped the barometric pressure may have been damaged or a wire could have been damaged. I see EFILive in your sig. Try hooking up your scan tool and see what everything looks like.

 

[dmaxn04]

If you used the old pump, maybe the FPR is causing issues.

Any way to get any type of logs, or a quality sound clip at least?

Im not sure if they used the old pump, I don't think they did.. Im pretty sure they used the pump that came on the new motor, because it was a complete long block, minus alternator and a/c compressor thats it..

I have efi live.. I could log it, what should I log though?

 

[dmaxn04]

What you're describing sounds like timing rattle to me. The stock tuning on our trucks have several different timing tables that they run off of. The ECM selects the correct table by looking at barometric pressure. Being in MS, you should probably be running in timing table C, which is the most conservative, but since the motor has just been swapped the barometric pressure may have been damaged or a wire could have been damaged. I see EFILive in your sig. Try hooking up your scan tool and see what everything looks like.

If a wire were tore up or damaged, wouldn't it trip a code? What should I log? I know what timing rattle sounds like, this is not it. A buddy has a 05 LLY and his sounds nothing like this..

 

[JoshH]

Barometric pressure, timing, fuel pressure (actual and desired), fuel quantity, injector pulse time, RPM, and pilot injection quantity would be a good start.

 

[RENODMAX]

Sounds like maybe a tuning issue to me.

Bingo. My stock tune rattles