DDP 90's went in and now have a rattle, need advice

Marco said:
I believe we're talking about two different rattles at the same time.

One is "timing rattle" which is increased combustion noise.
Of course, the get rid of the timing rattle, reduce the timing and voilà. Only consider that without increased timing a lot of performance remains on the table.

"Injector rattle" like the one I've heard in Sam's truck is a different beast.
I could hear ( very distinct ) the single injectors firing. OK, I'm getting old and I may not hear as well as when I was younger but I would swear that the truck I rode in had only 2 maybe 3 injectors in it that did this " rattle". ( That's IF it is caused by the injectors...)

My offer still stands. IF it is possible to make it happen. None has a spare set of injectors to use while I do my thing?

Marco
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Man I wish Big Swole would have mentioned this when you were state side, Marco we have a pretty big Dyno event this weekend in PA, I know it would be hard for ya to make it but you would have at least 2-3 different trucks that have this issue going on to work with. Be nice to have ya at the dyno but we would have to lock you in the building while you do your thing!LOL
 
Marco.

Injector rattle is not the problem most of us are facing. Inj. rattle doesn't go away with boost / cylinder pressure.

This rattle we have ( call it timing rattle ) does go away ( or severly reduced ) with boost / rpm...

Its right off idle (0-10 or 15 psi of boost) then gets reduced...

If its bad Marco, it sounds almost like a ball bearing rattling around inside the cylinder until boost comes up..

My decompressed motor would litterally Echo off everything around my truck (cars, trucks, walls, buildings, etc)....It was flat out embarrassing..
 
and it does not happen on every truck with the same injectors, what rattle for me on an 04.5, might not rattle at all on your truck. I dont think it is as much boost related as it is rpm related, maybe at the point when the pilot injection stops the rattle goes away. I can roll boost to an rpm with rattle, and the rattle is still there. worst part is at cruise on the highway, just listening to it constantly bangin away, like swole said, a bearing inside trying to get out.
 
was talkin with swope and had an idea, I know we cant kill the pilot injection event, but why not kill it earlier, say at 800 rpm? this way we get all the fuel when we want it, and none when we don't. It would still be there to smooth out idle and thats it.
 
OK, looks like my problem is to understand what rattle we're talking about.

IF it is the rattle like what I've heard in Sam's truck... well, that's NOT timing rattle. David, is the rattle like Sam's?

I'm a newbie to this problem / rattle so for now I'm simply not taking into account the more exotic possible reasons like pilot injection. In my opinion, it's something simple / stupid that's causing this.

Marco
 
mikmaze said:
was talkin with swope and had an idea, I know we cant kill the pilot injection event, but why not kill it earlier, say at 800 rpm? this way we get all the fuel when we want it, and none when we don't. It would still be there to smooth out idle and thats it.
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Isn't 800 rpm a little low for some trucks? Why not kill it around 950-1000 rpm?
 
750 is normal idle, in my mind there is no need for it after that. If it is indeed something simple causing this Marco, that's good, 'cause it should be a simple fix. I wish you had a chance to see/ hear it while you were over here in the states.

yeah mine did it with 100's, and with 175's it bad.
 
Marco mine is exactly like Swole described, right of idle and once boost hits 5psi or so its gone, plus ine only dose it one the engine starts gettin up to operating temps, when its cold its quiet as a mouse!!
 
come on guys I know more than just a couple of us have this issue, and most likely want it looked into, so if you have something along these lines of the described rattle, by all means post up so Marco and Bob see that it is worth looking into. Marco if you have any tips or insight on any of the simple fixes, by all means let us know. I will say this, it is consistent, I had it with the flux 2's and a single cp3 with arson 3 kit stock lift pump, and then with the air dog also, and flux 3.5's on the single cp3, and now with the two cp3's so not a fuel supply issue.
 
Marco,

I guess I'll have to get with Sam the next time I see him and his truck... He did not used to have the issue when he had Flux 3.5's... I thought He did have it now with the 4.5's he has now..

But I can assure you that MANY trucks have what I described... Many!
There are several old threads about this..Triton started some way long ago..Then I did too after my first build..

4 motors later... I still have it...

Deffinately pilot inj. related in my Opinion..
 
& to add, there is no setting that I can find on the smarty tnt R that makes it go away, tried all levels of torque management, all levels of timing, and all levels of rp. the disturbing part of it on my truck is that when it is rattlin, and ya try o give it a little more gradual fuel, it feels like the truck is hesitating like that pilot shot is too powerful for the upward travel of the piston at that point.
 
The rattle described is in the injector, not the programming. Some have it more than others because of each individual injector's calibration and ability to respond to commands at very short clock times. With stock flowing nozzles, this is not a problem. As the nozzle flow increases, its ability to inject fuel at lower "on-times" can decrease because the pressure drop in the nozzle is so fast. This has to do with discharge coefficients being so much higher than stock values and a heavy pintle. Honed nozzles have very high CD's. I have shown graphs of this problem in the past on this forum.

Part of the solution we have come up with is changing the tuning toward the rich side of calibration for excitation times in the 200 to 300 microsecond range. This is a big undertaking in terms of time, but can be completed as part of a normal injector reman at time of assembly. Lower CD's and lighter pintles also help. Remember that the pressure in the rail is secondary to the pressure inside the nozzle. If you cant keep the pressure up inside the nozzle, the injected quantity begins to drop and big spray holes coupled to low solenoid on times drops the pressure like a stone.

I would be willing to try and tune out rattle for a few people on a pilot program to get a good solution. I think our existing customers would be the best place to start.

Mike?
 
Soup Nazi said:
The rattle described is in the injector, not the programming. Some have it more than others because of each individual injector's calibration and ability to respond to commands at very short clock times. With stock flowing nozzles, this is not a problem. As the nozzle flow increases, its ability to inject fuel at lower "on-times" can decrease because the pressure drop in the nozzle is so fast. This has to do with discharge coefficients being so much higher than stock values and a heavy pintle. Honed nozzles have very high CD's. I have shown graphs of this problem in the past on this forum.

Part of the solution we have come up with is changing the tuning toward the rich side of calibration for excitation times in the 200 to 300 microsecond range. This is a big undertaking in terms of time, but can be completed as part of a normal injector reman at time of assembly. Lower CD's and lighter pintles also help. Remember that the pressure in the rail is secondary to the pressure inside the nozzle. If you cant keep the pressure up inside the nozzle, the injected quantity begins to drop and big spray holes coupled to low solenoid on times drops the pressure like a stone.

I would be willing to try and tune out rattle for a few people on a pilot program to get a good solution. I think our existing customers would be the best place to start.

Mike?
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If the time frame is not too long I can send my flux 4.5 in from my 04.5 ?? thanks Rob Also has anyone posted a video of the said rattle??
 
Some never get this rattle because every injector is slightly different from the factory. Bosch cant spent hours tuning each injector and the way they leave the factory is fine for stock flowing and stock CD nozzles for the 03-07 5.9's.

This slight difference in all injectors when manufactured is what the 6.7 calibration codes are all about. Bosch measures each injectors output and its response. They can then provide calibration information for each injector. This allows the 6.7 ECM to be programmed to each injectors "curve". Instead of spending untold hours tuning each part, the ECM can be tailored. This is why you want to get your same injectors back in the cylinders they came out of in the 6.7. Some of the 6.7 injectors we see are so far apart in terms of calibration it is crazy.
 
rpainter said:
If the time frame is not too long I can send my flux 4.5 in from my 04.5 ?? thanks Rob Also has anyone posted a video of the said rattle??
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Do you have the rattle? Got a video or audio file? Just wondering if we could do some "before and after" results kinda thing here.
 
Soup Nazi said:
Do you have the rattle? Got a video or audio file? Just wondering if we could do some "before and after" results kinda thing here.
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I have a slight rattle at idle when the motor is cold. heard a lot talking about it but noone has very posted on video or sound clip so I can compare?? Everyone said that big injectors and lower compression will make it worse. I am running the flux 4.5 and 15:1 compression on my 04.5.
 
Hope the guys with DDP's can get some support after the Flux's guys get er figured out....
 
rpainter said:
I have a slight rattle at idle when the motor is cold. heard a lot talking about it but noone has very posted on video or sound clip so I can compare?? Everyone said that big injectors and lower compression will make it worse. I am running the flux 4.5 and 15:1 compression on my 04.5.
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Rattle when cold and lowered compression might be the issue, but I would still try and tune it out on my end.

Right now, I am covered up. This thing has consumed my life like never before. Its 7 days a week until I simply cant move, followed by a crash of at least one day, maybe two. I am knocking a huge dent in these back orders though. Once I clear them, lets get to work.

Anyone else have a stock compression truck with rattle?
 
Well All of my motors have been below stock compression at different levels..Current with monotherms is close to 16:1 I think... All my Injectors (tips 3.3's, 3.8's (old SAC style), New 3.8's (sent back) and now new 4.0's Bosch nozzles) have made the rattle ( slightly different due to compression)..

So I guess it's in my inj. bodies /solenoids... Timing issue Don's referring to...

Oh well!!

My truck is still down a will be for another few weeks...

At this point, I'm just chit outta luck I guess..

I just wanna drive my dang truck... rattle or not..
 
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