New injectors....How much rattle is normal?
 

I just had my injectors rebuilt back at the first of the year. The truck runs great, has more power etc and seems to get better mileage around town and about the same as before on the highway(20mpg+). It also idles fine. My problem is, now I seem to be hearing what i think is an injector rattling. It has been doing it some ever since the install but I figured that was normal. Lately, I can hear what sounds like 1 single injector that is louder than normal. It seems to get quieter when I accelerate and seems to completely go away when I let off of the accelerator. It's loudest at a constant speed. I do have a 2 micron fuel filter setup with the CAT 0750 filter. I also am running the stock filter. I change these religiously. I also have run standadyne in every tank that these injectors have seen. I have been draining my stock filter every other day into a clear bottle and have not been getting any visible contaminants, Just clear diesel.

Even though I have a lot of miles on the truck(over 200,000) I don't think it's a valve out of adjustment just because of the way it acts on acceleration/decelleration. Of course, I could be wrong.

How much rattle is normal? Is this something to worry about. I'm sure if its an injector issue that it will be taken care of but I hate to take it back if its nothing to worry about.

One thing in case it matters, I do have an Xzillaraider 2 on the mileage tune. When I turn it off, the rattle does get a little quieter but not much.

Thanks
Dave

Bump

Did you adjust or have the valves adjusted after the injector install? If not, you need to do it since you pulled the rockers off to get the injectors out. It is normal to have some rattle, it is more noticable in cold weather.

You might be hearing something that is very hard to hear with a Common Rail. That is the nut cracking sound you always heard in all the pre 2003 cummins engine. That could be what your hearing with the new injectors installed.

I hear it in mine once and awhile. Usually when cruising with no load on the engine around 50-55 mph. I have 50K on my 06.

It could also be as mentioned above, valve rattle.

Dave

This rattle is easy to hear. It is definitely getting louder. I am going to check the valve clearance this weekend just to rule out that being the issue. I still dont think it is the valves although I hope thats all it is. When I step on the throttle pretty hard I can hear the motor rattle pretty bad for a second or so when the extra fuel is dumped before the rpm comes up. I figure that is normal. The sound I have been hearing is just one single rattling sound and its pretty noticable. It does it constantly unless I let off the accelerator or if I mash it pretty hard. It probably is a little louder when the engine is cold. Wouldn't a lifter do it throughout the entire rpm range even when coasting?

Do you definitely have to pull the rocker arms to install injectors? I had it done by someone else. If he had to remove the rockers then I am sure he readjusted the valves correctly as he is pretty reputable. If the rockers did not have to come off then they probably need to be adjusted being I have a ton of miles on the truck.

This truck always seemed to have injector rattle even when it was new. I guess I finally got used to it. I took it back several times and was always told it was fine. I put about 200,000 miles on the stock injectors so they must have been ok. After having them rebuilt by F-1 and then installed the truck was quieter than it ever had been. It runs better too. Its just recently that this noise has come about. Before, it was like it had a rattle in all cylinders and now it sounds like its just in one.

Who knows? Hopefully I will figure it out.

thanks
Dave

Check all your injector line hold down clamps. The small clamps with blue plastic liners, if they come loose they rattle fairly loud, and will eventually break the injector line.

Good tip JJ

Yep, that is what I was going to say. Put some loc tite on the back of them, too.

I thought I had an injector dying, one day I got under the hood and started touching stuff with the engine running to see if I could isolate which one it was coming from... grabbed one of those little blue holders... :)

https://www.dieseltruckresource.com/...y-t258339.html

Pic at the bottom of the first page...

Thanks guys, I will definitely check out that possibility. I have seen the blue holders you are talking about but I did not look at them closely.

Dave

exhaust rockers have to come off to remove the injectors out, but they don't have to be adjust from removing them, your not changing anything if you don't touch the adjuster. they do however need adjusting if they were mixed up out of order, or if the just plain need adjustment due to wear or mileage.
i did my 03 with 420,000kms, and check them when going back together and it was bang on.

Pullin Hard,

Thanks for the info. That makes sense to me. I am going to adjust them and see if it helps.

David

Were the injectors brought back to stock or were any enhancements done? I put a set of Edge nozzles in my truck and it gave a pretty good timing rattle....

CR trucks especially the '06 -'07 5.9's have a rattle under light to moderate acceleration that is quite bothersome at times but normal. If it goes away when you let off and when you push harder it is the nature of the beast.

The injectors were upgraded to flux 1's. NickBeek, I agree with what you are saying. The only thing is that it's not a rattle that seems to come from all cylinders or injectors like I am used to hearing. It's definitely just one that is making the loudest noise.

David