Alarming Sound?

[whereswaldo250]

Hey guys,
I have a few questions about a metalic sound that has gotten me wondering. I can hear it when the truck is idling and it speeds up as I raise the rpm. I can also hear it when I am driving drown the read but not very much. My truck is far past due for a valve adjustment and I am planning on doing it next week. I also know that my idle is a tad low, and will bump it also next week. Could it be a timing problem of a pre-ignition issue? I am just putting out ideas and you guys know a whole lot more then I know I hear some first gens and there is no other sounds but the nice rumble of the motor and others I hear have a whole bunch of noises.

Any Ideas whould be great

Thanks Ben

[Begle1]

If your timing was advanced enough that you're getting knock, I think it'd be a more alarming alarming sound.

Valve tick? My truck had a valve tick until I adjusted the valves a few thousand miles ago.

[MikeThomas]

Hey ben, you should get used to it...hehe. Do your valves first then listen. I think we become a little hper-sensitive to the MANY noises our trucks make and forget that it is a diesel. What sounds like a rod knock or piston slap in a gasser is, well thats just your truck belching out its sweet sweet melody. If you get overly concerned you should stop by we can take a look at it. I found that my piston lift pump really quieted things down.

[Paccool]

Describe the sound a little more. Is it a banging type noise? Is it a scraping type noise? What area of the engine does it seem to be coming from?

Depending on what type noise it is, could be several things. When my flex plate was failing, I first thought it might be rod knock but as it got worse, I could tell where the noise was coming from.

Could be injector noise, fan or water pump bearings, belt tensioner, even a fan belt but again it depends on what type noise you are hearing.

[whereswaldo250]

Thanks Mike I may just take you up on that offer of getting together, I'd like to listen to your truck again for a comparison Send me a PM sometime. The noise is coming from the top of the motor, but I can also hear it under the truck, but the sound could be bouncing off the engine bay, and making it more pronounced. It is like clicking two wrenches together, if that helps any. Like I said that sound could be a querk in my truck and maybe nothing is wrong. I'm sure everyone's truck sounds a little different

[MikeThomas]

Im not even being facetious, but I have that noise too, even after the valve adjustment and new lift pump...I think its just a cummins thing . Any way, come buy and stick you head under the hood and take a gander.

[whereswaldo250]

Yeah it must be, thanks Mike I sent you a PM

[JimmieD]

Im not even being facetious, but I have that noise too, even after the valve adjustment and new lift pump...I think its just a cummins thing . Any way, come buy and stick you head under the hood and take a gander.

Well, that makes 3 of us! I was sure a valve adjusment would quiet things down. It did, now it rattles entirely different Hah! When you break those wrenches out don't forget the dowel pin, and Loctite for the timing case to block bolts.