injector noise vs injector pump noise?

[jmccart]

Hello. My truck was making a noise that was like a tack hammer hitting something metal at a fast rate. It was seeming to come from right behind the top of the grille. Sometimes I seem to hear this noise at idle. Other times I hear nothing. ANy tips for me?



Thanx.

 

[JEstes]

How loud is it? I'm betting it's just your injectors firing. Somebody correct me if I'm wrong, but the injection pump usually doesn't make any noise if it starts to go bad. You'll just notice the engine running a little funny. If you really want to know if it's an injector or not, just shut the truck off and turn the key back to the run position. Listen carefully, and you should be able to hear the capacitor on the #1 injector firing. It sounds alot like a peizo grill ignitor.

 

[BradyWilliams]

It usually is not of any concern. If it gets worse then maybe. That has been noticed on MANY 3rd gen trucks. Thanks

 

[JTeague]

The noise you describe is comming from the injector pump gear rocking back and forth on the cam gear. The pump is not timed from the factory and in certain situations it is timed in just the right spot where the pump and cam are not "in-sync" so to speak. You can help this problem by loosening the pump gear and moving the pump shaft about 20 to 30 degrees and the noise should either go away or be alot quieter. I have had several people complain about this and have gone so far as replaced the cam and pump gear to help the problem before tring this. I talked to one of the instructors at DC and he said they are aware of the problem and have now timed the pump on the 6. 7 to correct the condition. I personally think theproblem is also aggrevated by the use of staight-cut gears on the pump and cam instead of the wider angle cut gears on pre common rail engines. The earlier design is far superior.

 

[jmccart]

I appreciate the help you all. Today I got home and I parked wtih the bumper as close as posible to the garage door, put the window down, and I could barely hear the noise. Weir.



Thanx again.

 

[JEstes]

JTeague,



So basically, it's a harmonic vibration of sorts that sometimes occurs when the cam and pump happen to be assembled just the right way?

 

[Snoxracer]

I was just going to ask the same question, I noticed the exact same thing with mine. I might have to try and move my pump gear 20-30* like JTeague said.

Thanks Guys!!! Man I love this site!!



Snoxracer



Also I was going to say, I usually just notice it during cold start up, and maybe just a little sometimes once it is warm.

 

[jmccart]

The noise you describe is comming from the injector pump gear rocking back and forth on the cam gear. The pump is not timed from the factory and in certain situations it is timed in just the right spot where the pump and cam are not "in-sync" so to speak. You can help this problem by loosening the pump gear and moving the pump shaft about 20 to 30 degrees and the noise should either go away or be alot quieter. I have had several people complain about this and have gone so far as replaced the cam and pump gear to help the problem before tring this. I talked to one of the instructors at DC and he said they are aware of the problem and have now timed the pump on the 6. 7 to correct the condition. I personally think theproblem is also aggrevated by the use of staight-cut gears on the pump and cam instead of the wider angle cut gears on pre common rail engines. The earlier design is far superior.

This is good JTeague. I don't quite get what I have to do to movethe gear 20-30 degrees.

 

[CraigJones]

My truck has been making this noise since 60,000 miles. I brought in too several dealerships with no results. I have replaced the FCA,cascade valve and my injectors and I still get this noise. When I put on my Quad box its makes this noise even louder. I have been saying all along that I thought it was the CP3 pump. FYI-Its not the box because I put this box on my buddy's truck and he gets no noise,also I put his quadbox on my truck and I get the noise. I am going to have to try this fix. Is this time consuming or can I do this in a hour or two ? Is there anyway you can PM me with a little more detail instruction on how to do this? Thanks.

 

[jmccart]

My truck has been making this noise since 60,000 miles. I brought in too several dealerships with no results. I have replaced the FCA,cascade valve and my injectors and I still get this noise. When I put on my Quad box its makes this noise even louder. I have been saying all along that I thought it was the CP3 pump. FYI-Its not the box because I put this box on my buddy's truck and he gets no noise,also I put his quadbox on my truck and I get the noise. I am going to have to try this fix. Is this time consuming or can I do this in a hour or two ? Is there anyway you can PM me with a little more detail instruction on how to do this? Thanks.

Has your noise gotten louder with time? I don't like the noise. But if I am told that it does not hurt anything I will at least be comfortable with it as just a noise and not something that will hurt my motor.



I have been really busy, so I have not done much searching. But I want to understand the 20-30 degree gear shift thing.



Thanx people.

 

[DEvery]

I also have the knock and would love to hear more about the procedure for timing the pump and cam gears.



Thanks

 

[jmccart]

I also have the knock and would love to hear more about the procedure for timing the pump and cam gears.



Thanks

We need you CraigJones.

 

[sag2]

The procedure is as follows.

Put a paint mark on the pump shaft and gear. Remove the drive gear nut and gear and rotate the pump shaft clockwise by hand about 30 degrees. Verify the paint marks are now 30 degrees apart. Re-install the gear and nut and start engine. If noise is still the same, repeat by moving another 30 degrees. If noise is not changed at 30 or 60 degrees the cause is not from the pump gear rocking on the gear train.

 

[CraigJones]

I will try to get this fix done in the next two weeks.

 

[jmccart]

I still have not forgotten about the info you guys have been nice enough to share. I still need to make myself understand it completely and check it out. Sometimes I hear the ticking big time, and other times it is hard to hear. I am a busy dude.



Thanx.

 

[CraigJones]

I did and no luck for me. If I get on it pretty hard and then back off but still give it light throttle I get knock still. This has been going on for 100,000 miles so I don't think its hurting anything but it is annoying. I have replaced my pusher pump with a glacier 392 pump, added 20 micron and a 2 micron filter(plus my stock fuel filter), replaced FCA,replaced cascade valve(overflow),replaced my injector with F1's and have tried every additive under the sun. I still think the problem is a timing issue and it caused by my ECM or something between the CP3 pump or what ever controls the fuel that goes into each injector. Anybody have any suggestions ? Thanks.

 

[jmccart]

I did and no luck for me. If I get on it pretty hard and then back off but still give it light throttle I get knock still. This has been going on for 100,000 miles so I don't think its hurting anything but it is annoying. I have replaced my pusher pump with a glacier 392 pump, added 20 micron and a 2 micron filter(plus my stock fuel filter), replaced FCA,replaced cascade valve(overflow),replaced my injector with F1's and have tried every additive under the sun. I still think the problem is a timing issue and it caused by my ECM or something between the CP3 pump or what ever controls the fuel that goes into each injector. Anybody have any suggestions ? Thanks.

It has been going on for 100,000 miles, that is good news. I just want to know that it is OK to ignore.