Another Knocking Sound Thread

[WarNose]

i just replaced my injectors because the motor was making a ton of noise. I also put new return lines. The motor runs a lot smoother but it is so quiet now that I hear a knocking sound that I couldn't pin point before. I'm afraid its a rod knock at the rear drivers side of the motor. Here are a couple of links to videos of the motor running. You can hear it best when the camera is under the truck looking at the starter. What do you all think? Thanks for the help.

https://youtu.be/qHd21rRRbVE

https://youtu.be/2TJG92nYc9Y

 

[MTKirk]

Check to see if your accelerator cable is resting on your injector line (drivers side near the firewall). Super easy fix if you're lucky enough that it's your problem.

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[larson]

Check to see if your accelerator cable is resting on your injector line (drivers side near the firewall). Super easy fix if you're lucky enough that it's your problem.

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How does that fix the problem? Just curious.

 

[icanfixall]

Please tell us where you purchased the injectors and were they new or rebuilt.

 

[crash-harris]

How does that fix the problem? Just curious.

The cable will knock against the injector line. We've had that happen here rather recently.

 

[WarNose]

They are R and D injectors. Rebuilt with new pintles.

 

[icanfixall]

They are R and D injectors. Rebuilt with new pintles.

Oh.... Might send them back mentioning you have a knock. No matter what. ANY injector can be bad from the start. This forum has seen new right out of the box fail because they had metal shaving in them. It has been the norm to have any injector pop tested before it goes in the engines. Also keeping things surgically clean helps to insure you did not get dirt into the injector. I use white rubber gloves and if the get dirty I change them when doing injectors. Using a few sets of gloves is cheaper than pulling a dirty ruined injector.

 

[Waystro]

Didn't another member have problems with his R&D injectors not to long ago?

 

[icanfixall]

Didn't another member have problems with his R&D injectors not to long ago?

Yes.....

 

[crash-harris]

Now I'm glad I went with Russ

I've been using nitrile gloves for injector work. Easier to keep the box close and go through a few sets of poweder-free gloves then to have to do things over again.

 

[WarNose]

So the sound is definitely the loudest through the oil pan. Is that where I would hear an injector knock from? That's what has me worried that it couldbe a bearing. I was very careful about keeping the injectors clean.

 

[icanfixall]

So the sound is definitely the loudest through the oil pan. Is that where I would hear an injector knock from? That's what has me worried that it could be a bearing. I was very careful about keeping the injectors clean.

Sadly you just can't say the injector has not failed. Surprising as it is.. When an injector has a problem like a weak spring for unknown reasons. The engine will knock horribly because that injector is injecting fuel really really causing a fuel knock. It really does sound like a rod knock. Sorry I can't tell you for certainty that you do not have a rod knock. I just can't hear that well any more and listening toa vid is really ruff.

 

[crash-harris]

Crack the injector lines loose one at a time near that side of the block and observe if one of them causes the knock to stop. That would tell you if it is an injector.

 

[WarNose]

Thanks for all the advice. Ill crack open the injectors and see what happens.

 

[WarNose]

So I cracked each of the injector lines and the knock did not go away. But on the number 8 injector (closest to the firewall on drivers side) it did seem to get quieter but not fully go away. This makes me think that it is a rod knock since there would be less load on the rod without that cylinder firing. Or maybe it was more than one injector knocking but that being the loudest one?