FCA Mod, now it really rattles???
#1
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FCA Mod, now it really rattles???
I did the FCA mod just a little while ago, but didn't get to the second stage of the DIY CP3 mod.. I put the FCA back in and fired the truck, now it rattles at idle the as loud as it does when it is cold started at 20 degrees (but it is more like 90 right now)?? It really sounds like an older (pre-common rail truck).... The even funnier thing is that it gets quiter when you start to accelerate to pull away...
Is this a common reaction to the mod, or did I remove too much??? I polished the heck out if the little piston, and it slid freely into the cylinder. It drives find, idles well, it does make one "lump" during start up but nothing really noticable to the normal person.
I even pulled out some timing (set the rokk sensor back to stock position), MP-8 to stock, but it really didn't change. I don't mind the added noise, but I don't want it to get any louder (like when winter comes)....
Any thoughts???
Is this a common reaction to the mod, or did I remove too much??? I polished the heck out if the little piston, and it slid freely into the cylinder. It drives find, idles well, it does make one "lump" during start up but nothing really noticable to the normal person.
I even pulled out some timing (set the rokk sensor back to stock position), MP-8 to stock, but it really didn't change. I don't mind the added noise, but I don't want it to get any louder (like when winter comes)....
Any thoughts???
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I modded mine and its fine but my brothers isnt. He just got a some codes and it started to rev. When it revs he said rp is high like 20,000. I told him to check the connection to the FCA and make sure its connected good. Maybe check that Asher
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Could be off, people have had luck by pulling the cp3 and reinstalling with the gear either 30, 60, 90* off of where it was.
It eliminates the timing misshap of the cp3 supplying the injectors
Something along those lines, im sure someone can help explain it better.
It eliminates the timing misshap of the cp3 supplying the injectors
Something along those lines, im sure someone can help explain it better.
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#8
read all about it here.....
https://www.dieseltruckresource.com/...hlight=diy+cp3
https://www.dieseltruckresource.com/...hlight=diy+cp3
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No, not unless he pulled it. It MAY amplify the problem though, just a guess...
If you had some rattle at idle before, and after the FCA mod it could make the problem more noticable...
People have said that pulling/rotating it 30/60/90 has helped reduce/eliminate the rattle they had at idle.(cp3 rattle, not cummins rattle)
If you had some rattle at idle before, and after the FCA mod it could make the problem more noticable...
People have said that pulling/rotating it 30/60/90 has helped reduce/eliminate the rattle they had at idle.(cp3 rattle, not cummins rattle)
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Yah Ive heard of that, there gets to be a little play in the gears. I see what you saying though. I didnt pull the pump only the FCA. By the way is the cp3 tuff to pull and reinstall?
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Ill see if I can dig up the post, I think it was on here....
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Heres the link...
http://www.cumminsforum.com/forum/3r...g-results.html
http://www.cumminsforum.com/forum/3r...g-results.html
I have been having (as many others have) an annoying engine knock. Mine occured only at idle and only after the engine warmed up. I read on another site that there has been success in getting rid of the noise by retiming the cp3. I tried it and I am happy to say it seems to work.
First off there are different causes for an engine knock, mine was a metallic sounding knock from the front left side of the engine. To change the timing is pretty simple. First remove the belt from in front of the access hole on the timing cover in front of the CP3. This will give you access to the nut that locks the timing gear to the CP3. Remove the nut and washer behind it(being carefull not to drop either inside, doing so will require much more work). Next you need a puller, steering wheel puller or small T bar will work to pull the gear loose from the CP3. Depending on how much dexterity you have you may or may not need to remove the upper radiator hose and bracket under it, in order to attach the puller to the gear. The fan is in the way of a standard length pusher bolt so I cut mine off, if you dont want to do that you can remove the fan. With puller installed and pusher bolt in place remove the gear from the cp3. The gear is a taper fit with no key way, so once the gear is loose all you have to do is rotate the engine to retime the cp3 in relation to the engine. I did mine twice before I found the magic spot, but it ended up about 60 degrees from where it was. Once you have rotated the engine re-install the washer and nut and torque to 77ftlbs(I used a ratchet on a dampener bolt to keep the engine from turning). Pictures are available in the service manual and will give you a good idea what is involved. It took me about 30 minutes to perform this procedure and I'm happy with the results.
Why does it work, well it seems that the cp3 being a piston pump behaves just like an engine, it takes force to push the piston on a compression stroke, and then after TDC it tries to spin faster(or easier) until the next compression stroke. When the engine is doing its compression stroke at the same time the CP3 is on its return stroke it can cause the gear teeth driving the cp3 to loosen and then slap back into contact causing noise.
First off there are different causes for an engine knock, mine was a metallic sounding knock from the front left side of the engine. To change the timing is pretty simple. First remove the belt from in front of the access hole on the timing cover in front of the CP3. This will give you access to the nut that locks the timing gear to the CP3. Remove the nut and washer behind it(being carefull not to drop either inside, doing so will require much more work). Next you need a puller, steering wheel puller or small T bar will work to pull the gear loose from the CP3. Depending on how much dexterity you have you may or may not need to remove the upper radiator hose and bracket under it, in order to attach the puller to the gear. The fan is in the way of a standard length pusher bolt so I cut mine off, if you dont want to do that you can remove the fan. With puller installed and pusher bolt in place remove the gear from the cp3. The gear is a taper fit with no key way, so once the gear is loose all you have to do is rotate the engine to retime the cp3 in relation to the engine. I did mine twice before I found the magic spot, but it ended up about 60 degrees from where it was. Once you have rotated the engine re-install the washer and nut and torque to 77ftlbs(I used a ratchet on a dampener bolt to keep the engine from turning). Pictures are available in the service manual and will give you a good idea what is involved. It took me about 30 minutes to perform this procedure and I'm happy with the results.
Why does it work, well it seems that the cp3 being a piston pump behaves just like an engine, it takes force to push the piston on a compression stroke, and then after TDC it tries to spin faster(or easier) until the next compression stroke. When the engine is doing its compression stroke at the same time the CP3 is on its return stroke it can cause the gear teeth driving the cp3 to loosen and then slap back into contact causing noise.
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