12 Valve 2nd Gen Dodge Cummins 94-98 Discussion of 12 Valve 5.9 Liter Dodge Cummins Diesels with P7100 Injection Pumps

Engine nock at low rpm

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  #11  
Old 06-08-2012, 10:47 PM
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i'm with pap and turbo it sounds to me like you got a piston thats making contact with the cylinder....i'm going to bet its #6 and that you will find the #6 piston cooling nozzle clogged up
 
  #12  
Old 06-13-2012, 05:46 PM
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why would nock go away at high rpm tho
 
  #13  
Old 06-13-2012, 06:37 PM
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it may not be going away just you cant hear it because of everything else making noise
 
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Old 06-14-2012, 01:20 PM
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oh ok. well thats unfortunate. sounds like i dont have much choice but to pull it. but ill just build the motor. if im gunna fix it.. im gunna go big
 
  #15  
Old 06-14-2012, 05:05 PM
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do a compression test that will tell you if that is the case without pulling the engine
 
  #16  
Old 06-15-2012, 12:14 AM
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well heres another thing. my cam doesnt have bearings (correct me if im wrong) so my cam rides on the block. and if it oveled out that hole and at low rpm it rattles and at high rpm it balance itself out and nose goes away. and thus that noise i hear is loud gear noise? does that sound reasonible?
 
  #17  
Old 06-15-2012, 11:31 AM
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why would it not have bearings? and todays engines are clearence often to the .0001 of an inch so a wobbly camshaft absolutly wouldnt jive. like broke in have not jivin. and you could never get the valves adjusted correctly an you say you have? what you discribe would be a caticlismic catastrofy. ive never been that deep in a 6bt but have had a plethera of engines apart. cam bearings dont wear heavy. the only engine ive had apart without bearings was like a 58 VW air cooled. im 99.999 to invinity this isnt your issue.
 
  #18  
Old 06-15-2012, 06:27 PM
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From what I have been told they only have 1 cam bearing.
 
  #19  
Old 06-15-2012, 06:38 PM
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Originally Posted by sweetv8s10
From what I have been told they only have 1 cam bearing.
Correct they only have one at the front. The only time more are used is with a billet cam when the block has to be line bored out larger to fit the cam.

Sent with a Droid RAZR in one hand and 14,000 volts in the other.
 
  #20  
Old 06-17-2012, 04:16 PM
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so one end ride on the block and one towards front rides in a bearing?
 


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