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Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 8679
Experience:  I am ASE Master Truck Certified.
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This question is only for "Cat Man" and I have a questions.

Customer Question

This question is only for "Cat Man"
Hi, my name is ***** ***** I have a questions.
I own kenworth T600 2007 with C15 Acert NXS09144. with 1 035 600 miles on the engine.
I have vibrations on idle 600 rpm. when i start to increase rpm then between 700 - 850 its get better then it starts shaking more all the way up.
4500 miles ago i change harmonic damper and i put there balancer ( both from Pittsburgh power) and new in head wiring.
After that it was riding better. less vibrations but then at 4300 miles i started hearing noise and vibrations. its humming in deep bass (like subwoofer in some cars)
when the engine is under power. The truck doesn't loose power no smoke at all. Today I went to cat dealership. at first they said they feel the vibrations. then they ran cylinder cutout test, intake valve actuator test and intake valve actuator solenoid test. All test pass with ok result. ( a can send you a copy of the test result ). I have there 84 inactive codes, all for intake valve actuator #5. I let them change the VVA (5 and 6) have them perform valve adjusting. then they performed all tests again and pass ok. But the vibrations is still there. they said they have no idea why.
Can you help me please ?
Submitted: 10 months ago.
Category: Medium and Heavy Trucks
Expert:  Cat Man replied 10 months ago.
Thanks for asking your question. I will try and help you out.
Normally vibrations like this are caused by either a bad Iva housing or injector. When it's not. I often find the vibration coming from one of the cylinders. It could be wrist pin wear, ring and liner wear or damaged piston. With over a million miles and it passes Iva and cylinder test. Plus it has a new vibration dampner. I must suspect the vibration is coming from one of the cylinders.
Please reply back if you need more help or have more questions. I am happy to assist.
Customer: replied 10 months ago.
Hi,
thank you for your answer.
I don't think neither of the options are the case. in the service yesterday, they also open the oil filter to find out if there is anything trapped. It was clean. If it was wrist pin ti would make metal knocking, clicking sound. Witch it doesn't.
Every time I have the oil changed, I have the oil analyzed, and everything is in normal. There are no metal in oil pan at all.
Any other suggestion.
Expert:  Cat Man replied 10 months ago.
Thanks for the information. I agree. You should see something in the oil sample but I have seen many cylinder problems and nothing has shown up on an oil sample.
Plus if it's not the injectors, Iva, or dampner. The cylinders are all that's left that I have seen cause a vibration. I am sorry. I wish I had better news.
Customer: replied 10 months ago.
Have you ever seen a new harmonic dumper has being defective and stop working after 5000 miles?
when the engine is cold the vibrations is not bad but after few hours of driving, when the engine gets hot the vibrations is much worse.
Expert:  Cat Man replied 10 months ago.
No I have not ever seen a new bad dampner. Sorry. It's rare that dampeners ever fail to be honest.
Expert:  Cat Man replied 9 months ago.
Hey. I just wanted to see how things were going. Please let me know if you need more help. I am happy to assist. If my information was helpful, please leave a good or higher rating so that I receive credit. Thanks.
Expert:  Cat Man replied 9 months ago.

Hey. I just wanted to see how things were going. Please let me know if you need more help. I am happy to assist. If my information was helpful, please leave a good or higher rating so that I receive credit. Thanks.

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