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Joedoggs · 11-27-2018, 10:57 PM

Greetings,I think by now it’s established that the 871 motor in r.v. Application suffered a high incidence of valve problems...and the original head part #4331387 was replaced with part#5413784 which used a more”robust”valve material,among other improvements to design.the final modification to the head was September 2016 when the new valve seat was introduced.......several people including myself have had rebuilds done after August 6,2014,but before September 2016......in each case I am familiar with, the head replacement had the design improvements,valve material improvements but....did not have the valve seat because it had not been introduced yet...HERE IS THE QUESTION:have any of you(other than mr d)experienced a subsequent failure of valve/head/turbo on a rebuild completed after September 10,2014??? To be clear,with the cm871 isx originally rebuilt AFTER sept 10,2014.....any failures you have experienced first hand?? Or how much time/miles have you gone problem free after rebuild...Not looking for responses that are second or third hand from some truckers forum where somebody thought they heard something.....thanks much

08Navigator · 11-28-2018, 04:11 AM

What design improvements?

Joedoggs · 12-01-2018, 02:55 PM

Quote:

Originally Posted by 2009 sig

Greetings,I think by now it’s established that the 871 motor in r.v. Application suffered a high incidence of valve problems...and the original head part #4331387 was replaced with part#5413784 which used a more”robust”valve material,among other improvements to design.the final modification to the head was September 2016 when the new valve seat was introduced.......several people including myself have had rebuilds done after August 6,2014,but before September 2016......in each case I am familiar with, the head replacement had the design improvements,valve material improvements but....did not have the valve seat because it had not been introduced yet...HERE IS THE QUESTION:have any of you(other than mr d)experienced a subsequent failure of valve/head/turbo on a rebuild completed after September 10,2014??? To be clear,with the cm871 isx originally rebuilt AFTER sept 10,2014.....any failures you have experienced first hand?? Or how much time/miles have you gone problem free after rebuild...Not looking for responses that are second or third hand from some truckers forum where somebody thought they heard something.....thanks much

ANYBODY???? So far We Have not heard of any failures on isx rebuilt after sept 2014......if you have first hand knowledge of any valve/head/turbo failures on rebuilds after that date please let us know......thanks much

Mr_D · 12-02-2018, 09:04 AM

FYI:
The first rebuild was in Oct 12 2010, they used head 4962732.
The second was in March 2015 using the 4331387 head according to the invoices.

vito.a · 12-02-2018, 10:13 PM

My understanding is the new valves are Inconel steel. This is a super alloy steel designed to resist the acidic corrosion from the EGR system. When they specified the Inconel valves, they probably should have also specified the new Stellite seats to prevent the Inconel valve face from pounding the seats.

What you have is a steel alloy incompatibility issue. The question for you is how long will it take for the Inconel valves to pound the original seats so much they are no longer sealing the cylinder?
Hopefully, it's at least one or two hundred thousand miles. But remember, they are attempting to design to a one million mile life span.

You can discuss this with a metallurgical engineer, but I don't think you have an immediate concern.
Hope this helps.

Mr_D · 12-02-2018, 10:18 PM

My problem is that I can't verify what valves were used in my second rebuild. Nothing I fan find gives me a description nor part numbers of the valves used.

Joedoggs · 12-04-2018, 11:50 AM

Quote:

Originally Posted by Mr_D

My problem is that I can't verify what valves were used in my second rebuild. Nothing I fan find gives me a description nor part numbers of the valves used.

Agree Vito,our research shows exactly that...of the 14 cm871 verified as failed with the #6 intake valve problem,we have found ZERO rebuilt with the more robust valves introduced August 6,2014 that have failed.....MR D since your engine was rebuilt in 2015 using WORN ROCKERS you might ask some of the people on this forum what effect your rebuild using “WORN ROCKERS”would have on the life expectancy of that engine.Some people might say knowing the shop used worn rockers is cause for taking some preventative steps to head off a catastrophic failure.....I know that if I saw where a mechanic requested new parts in the course of a rebuild but that request was”DENIED”and my engine was reassembled with worn parts I would be looking for answers....that could end up costing a small fortune if it causes a catastrophic engine failure.....happy travels...jb

CountryB · 12-06-2018, 06:18 AM

Are the rockers "Worn out" or just "Worn". The term "Worn" and "Worn Out" are not the same.
I doubt any reputable shop would install worn out parts in a rebuild. But here is nothing wrong with reusing parts that are within the wear tolerances of that part.

Joedoggs · 12-07-2018, 10:13 PM

Quote:

Originally Posted by CountryB

Are the rockers "Worn out" or just "Worn". The term "Worn" and "Worn Out" are not the same.

I doubt any reputable shop would install worn out parts in a rebuild. But here is nothing wrong with reusing parts that are within the wear tolerances of that part.

[QUOTE=Mr_D;4306330]As I've posted before mine has dropped a valve twice now, first one was for the original owner at 19,082 miles and it was also an intake valve.

Mine was at 45,154 and also was the intake valve. Now have about 50,500 and it runs strong.

I did find a note in the bill that a mechanic requested that the rockers be replaced due to excessive wear, the request was DENIED. So, it appears that I have out of spec (worn) rockers!!

Joedoggs · 12-07-2018, 10:51 PM

Hello folks,I too think it’s a bit strange that rockers that are worn and out of spec would be used in a rebuild(I think maybe I would have addressed that long ago actually),and common sense tells me that could be problematic.this forum has so many knowledgeable members....perhaps some of the knowledgeable engine guys can weigh in....how about it Vito,navigator,duster???if the history is that an engine has dropped valves twice,eaten 3 turbos,and ruined two diesel particulate filters.....is that indicative of a lemon?? Could it be if the fluids and filters were not changed on time it caused damage??If worn or out of spec parts are used in the rebuild,what happens?? I do know that if my supercharged amg Mercedes isn’t serviced as per manufacturer recommendations,I.e. oil and filters changed,you can count on problems from it,and the warranty is void.....I suspect a turbo on an isx is much the same...dirty oil,they blow up......Cummins acknowledged they had issues with the original valves,and came up with the fix released August 6,2014.....to date we have found zero failures of the new valve.......to me it’s clearly disingenuous for anybody to bash Cummins when......questionable maintenance history,worn parts used in the rebuild,and with 3 turbos,and 2 dpf’s who knows what else was messed up along the way......these forums are a great way to exchange info,one big family of happy campers...however,when only select facts are presented over and over and a smear campaign is conducted,that is not good for anybody....I look forward to hearing opinions about these matters.....happy travels!!!

Airstreamer6 · 12-10-2018, 09:59 AM

Quote "....to me it’s clearly disingenuous for anybody to bash Cummins when......questionable maintenance history,worn parts used in the rebuild,and with 3 turbos,and 2 dpf’s who knows what else was messed up along the way......these forums are a great way to exchange info,one big family of happy campers...however,when only select facts are presented over and over and a smear campaign is conducted,that is not good for anybody....I look forward to hearing opinions about these matters.....happy travels!!!"

I'm not sure what the point here is, but I will say this: I would not consider it as "bashing" or "smearing" if a company is criticized because it:

-produced a faulty and inadequate valve for their engine

-refused to recall them to fix the problem before their customers suffered on-road failures which are not only extremely inconvenient but downright dangerous

-refused to fully compensate customers to fix their problem after catastrophic engine failures

-cannot or will not identify the valves used to repair one of their failed engines despite the fact that the customer is now in fear that the old, faulty-design parts were used again instead of the new valve design.

And now the customer is seeing early signs of another potential failure, like the first two.

Pointing out these facts is not bashing or smearing. It's reporting.

Joedoggs · 12-13-2018, 10:51 PM

Quote:

Originally Posted by 2009 sig

ANYBODY???? So far We Have not heard of any failures on isx rebuilt after sept 2014......if you have first hand knowledge of any valve/head/turbo failures on rebuilds after that date please let us know......thanks much

Once again,anybody have or know of any failures on isx head rebuilt using the new valve released August 2014.....Please let us know....thanks much