2008 Cummins ISX CM871 15L 525HP

[makalu]

Hello, a bit of background on this used motor oil. It sat in a motorhome for over 500 days with maybe moving it a couple times around the lot. The motor had a new EGR valve put in, full DPF clean out due to excessive soot, new turbo, and a new fuel filter as well roughly a year ago. They did not change the sampled oil after the work. It now runs and makes power fine it seems and doesn't make any odd or weird noises. Sampled oil use time is unknown other than it was in there a long time. Motor has 52,000miles

Could this be due to rust building up inside the motor during the extended period of non use? Or is this reflective of the work done on it? Is it soot? I don't know.

 

[treyguy]

have you checked into the chordal valve failure issues with these CM871 engines and what happens when they sit for long periods?

 

[makalu]

have you checked into the chordal valve failure issues with these CM871 engines and what happens when they sit for long periods?

Yes, extensively actually. It seems most issues were on the 600HP and 650HP iterations. There's apparently been a redesign of some parts from Cummins. Even some people in the RV community saying Cummins would help with repair costs as long as they signed a NDA type form. I have no idea if that's true or not but so I've read that numerous different places.

 

[treyguy]

Yes, extensively actually. It seems most issues were on the 600HP and 650HP iterations.

that only seems like rumor thats circulated sites like IRV2. i believe this issues has been far sweeping on all CM871 engines. Cummins paid like 50% of repair costs for numerous tanked engines that had this issue and were forced to sign NDA's to keep their mouths shut about it. the fact that it had a new EGR valve is concerning, with that low of miles on a CM871 that has 100% sat for long extended times would have me looking elsewhere. it would be far better if this thing had 352k miles versus 52k miles. i made this decision recently myself and decided its not worth the $35,000 gamble for an ISX rebuild. you could however replace the head with an aftermarket for piece of mind or prevent a ticking timebomb.

3683986 | Cummins ISX Fully Loaded Dual Cam Cylinder Head, New

Benefits of this Performance Cylinder Head: Brand New & Fully loaded Cummins ISX Dual Overhead Camshaft Cylinder head. Our castings are engineered, designed, and assembled in the U.S.A. They are better than OEM quality containing 5% more nickel content in the casting material. This additional...

atldiesel.com

 

[fantastic]

Change your oil on a regular shorter schedule & keep driving it. Sometimes it's cheaper not to look.

 

[makalu]

that only seems like rumor thats circulated sites like IRV2. i believe this issues has been far sweeping on all CM871 engines. Cummins paid like 50% of repair costs for numerous tanked engines that had this issue and were forced to sign NDA's to keep their mouths shut about it. the fact that it had a new EGR valve is concerning, with that low of miles on a CM871 that has 100% sat for long extended times would have me looking elsewhere. it would be far better if this thing had 352k miles versus 52k miles. i made this decision recently myself and decided its not worth the $35,000 gamble for an ISX rebuild. you could however replace the head with an aftermarket for piece of mind or prevent a ticking timebomb.

3683986 | Cummins ISX Fully Loaded Dual Cam Cylinder Head, New

Benefits of this Performance Cylinder Head: Brand New & Fully loaded Cummins ISX Dual Overhead Camshaft Cylinder head. Our castings are engineered, designed, and assembled in the U.S.A. They are better than OEM quality containing 5% more nickel content in the casting material. This additional...

atldiesel.com

Thanks for a link to that head. Certainly nothing is solidified with things people post on the internet. There are likely 100's of thousands of these motors that are in use. Tough to say just how common it is with anecdotal stories everywhere.

Change your oil on a regular shorter schedule & keep driving it. Sometimes it's cheaper not to look.

Thanks for the response. Is this based on experience with an elevated iron content in an oil analysis?

 

[classic70]

My guess is elevated Iron is from sitting for long periods of time where the oil has drained out of the oil rifle. Essentially a few dry starts would explain the elevated iron.

 

[treyguy]

Thanks for a link to that head. Certainly nothing is solidified with things people post on the internet. There are likely 100's of thousands of these motors that are in use. Tough to say just how common it is with anecdotal stories everywhere.

ya they are certainly great engines used in trucks that get driven hard. Motorhomes unfortunately dont see that kind of duty, they sit and rot. this engine has a particularly bad design for motorhome use where if it sits and rots, acidic condensation drips and pools up on the #5 and #6 intake valves causing them to disintegrate. these problems dont really exist anywhere outside of motor home use on this engine.

 

[makalu]

I just talked with the lab over the phone and they said there's (obviously) only so much info they can pull out of one sample but it was useful all the extra info I gave them about the length of time it's sat unused. They also said some particulates probably made their way in with the work done a year ago. Advice was to drive it a bit and resample. Also during oil change to pour fresh oil in while the drain plug was still out to flush as much out the pan as possible.

 

[fantastic]

Thanks for the response. Is this based on experience with an elevated iron content in an oil analysis?

I have no experience with elevated irons myself. However, It would probably be wise to change the oil & run 3-5k & re-test the oil. The iron could come down & not be so worrisome. If it's still high just keep running it & change the oil accordingly.

 

[makalu]

I have no experience with elevated irons myself. However, It would probably be wise to change the oil & run 3-5k & re-test the oil. The iron could come down & not be so worrisome. If it's still high just keep running it & change the oil accordingly.

Thanks, the oil and oil filter has been changed since the sample was pulled. I'd likely do another sample after 1000 miles to see how things are going.

 

[fantastic]

Thanks, the oil and oil filter has been changed since the sample was pulled. I'd likely do another sample after 1000 miles to see how things are going.

Good Plan