ISX problems again?

[nothermark]

I wonder how far legal action would go with this. The huge number of trucks and buses with no problem would not look good compared to the low number of motor home chassis. It seems the real problem is folks don't drive enough.

Given todays abundance of cameras to look into tight places I would expect a good shop could tell what was going on. In my mind it would be worth the price to get it done with current parts as Cummins seems to have figured out at least part of the answer. There may not be an answer that complies with EPA requirements they also have to deal with.

[Mr_D]

To check for the chordal erosion requires at least a partial teardown since you can't see the top of the valves with a borescope.
As above, I am really considering doing a preemptive rebuild along with checking the bottom end bearings. I think I'm looking at $20-25,000 and being able to drive it in rather than $35,000 and towing with the interruption of a trip.

Even so I have no way of knowing if the fixes are a permanent solution and it could do it yet again.

[Mr_D]

Originally Posted by Unplanned

Mr. D, have you looked into this?

https://www.m18performance.com/produ...cm870-stg1.htm

Sounds like it might be your answer if you don't put many miles on. I'm pretty sure that there are a lot running around using a delete kit. Might be a bit frowned upon, but who will ever know?

Happy Glamping.

I have a CM871 that kit us for a CM870, but they do have several for mine, and we did have EPA checks here, but I need to check and see if it's still in effect. I know there were some changes in the last year or so. I do have The Ugly Fix, which closes the EGR valve as soon as the engine starts and doesn't throw any codes.

[08Navigator]

I am sure that delete kit works great...but, for the little I know about the ISX...I would never block off the coolant feed from the water pump to the number 6 cylinder ...you are throwing gasoline on the fire! Look at the water pump casting...if you block the egr feed ...look at what's left to feed the block...I doubt very much if the folks that designed those delete kits where engineers or did any dyno testing to temp after the kit was installed. Buyer beware!
If you would be interested in a # 5413782RX cylinder head ,I believe it is the latest and greatest...I would love to make a deal. I will never use it.

[Mr_D]

Won't be doing ANY kind of delete. The Ugly Fix doesn't do anything but close off the gas flow at all elevations rather than just above 7,500 ft elevation like the stock system does.

[bluepill]

Might be worthwhile to contact the law firms involved in the ISB block settlement:

https://topclassactions.com/lawsuit-...ement/#howmuch

[Ivylog]

I wonder if we could get a Cummins Coach Care policy on our 10 year old rigs/engines? Wonder if they would ask which engine we have and adjust the price accordingly.

[Mr_D]

Trying to find out if the carbon scraping liners and matching piston assemblies are required. That adds about $750 per cyl to the cost.

[Unplanned Tourist]

Just talked to the warranty manager at Peterbilt, Kamloops this morning. ISX engines have a problem with a ridge forming in the slave piston bore for the engine brake (Jake) causing the piston to hang up after a longer downhill run.

Here's a couple pics of the broken valve stems....

[Mr_D]

Have not seen or heard of that one. What year, model, hp and mileage is affected?
The chordal failure is happening at low mileage about every 3 years.

[Ivylog]

Originally Posted by Unplanned

Just talked to the warranty manager at Peterbilt, Kamloops this morning. ISX engines have a problem with a ridge forming in the slave piston bore for the engine brake (Jake) causing the piston to hang up after a longer downhill run..

With the valve not getting out of the way soon enough the piston is going to break the valve off eventually. Of all the theories I’ve read for #6 being the one to break, I like this one the best.

On low jake, which pistons are used?

Mr D, do you have a lot of Jake use in your travels? At high rpms?

Marvel Mystery Oil to the rescue?

[Mr_D]

No long grade use on the jake. I've put less than 9,000 miles on the rig in just under 4 years due to the late DW's health and death.

Have you or the manager have a TSB for the bore wear?

[Ivylog]

Originally Posted by Mr_D

To check for the chordal erosion requires at least a partial teardown since you can't see the top of the valves with a borescope.
As above, I am really considering doing a preemptive rebuild along with checking the bottom end bearings. I think I'm looking at $20-25,000 and being able to drive it in rather than $35,000 and towing with the interruption of a trip.

Even so I have no way of knowing if the fixes are a permanent solution and it could do it yet again.

I would drill a hole through the alum intake manifold opposite #6, big enough for a camera to look at the intake valve for erosion instead of pulling the intake off. Could put a pipe plug in the hole for easy future inspections.

[randomledder]

You will have to drill a hole in the cylinder head to get directly opposite #6 intake valves.