IInjector tip cracked off ISX 600P

[Rawze]

(12-10-2020 )Volvo8873 Wrote:  Is it me or did we have another thread started similar to this a few years back?!?

yeah. Apparently that person must have been convinced somewhere that is was normal to have intake valve failures on the isx. Seems they are mis-informed over on those motohome forums or something.

- Some info on this type of intake valve failure was released in 2015 and followed up by a TSB in 2016: ( https://quickserve.cummins.com/qs3/pubsy...=tsb150130 ). Even the TSB says it can be one of many reasons when the engine is operated outside of its normal expected ranges.

It basically says exactly what I said... Severe duty / (i.e. abuse of engine) leads to a premature failure of this type. - It had nothing to do with motorhomes, but severe duty and abuse. - I know I have seen this failure before and it has always been associated with accelerated valve seat wear or simply a lot of age and fatigue on an old engine. ref: http://rawze.com/forums/showthread.php?t...8#pid18718

Or from a deleted/abused/cranked up HP engines if it occurred as early on (at only 48k miles) like that person earlier in the thread had described. so ... NO.. it is not a common thing at all to happen this early so this points directly towards abuse or neglect of some sort if it is happening regularly in a certain type of application.

Needless to say, in a confined space with inadequate cooling, etc... like in a motor-home, this type of failure would be seen more often but it is not the fault of the engine.... but rather its improper application or abuse due to modifications.

That is why I said in the earlier post, what I said... but the person asking the question wanted to be a teenage-burp-tard instead of having a reasonable conversation about it.

- I have been around this type of failure a few times... On a normally operated engine, it can be predicted before it happens by measuring valve sear wear and detent clearances to the jake-brake (mentioned in the bottom section of this old rant post: http://rawze.com/forums/showthread.php?t...66#pid9466 )

- So... If that engine he mentioned only went 48k miles and the valve failed in the same way that TSB mentions .... something caused it ... and in that short of time /operating hours .. It is most likely abuse!.. and the most likely scenario is from a bad delete program due to the fact that just about every that I have person so far that I have met with an ISX motorhome, they want to delete their engine right away and then want to go about turning up the horsepower too. Trouble is that added horsepower in those things easily gets above what the cooling system can handle and the delete programming that most shops do in fact can easily cause engine failures of this type in such an application. That or some other thing someone did to abuse or neglect the engine that proper maintenance and care could have prevented. I suppose someone could blame the mortorhome company for inadequate cooling or CAC cooling, etc... but this is likely a stretch.

This is also why I mentioned aftermarket parts. Who knows how many pre-2016 updated heads, valves, injectors, etc. and knock-offs, usually from china are out there sold as so-called "quality parts". Even so and before that update to the valves, this type of failure was not a regular thing under any normal sort of application.

- Only other thing I can see is perhaps excessive idling at low rpm of the engine for several months at a time of for perhaps accumulated over quite a number of years, ,.. who knows ... causing enough valve seat wear to finally make one crack and let go. - Again... age, neglect, etc. and failure to adjust/check the overhead valves and clearances vs operating hours to catch this type of issue before failure happens.

Those are my thoughts on it any ways. Maybe my followup will help others out there who are trying to get more info on this.