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Topic: ISX engines (Read 2249 times) previous topic - next topic

ISX engines

If you know of anyone who has had to have their ISX engine repaired due to the pistons going down need to report it to class action.org and NTSHA. This doesn't need to be only Foretravels, it can be any other RV with ISX engine problems. Thanks.
Lynn and Linda Day and Harry the pug
RIP: Tank 01-2008 to 03-2020
2012 Nimbus 42' build 6555
ISX12-500hp
2015 Jeep Grand Cherokee
MC# 17723

Re: ISX engines

Reply #1
Keeping the RPMs up on grades keeps the EGTs down. Fast idle for at least 5 minutes to avoid heat sink in the turbo keeps the turbo seals in good shape. How do the two go together? High EGTs go quickly out of sight with a bad turbo seal and can burn a hole in pistons in a hurry. The first piston go sends little pieces to it's next door brother also finishing that piston and perhaps the head too.

Increasing the HP always means higher temperature because of more fuel injected. This raises the EGTs. Keeping the exhaust valves set to their proper clearance means they have time to sit on their seats and transfer heat to the head. If they can't, they run hot. If they run hot, they can fail and there goes $30K in engine damage.

Quite a few ISX problems on other forums. In my opinion, it's lack of operator training in most cases. Too many drive big diesels like their car.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: ISX engines

Reply #2
I've had 4 isx engines with a million miles put on each pulling 80k lbs. That doesn't help the people that have issues. The reason I will buy no more is the cost of parts to rebuild and other parts outside of engine such as 3500.00 turbo. 2009 is the newest I have and these are probably newer ones giving trouble for the bus people. I just hope these last 100,000 more miles before Inframe then they will be traded for Detroit's. The are a very expensive engine to work on and I have been very lucky with them. I have bought 1 head and 1 turbo so far. With the miles I mentioned you may ask why kicking them.ive been lucky and don't typically rely on luck.
Dub McBride 1996 270

Re: ISX engines

Reply #3
It appears to hit the 500& 600 series, which I think were manufactured around 2010 onward.Yes, they are expensive repairs, $ 30,000 & up. I have an acquaintance that has had his engine go down twice. Lot of money to cummins or who does the work. That is why the request.
Lynn and Linda Day and Harry the pug
RIP: Tank 01-2008 to 03-2020
2012 Nimbus 42' build 6555
ISX12-500hp
2015 Jeep Grand Cherokee
MC# 17723

Re: ISX engines

Reply #4
Hopefully owners can get some recovery.. It will likely take a class action you mentioned. Odds are the failed engines had very low miles which makes it sting worse.
Dub McBride 1996 270

Re: ISX engines

Reply #5
EGR?
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: ISX engines

Reply #6
The egr system appears to be connected to the engine failures. Back pressures from clogged particulate filter, one fellow said it starts with the #6 cylinder and works it's way down to the #1. That is what happened with our engine. I know that two sensors were replaced in spring of 2017 by Cummins and when the engine yellow light came on in Sept, Cummins in OKC said that was one of 5 possible problems, but to keep heading home as long as the light stayed yellow. We were able to limp it into Nac, since our front was missing the Gen cover and we needed alot of front end work from the deer smack. I saw the destruction of the Piston valves and cylinder sleeves . Neither my husband or I drive the rig like a car. Folks I have communicated with have had low miles with the engine starting to go down about the 25-30 thousand .
If you run into someone who mentions this problem, be kind enough to let them know to contact the class action.org . If enough people report, then we stand a chance .
Lynn and Linda Day and Harry the pug
RIP: Tank 01-2008 to 03-2020
2012 Nimbus 42' build 6555
ISX12-500hp
2015 Jeep Grand Cherokee
MC# 17723

Re: ISX engines

Reply #7
The egr system appears to be connected to the engine failures. Back pressures from clogged particulate filter, one fellow said it starts with the #6 cylinder and works it's way down to the #1. That is what happened with our engine. I know that two sensors were replaced in spring of 2017 by Cummins and when the engine yellow light came on in Sept, Cummins in OKC said that was one of 5 possible problems, but to keep heading home as long as the light stayed yellow. We were able to limp it into Nac, since our front was missing the Gen cover and we needed alot of front end work from the deer smack. I saw the destruction of the Piston valves and cylinder sleeves . Neither my husband or I drive the rig like a car. Folks I have communicated with have had low miles with the engine starting to go down about the 25-30 thousand .
If you run into someone who mentions this problem, be kind enough to let them know to contact the class action.org . If enough people report, then we stand a chance .

Are  you still coach-less? Hoping you are back on the road....
1993 U300 40ft GV SE
Build # 4344

Re: ISX engines

Reply #8
                 I have the ISX-650 , and so far no issues . I run that thing like I am trying to get there on time .On interstates I run the speed limit and usually 5 or so over but not over 75 MPH . And that is because that is what the tires allow and be safe .  On hills or in the mountains on a climb , I maintain the temperature not to go over 212 degrees , but make it work .  On the 2006 Phenix I had ,  came with a M-11 , 500 HP . It had EGR failure at 35,000 miles , $1,400.00 . Always felt that was not enough engine for the weight of that coach . The 650 moves this much heavier coach better . Hope luck does not enter into to equation , but so far --ok and pleased . The Cummins Atlantic service manager in 2011 told me to not slow idle or sight see slowly around town . He stated with a cold start up , when air and  oil pressure is up to drive off at moderate speed till temperature is up to normal operating range , but said do not idle a cold engine . I have seven diesels and do this with all except the two gen sets that run by computer . Kind of amazes me at how tuff diesels  engines really are .  ???  Brad Metzger
Brad Metzger
2010 Phenix 45'

Re: ISX engines

Reply #9
As I posted a while back, a cousin of the shop owner was visiting from Albuquerque for a few days. He was a diesel mechanic in a big shop. He stated that with Cummins, it's usually #6 that fails. Another forum member that I met in Q back in '14 said his also lost #6 and he installed an exchange engine. I almost purchased a medium sized flat bed truck with a Cummins. It lost a turbo seal and quickly burned a hole in #6 with damage to #5. The head was off but it looked to me that the head only had a few marks on it and with a set of pistons, it could be back on the road. In-frame kits are pretty inexpensive compared to shop work.

The only thing I can think of that would make #6 a favorite for failures is less than adequate coolant circulation in the head or block. Perhaps not a problem until the EGRs are high for an extended period and only in certain engines.

A couple of sites with engine failures: 2 blown Cummins 450 ISX motors in 2 weeks... [Archive] - Competition...

Probably a good place to make contacts in action against Cummins: Cummins ISX 650 - iRV2 Forums

ISX valve failures - Engines - FMCA RV Forums – A Community of RVers

Bet this does not happen to the Cummins N-14 engines.

Watch video below but fast forward through all the commercials.

Pierce

https://www.youtube.com/watch?v=3CtAOigx_s4


Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: ISX engines

Reply #10
I was at cummins when a FT came in for generator work. He lost his engine on the motorcade to Nova Scotia and had to be towed breaking his generator.  They had to replace his engine. I don't remember the year but it was about 5 years ago now.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: ISX engines

Reply #11
I think brads driving is why he has had no issues with his 650.

Almost invariably luxury  vehicle  products are babied.

Bought a ten year old 50k Miles Lexus ls460 and it surged while accelerating. 


Service records showed injectors cleaning done recently.

Aha

Service manager  at dealer said they get lots of this.

Cleaner then have the tech road test it and blast it hard.

Switched to top tier gas and changed plugs and drive it aggressively. 

Idles smooth as silk.

Our m11 lacked power.  Various reasons..

Drove it hard like a manual trans  intercity truck for 15k miles.

Noticeable improvement.

Then went through the tune and other mods.

Every used motorhome  I have ever driven was not run hard enough to break it in. 

 No problem for me.,..
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: ISX engines

Reply #12
Think the bottom line here is it's not Pugmonm's fault that they did or did not drive the coach the "optimum" way,you would think
the newer ones would have less problems then the old ones.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: ISX engines

Reply #13
There are a number of RV folks with ISX issues out there, not just single cam but also dual cam. 

http://www.engineprofessional.com/TB/TB040318-2.pdf

Cummins ISX broken valve in #6 - iRV2 Forums


We won't touch a coach with an ISX.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: ISX engines

Reply #14
98548 miles on my ISX 600 and rolling fine. It is a 2006 engine though. Not sure lumping "all" ISX engines as being bad is correct. Diesel engines in RVs seem to be more problematic, just reading this forum is evidence of that. These heavy duty engines are built to run not sit for months. An ISX in an RV is light duty service. Mine went over Monarch Pass with ease and usually is only 30% loaded on most highways. Moves my 46K lbs along nicely and can stay with the cars accelerating through on ramps.  Run em'!!
Previous coach - 2007 Phenix 45'

Re: ISX engines

Reply #15
Has some reliability been compromised for power? Huh this isn't news to most even with $$$-$$,$$$$3 technology. Nothing is free, question is do you spend $$$$ to fix a $$ issue and throw into the dumpster. No political parties named.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: ISX engines

Reply #16
I think that what was a simple call to have those individuals who have had trouble with their ISX engines has degraded onto a free for all on who is or isn't correctly driving their rigs. That was not the intention of the original post. It was simply asking all of you to do one simple thing. That was to pass on to RV folks that they can contact CLASS ACTION. Org, if they had trouble. Is that to much to ask?
Lynn and Linda Day and Harry the pug
RIP: Tank 01-2008 to 03-2020
2012 Nimbus 42' build 6555
ISX12-500hp
2015 Jeep Grand Cherokee
MC# 17723

Re: ISX engines

Reply #17
Pug mom just because your request prompted a conversation doesn't mean your intent wasn't met. If anything your cause got more exposure. I can't see where any harm was done. I think we all wish fellow FT owners the best, the same as other coach brands.
Dub McBride 1996 270

Re: ISX engines

Reply #18
I have to apologize for veering off topic when it was really meant to address to ISX failures and the support that Cummins did or didn't give. Please either start a new topic or let us know exactly what went wrong, when it happened and others with the same experience. I've read some of the information on other forums but I think members would like to brought up to date what happened and what to expect from Cummins.

Again, apologies for taking the topic away from the original intent.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: ISX engines

Reply #19
If you search on Pugmom's posts, the saga started almost 2 years ago

Update on progress of our deer smack from late Sept
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: ISX engines

Reply #20
               Got to clarify my last post -- the subject of the advice I got while at Cummins Atlantic  was aimed at my ISX -650 .  Some of what he told me was aimed  at the particulate filter on the exhaust side . I don't like the back pressure  restrictive  flow caused by it , but %$#$% ---have to live with it .  Didn't mean that what I posted was for all Cummins engines .  ???  Brad Metzger  PS-Now have 113,603.6 + miles on it
Brad Metzger
2010 Phenix 45'

Re: ISX engines

Reply #21
Folks, I will bring you up to speed as much as I can. As Michelle noted, this is going on 19 months and We are hoping that the end of the tunnel is almost here. I know that there are some who are not impressed by Bernd, but he has worked his way through each problem that has surfaced . Believe me, it has been a domino effect. We had to replace all 6 cylinders and cylinders sleeves along with having the head gasket re-milled. The erg sensors which had just been replaced by Cummins in spring of 17 were found to have been improperly replaced. But according to Cummins, they could not honor any warranty as the date of placement had passed, which is their right. The particulate filter was found to be totally clogged. It was cleaned and the engine re-clogged it within 2 hours during a road test around Nac. Bernd brought in  a Cummins rep who said to replace the filter with the same kind, but there was no guarantee that it would work for any length of time . Bernd's tenaciousness in researching aftermarket filters has lead to one that performs correctly versus the one recommended by Cummins. The fan that traveled to England and back also had to be re-fitted due to new modifications performed in England. Just when it appeared that we were going to hit the end of this nightmare, an $90.00 fuel pump malfunctioned and had to be replaced. During one of the wonderful rain storms we have experienced this spring and the fact that the engine was being tested once more, it was discovered that the air intake for the air filter would suck in rain. No that may not be a Cummins problem.
ISX engines that I know of from discussion on other forums had the following in common.
 1. All started to malfunction somewhere between 25k&35k miles.
2. Always in the #6 working down to the #1
 3. The erg system appears to be the culprit and some folks went with repair that could lead to fines if caught
4 . One gentleman has had his , ISX go down 3 time, once just prior to his purchase, once about a year or so after purchase and he just had work done again.
If I knew what I know now, we would not have bought this coach. But at the time, there wasn't as much to find out there on the net.
Brad may have lucked out with his engine, as it appears that the ones having trouble were made late 2010 & post 2010.
Lynn and Linda Day and Harry the pug
RIP: Tank 01-2008 to 03-2020
2012 Nimbus 42' build 6555
ISX12-500hp
2015 Jeep Grand Cherokee
MC# 17723

Re: ISX engines

Reply #22
Thanks for bring us all up to speed. I'm sure disappointing is the understatement of the year. I've heard about the Cummins intake valve supplier supplying poor quality valves. Seems #6 is the first to fail but unless you do your own work, the shop is going to charge a fortune. What is the warrantee period on these engines?

Link to the the ISX intake valve problem, PDF: http://www.engineprofessional.com/TB/TB040318-2.pdf

Hope you're back on the road soon and get satisfaction from Cummins!

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: ISX engines

Reply #23
Thanks for bring us all up to speed. I'm sure disappointing is the understatement of the year. I've heard about the Cummins intake valve supplier supplying poor quality valves. Seems #6 is the first to fail but unless you do your own work, the shop is going to charge a fortune. What is the warrantee period on these engines?

Pierce

5 years or 100,000 miles
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: ISX engines

Reply #24
Sounds good on paper,so tell us why are they not fixing the ones that fail at this 25k to 35k miles,sounds like they just give you the
same crappy parts that fail and hope for the best.Apparently they have many ways to slide out of a warrenty claim,hence the class action law suit.It's just me but if I had one that has not failed yet first thing I would do is put in some good synthetic oil and an
extra bypass filter,every little bit helps.
96 U270 BUILD 4810
85 380SL
Drummonds TN.