Dropped Valve ISX650 Cummins

[garyreed]

Harold I am very sad to hear about the EGR issue, Sounds like it was a few days out of warranty., Will they help any with the cost?

Gary

[hwarkentin]

Talked with Mike at Cummins about Warranty and we've agreed to use the same approach we did with the dropped valve. Pay for the repair and appeal to Cummins for the best possible reimbursement. Worked well for the engine, we hope for the best with the EGR.

[garyreed]

Sounds Like Cummins may be trying to make things right.

This series of engine was touted as the golden child.Designed to put Cummins back on top of the horse power and dependability pedestal that it was knocked from in the mid 80's. It has never quite made it with this engine. The smaller B, C, L, M and the electronic versions of these held there own.

Did it have clean maintainance records when you bought it?

Gary

[jleamont]

From experience, the engines between 2007-2011 were more prone to problems, just like this with most if not all USA engine manufactures. The regulations came so fast they were all scrambling to make it work for survival and the economy was crashing around them in the process they all were working with tight budgets to make the required emissions work to survive. Not to make excuses for them but the industry was a mess at the time. I cant count how many EGR coolers I have replaced since their introduction in 2003-2004, then they got worse when the particulate filter technology came along. I was so frustrated as a Technician I bailed out of the dealership side and went into fleet management to get away from it.

Hopefully it works out for you. Cummins is a good company I would be surprised if they left you hanging.

[garyreed]

I fully agree with you Joe.

Those were very tough years for all makers of engines, even the smaller ones ie. Volkswagon.

Gary

[obedb]

Joe,

You would probably know this. Was the 650 ISX offered to the trucking industry at large? I did some research awhile back and don't think it was, but wouldn't bet $$ on it.

If it was not offered to truckers, but is offered to RV builders does that pass the smell test? If I could afford to really trade up (and I can't) I would be really picky about power.

[jleamont]

ObedB, yes it was and it had the same concerns listed in this post. There were not many of them since the heavy truck OEM's began to heavily produce and push their own engines to increase their profit margins, in those years the Cummins was an option that was expensive and still is an option that has become more reasonable in pricing. Now they push their engines claiming fuel savings when all of the driveline is working with each other not against each other. I know I am sold on one OEM, when I have a problem I have one phone call to make, not put all of them in a room and watch them argue over who's fault it is.

In the Medium Duty market Cummins dominated the competition as the dependable engine, fuel efficient option. Even when a chassis manufacture offered their own most still went the Cummins route if it was an option and for some only Cummins was the option, which dictated their sales numbers. One OEM didn't offer it and that almost bankrupted them due to their product reliability when it tanked with the new emission engine lineup. The ISX was not an option in those medium duty chassis, they were ISB, ISC and depending on GVWR, ISL.

I am sure you remember the days when the tractor didn't matter much it was the engine under the hood that did. As the years passed that has changed, now most only want everything from one OEM, especially now that manual transmissions are becoming a thing of the past, everyone wants automated manual transmissions to control repair, safety and fuel costs. We wont purchase any manual transmissions unless its for a special application and that's the only transmission option. From experience it makes it much easier for me when we have a problem all of the finger pointing has gone away from who's component caused the failure to "how are you going to fix this for us"?

[manholt]

Joe.

Did Cummins redo the 600 ISX to a 650 ISX, based upon wanting to compete with the Volvo 725? If not then why rebore a dependable 600?

Carl

[jleamont]

Carl, not sure other than there is and probably will always be a Horsepower war between manufactures, they don't want to be left behind.

[wildebill308]

I have to ask How can idling cause a dropped valve? I am not sure I understand exactly what is happening.

Is the valve failing as in the head coming off the stem or is it the keepers not holding the valve?

I would expect failure at max rpm where max loading is applied.

Bill

[obedb]

When I idled as a trucker I always set the rpm at 1000 or thereabouts. That brought the oil pressure up to normal. Perhaps low oil pressure at 500 or so could set things up for failure later in the engine's life? I always had a fan switch and I turned it on when using a'c. Didn't like the constant cycling of the fan. Compressors were subjected to high pressure and it was tough on both the belt and the clutch. Worked for me for many years. As to the high powered RVs that seem to be at least a little more subject to valve failure, I wonder why would anyone want to run a 50,000 lb RV (seems to be the norm on the high end rigs) up a steep grade at highway speeds? If you are blowing by slower moving traffic, the danger of an accident increases. 500 hp and increased torque offered by a bigger block would be fine when guiding one of those big boys. IMHO

[garyreed]

When I idled as a trucker I always set the rpm at 1000 or thereabouts. That brought the oil pressure up to normal. Perhaps low oil pressure at 500 or so could set things up for failure later in the engine's life? I always had a fan switch and I turned it on when using a'c. Didn't like the constant cycling of the fan. Compressors were subjected to high pressure and it was tough on both the belt and the clutch. Worked for me for many years. As to the high powered RVs that seem to be at least a little more subject to valve failure, I wonder why would anyone want to run a 50,000 lb RV (seems to be the norm on the high end rigs) up a steep grade at highway speeds? If you are blowing by slower moving traffic, the danger of an accident increases. 500 hp and increased torque offered by a bigger block would be fine when guiding one of those big boys. IMHO

When did you start driving? Sounds like you may have cut your teeth on a small cam Cummins or a 71 series Detroit.

Gary

[manholt]

What I don't understand is why would you need or want a 600 or 650 in a glorified camper to begin with!? Per the Cummins rep that came by So. Plains Cummins, where I currently am camped, the 650 is the cats meow now, and the problems they had is behind them. OK, makes me wonder why Cummins has a downturn in sales and have laid off 2,000 workers?!

There are 16 coaches here waiting for service, new to 3 years old from DeMontrond RV in Houston, 43' to 45' and 450 to 525 HP. No 650!

Carl

[garyreed]

Carl

Those Cummins rep's are only paid to spin the good stuff, especially if they are out in the yard talking to customers. If you want the truth, talk to the guys doing the work and make sure they are alone and you might get the real facts. I am sure there are some good 650 engines and happy customers out there. The guys I know with those are not.

Gary

[wildebill308]

What I don't understand is why would you need or want a 600 or 650 in a glorified camper to begin with!? Per the Cummins rep that came by So. Plains Cummins, where I currently am camped, the 650 is the cats meow now, and the problems they had is behind them. OK, makes me wonder why Cummins has a downturn in sales and have laid off 2,000 workers?!

There are 16 coaches here waiting for service, new to 3 years old from DeMontrond RV in Houston, 43' to 45' and 450 to 525 HP. No 650!

Carl

Just might have something to do with the slump in oil prices.

Bill

[obedb]

Motorhomes are not sports cars. Especially the really high end ones that come at or near 50k with a toad. There are some really "large cars" out there in trucking (that is what we truckers call the 600hp and up rides). They usually hit the overhaul shop before the less powerful rides do but they were almost frighteningly fast and powerful in trucks. Imagine one in an RV! As I have already said, I would not go for anything in an RV over a 500 hp 12.7 liter Series 60 or a 475 hp C-15 Cat (if available in an RV?) but alas, I doubt that I will ever be able to afford either. The C-15 in an 18 wheeler was just amazing. Too bad they got out of the over the road business.

[jleamont]

My previous post on this thread somewhat explains why an engine only manufacture is being pinched off. I took my CDL test in a International, Cummins powered with a compression release. it was only 300hp and would pull you into the seat. ObedB and Gary are probably laughing now. After driving todays road tractors with the higher HP engines, they really don't out perform the old ones, they just ride and handle much nicer.

Almost everyone is now looking for a road tractor with the power train built by the same company as the hood ornament, just like a car or light duty pick up truck. That in itself would make sense for Cummins to cut back as their demand is dropping off.

CAT bailed when they just couldn't get the new technology right and its reliability fell apart in the 2007-2008 engines with a DPF. My previous employer had 52 of them and when I left they and cat were paying the local Cummins dealer to pull and replace them with Cummins Power to a sum of $38,000 per truck. Per truck we were averaging $7200.00 per year in towing expenses and $44,000 per year in repairs. We had CAT out for meetings, the local dealer trying to fix them, but in the end they agreed it was an engineering disaster and nothing could be done. So they were picking up part of the tab for the engine change. Just typing this I am getting heart burn that was a bad experience then and I hope I never have that mess again.

[obedb]

The twin turbo engines Cat built to try to conform to EPA regs were a disaster. There are places in south central PA that specialize in turning those engines into the original variety. Might get into trouble in California with them, but the Original C-15 was amazing. Nothing pulled a heavy load like one of them. If they were used in DPs, my guess is that those owners are quite happy.

[garyreed]

Joe

I'm only laughing if you're laughing.

Thanks for the insight on the newer model engines. I sold my shop and retired from the repair business in late 2008 so I may have missed the worst of the emissions. Now I help other local guys troubleshoot and try keep them from replace parts willy nilly.

In 1999, one of my fleet contracts involved mostly 550 and 600 Cats and 500 Detroits with one 650+ ISX. It was a test unit and factory set to out perform the 600 Cats. I had a checklist that filled a 3inch binder of what to inspect every time the unit came in the shop. Cummins also had an agreement with the fleet owner to bring the truck into Rocky Mountian Cummins when in Denver for them to inspect. That fleet averaged about 150,000 miles per unit per year and there lease rotated around the two year mark. The ISX probably had around 80,000 in two years and seemed like twice that backwards behind a wrecker.

With that said, when it ran, it was amazing, and would run 7+mpg and the rest of the time would limp from Cummins shop to Cummins shop. Now to add a good spin, one of my owner operator customers in 2001 bought a new ISX 450 and was only in the shop to change the oil at 35,000 intervals. So if Harold continues to have trouble, he might ask about derating, yes I did say maybe lower the horse power. Hopefully now though they will have it fixed.

Now, as far as the laughing, I have a 1947 Kenworth with an NT 180 naturally aspirated with a 4x3 married transmission and camel back spicer rear ends and yes it does have a compression release and jake brakes. Not to purttie but is a blast to drive around the yard.

Gary

[manholt]

I learn a lot, just by reading about your trucking experiences. Thanks for that!

I still can't wrap my mind around running a 600+ in a cookie cutter DP. The newer AC Tradition (mine) has a 500 standard and 600 option, at 51K pounds, that is ridiculous. I can understand a 600 in a Newell or Liberty coach as they are around 25K heavier than me...however, I wonder how much of that extra weight is because of beefed up chassis and big engine?

Carl

[kento]

Gentlemen,

I have been reading about blown engines on the Cummins ISX 650 and my question is this:

I am about ready to purchase a 2007 Country Coach from Premier RV in Junction City and it has the Cummins ISX 600 hp engine. Has anyone had any problems with the older 600 hp model Cummins engines.

You all have me concerned at this point.

Thanks,

Kent

[wolfe10]

Kent,

Welcome to the FMCA Forum.

My concern is that there will not be enough ISX 600 HP's in RV's on the road for you to get relevant feedback.

Have you visited with a Service Manager at a large Cummins dealership-- probably a good source of info if you can get him to open up about the issues?

[jleamont]

Kent just to add to Brett's comment, I would take the engine serial number along and ask an authorized Cummins service center if that engine is affected by the concerns listed on this post. If memory serves me right it was only a production line of them that had concerns, not all of them. Not to mention maybe this is one of those but had all of the updates performed by the previous owner or under warranty...who knows, but worth a phone call to them especially if you like the coach.

[rpelatt]

Gentlemen,

I have been reading about blown engines on the Cummins ISX 650 and my question is this:

I am about ready to purchase a 2007 Country Coach from Premier RV in Junction City and it has the Cummins ISX 600 hp engine. Has anyone had any problems with the older 600 hp model Cummins engines.

You all have me concerned at this point.

Thanks,

Kent

Our 2009 HR Navigator has the ISX650. There has been a lot of discussion of this engine on the IRV2 site. It seems this engine first came out around 2005 and ran up to 2010 in this form. Ours has 27K miles and is a total pleasure to drive. The power is nothing short of awesome. However, I do not push it too hard; I back off if the temp starts to rise while pulling long grades. For those that do suck a valve the cost seems to run $22K and up to $28K if it takes out the turbo. It appears that Cummins will pay around 50% of the repair cost. I stopped by our local Cummins shop a few months ago to pick up a spare fuel filter, and asked if they had any info as in bulletins regarding this engine and got a very emphatic "No". It would appear they still do not want to publicly acknowledge this ongoing problem.

Also de-rating the engine to a safer HP does not appear to have any real bearing as to longevity, as the problem is really in the design of the head.This is just one of those designs that were not fully field tested before production started as all engine builders were under the gun to reduce emissions by a certain date. This was in the era where Cat just simply walked away from the on-highway engine market.

We did buy an exclusionary warranty policy for our coach shortly after purchase so later when we started hearing of this problem we were comforted in thinking that if we experience a major failure that most if not all the cost will be covered by insurance.

Good Luck in your decision...Bob

On edit: Don't know what happened but I have posted several times on this thread alone as bpelatt (see post 18 & 23) Now my name got changed ?????

[manholt]

Send a PM to Brett and let him know, it will be restored to correct name.

Carl