Unique DEF Head Failure...but potentially SERIOUS!

[Guernsey]

Would a preventative placement of a welding blanket between DEF tank, batteries and exhaust bellows prevent the damage caused when the exhaust bellows fail?
It would certainly not prevent the exhaust bellows failure, but might prevent the damage to DEF tank and other components? Being able to drive to a repair facility without a derate or causing additional damage would be a real plus….

[02trader]

Dr. Mike
I can't speak for how other extended warranty contracts may work but mine (Compass/AGWS) specifically excludes most exhaust issues. I just completed the replacement of the exhaust bellows system and DEF head in my 2016 Anthem at a Cummins shop in Denver and it sounds like Compass is going to cover the cost and labor for the DEF head but nothing related to the exhaust issue.

[jestal]

Originally Posted by Dr. Mike

Quick questions: Would an extended warranty cover this?
Our coach has had previous owners. Question: How do I know if this part has been replaced?



Be safe

Dr. Mike

I have no idea about an extended warranty coverage. You would have to run it by the specific warranty company. I'm not a warranty expert but I would think an extended warranty might cover it but since I chose to "self insure" I obviously picked up the tab. I find where the extended warranties often disappoint is that they might fix the bellows section but would not cover collateral damage which was most extensive and expensive. One reason I do not usually have a repair warranty.


I would inspect the part thru the hatch in the rear of the coach. It is actually right beneath your feet so to speak but what you see is a metal heat shield hiding the bellows inside/beneath. Looking thru the hatch you can see the ends of the connector at each end on either side of the engine. You can look in at the bellows from the ends with a mirror or borescope like device.

You can also see the exhaust from the DEF bay. with a strong light the exhaust is visible and you can at least see if part of the crossover is hanging down which would indicate it has failed. This is not fool proof as it may be cracked but not really separated yet like my buddy with the Tiffin/Spartan

My coach had an exhaust connector across the engine that was 100% bellows or convolutes for its full length. If that is what you see then it should be replaced as preventive maintenance. INHO I cannot imagine anyone would have replaced that part with another one that was 100% bellows

No way to tell if it has been replaced before unless it has the updated part that is half bellows and half straight pipe. Even then that may have been the OEM part on that particular build so you still cannot tell if it has been replaced.

[jestal]

Originally Posted by Guernsey

Would a preventative placement of a welding blanket between DEF tank, batteries and exhaust bellows prevent the damage caused when the exhaust bellows fail?
It would certainly not prevent the exhaust bellows failure, but might prevent the damage to DEF tank and other components? Being able to drive to a repair facility without a derate or causing additional damage would be a real plus….

I would not recommend this as it would block cooling airflow thru the area under normal operation this causing other problems. Much easier to order the heavy duty crossover and just replace it.

[Mikenat]

Originally Posted by Guernsey

Would a preventative placement of a welding blanket between DEF tank, batteries and exhaust bellows prevent the damage caused when the exhaust bellows fail?
It would certainly not prevent the exhaust bellows failure, but might prevent the damage to DEF tank and other components? Being able to drive to a repair facility without a derate or causing additional damage would be a real plus….

I did create a welding blanket riveted to sheet metal double folded and sealed the open space to shield the def system. The exhaust from the engine is around 1200 degrees. I used an infrared device to measure the bellows, muffler end and then the def tank itself after a highway drive. I was shocked at the temperature of the def plastic tank 174 degrees. So it took a little fabrication to seal it but it would definitely prevent the incident in the OP. It also reduces the ambient temperature of the def fluid itself.

[Guernsey]

I am away from my Entegra for the summer and will leave on a long trip when I return in August. I had a friend do a thorough look see of the exhaust bellows area with a face time call. We looked from side and from the inside cover. All looked good.

But I do believe a replacement bellows pipe is a good decision when I have time In the meantime, the welding blanket still seems like a plausible preventative solution. I am also surprised to read Mikenat’s discovery of such high heat on tank as is. It also makes me wonder if the high temperature is degrading the DEF fluid and perhaps causing additional problems with the DEF sensors?

[DiddyPnut]

Sadly the bellows failure is not limited to Spartan. We have a Tiffin Powerglide chassis with the ISL9 450hp and crossover bellows split. While it only softened and distorted the high temp wire loom and melted one 1/4" air line related to air bag dump, we were lucky it happened on our way to the S&B. Tiffin had upgraded their crossover pipes & bellows and replaced it for free. Searching IRV2 I found several threads on this failure. Definitely something I check regularly when doing maintenance.

Also as suggested in this forum, we keep a printed tow check off sheet up front to hopefully limit any coach damage. Thankfully have not needed it.