Cummins ISB 340 Engine Overheating Overheat Fan Clutch Thermostat Cooling etc.

[Paladin76063]

Originally Posted by paddler54

Yesterday, I drove over to my local Freightliner service center and scheduled a service appointment. While there I mentioned the Freightliner Service Solution 3737 and got blank stares. One gentleman said he'd look it up but later said he couldn't find it. Anyone have a copy of this bulletin? I'm in need of that warm fuzzy feeling!

If you call the Freightliner hot line in South Carolina, they'll acknowledge the TB. They told me it's for diagnostic use only. I believe that the biggest issue is that at the end of the diagnostic flow chart the only way to fix the clutch is to replace it.

[powderman]

Its really amazing how the price of repairs deepends not on the engine but what its in. I have the 340 HP HO engine in my Ram. The clutch fan costs $200 and we changed it out in the campground in about half an hour. Surely there must be a more cost effective approach to fixing the problem. Am I missing something?

[Britcanuck]

My fan clutch failed at 5 years with 33,307 miles. Below is correspondence between myself and Freightliner.

Dear Sirs.
I own a 2011 Damon Astoria motorhome built on a Freightliner XCR chassis
and
powered by 340hp Cummins ISB engine. I have owned this unit since new
and
have diligently adhered to the servicing requirements during the warranty
period for both the chassis and engine. The vehicle VIN is
4UZAB2DTXACAT2290
and was registered at time of purchase. .
Two weeks ago we left on a trip and less than 8 miles from our starting
point
the engine coolant gauge suddenly rose to the red zone and a audible
warning
sounded. In the few moments it took me to seek a safe place to stop, the
engine had gone into limp mode and shortly thereafter shut down
completely.
After about 15 minutes I restarted the engine and with a recovery tow
truck
that had come to my assistance following me we cautiously drove to a well
established repair facility near my home. The diagnosis was a failed fan
clutch which I had them replace.
Some research on the internet amongst motorhome owners with the same
engine
quickly revealed that this incident is not an uncommon occurrence. There
were
numerous instances of the fan clutch failing in the 20,000 to 40,000 mile
range. The mileage on my vehicle is only 33,307.
I saw reference to Freightliner Service Solution 3737 which the facility
that
repaired my coach were able to look up.
I have also read on RV owner forums that some owners have received
financial
assistance from Freightliner Corp. in some of these instances.

The purpose in me writing to you is two fold. First to express my
disappointment that this incident occurred on such a reputable engine as a

Cummins and less than two months past the expiration of the warranty
period.
Secondly, I would ask if you feel that this large expense that I incurred

(copy attached) would qualify for any kind of refund or compensation from
Freightliner Corp. I look forward from hearing from you.

I heard back the same day.

Thank you for your email. The fan clutch is not part of the engine
but put on by Freightliner. The basic chassis warranty is for 3 years or
50,000 miles, whichever comes first. The basic warranty expired 3-30-14,
over 2 years ago. This is part would have fallen under the chassis
warranty, sorry for your issue , but no consideration is given

Sincerely,
**************
FCCC Representative

[bobguigley]

Something to think about....

While getting a chassis inspection at the Gaffney FCCC service center this past December, I raised the fan clutch issue with one of their techs. We discussed the possibility of replacing the fan clutch with a direct drive fan assembly.

Dave, the tech, told me that there is a local place that can fabricate such a part, but it may take a few days to obtain it.

If my fan clutch fails again I will definitely go that route.

He just told me to call him and he'd get the part and ship it to me.

[Hdwick]

I would like to know are all of the coaches ISB340 Hp I am having a similar overheating issues with a 2010 ISB 350

[lclewis49]

I had to have mine replaced on a 09 isb 350 last year.

[hawgguy]

Originally Posted by Hdwick

I would like to know are all of the coaches ISB340 Hp I am having a similar overheating issues with a 2010 ISB 350

My 2011 ISB had the problem. I think it has more to do with the Horton fan clutch than the specific year or 340/350.

[Hdwick]

My 2010 just did the same thing and luckily the fan did not work because when I got it apart the bracket for fan hub that mounts to the motor was broken/ cracked in half right above where the bolts mount to the motor. We all need to get together and put in a complaint to freightliner because this part is discontinued. I had to buy a new mount and complete complete updated fan assembly. The TSB ONLY WENT TO 2007. I only have 24,000 on the coach

[Slateous]

Feel your pain. Mine was at 22,000. 2010 Tiffin. My fear is will I be doing it again in another 20k. Class action may be appropriate. Horton is the culprit. Freightliner is not going to pressure them. No one that buys a Disel expects to be sitting on the side of the road over this kind of a clear defect.

[Britcanuck]

You no doubt saw my posting on 05-22-2016, 09:04 PM The response from F/L was 'tough'
They consider it a chassis part (3 year warranty) as when they build the chassis and install the Cummins engine they don't know if the RV builder wants side or rear radiator and then they install the appropriate fan at which point it's a chassis part and not an engine part (5 year warranty) Yeah, I know that's a technicality but they call the shots. By all means start a petition or the like and I'll be glad to sign on. In the meantime
Good Luck!
I've had mine fixed at an approved service location for 3 Grand (Canadian) and it seems to be running just fine.

[Starxd]

Letting owners of that chassis know the specific service solution to reference will surely cut a lot of the time, frustration, and billable diagnostic hours for them if they choose to replace one failure prone clutch with another and do it all again in another 20K miles or so.

But I still stand behind my decision to get rid of the problem once and for all an go with the direct drive super fan that I got after the second failure of the electronic clutch. It has never given me any problems, my temperature stays in acceptable ranges in all weather and driving conditions, and I have had no adverse affect on fuel economy. And best of all, I'll never get stranded by an overheat caused by that worthless monument to planned obsolescence that they call a "viscous drive, multi-speed electronic clutch."

[the trainguy]

Thanks guys for taking the time to post this info!
A couple of questions....

Mine is a 2014,did they make any changes/improvements over the earlier ones or am I staring at the same problem in a few years.

I'm pretty mechanically inclined,is the direct-drive replacement fan assembly from the non oem vendor something that I can do?

When you go with the aftermarket fan/clutch what do you do with the sensor/electrical harness that connects to the variable speed clutch?
Just leave it tied back out of harm's way?
Does the ECM know/care that it's not there anymore or does something have to be reprogrammed?
Just looking to make a preemptive strike!
Thanks,
Bob

[bobguigley]

about a year after the fan clutch was replaced on our 2010 Damon Astoria, an inspection revealed that the engine had a leaking exhaust manifold.

When a Cummins shop serviced that problem, the exhaust manifold had to be replaced because it was warped........

Probably from overheated engine.

So there is a total of $5600 ($3300 for the clutch, $2300 for manifold) in repairs owing to that piece of crap fan clutch.!!

[finnaz]

Just had the Fan-Clutch replaced on our 2016 with 3000 miles!
ISB 6.7 340hp