This last fan clutch made it for 35,000 miles but is now caput! This makes #10

[john3976]

Sweet. I hope it holds together for you. It would be nice if you never have another problem - then you'd know it was probably incompetent mechanics screwing up numbers 2-10.



-Ryan

Lord knows it could never be a faulty part according to you DC is perfect.



Why was this truck not lemon lawed? 10 replacements of the same part.

 

[brods]

8. Educate, Don't Irritate. Generally, nobody enjoys posts that offer little or no information, contains emotion at the expense of reason, or attacks another party. And remember, it is entirely possible to agree to disagree with others . . . respectfully. Diplomacy, discretion and common sense should be your guides. A click to the private e-mail icon and an off-line discussion is suggested to resolve difference.

GShail, I hope this one lasts for you. If this one fails prematurely too, I’d certainly look for something other than the clutch as the root cause of the failures.

 

[GShail]

I have looked at every possible thing that myself and everyone on this board could come up with. There are numerous generous pieces of sdvice that have been followed. I have a sneaking suspicion that the big nut that holds the fan clutch on was overtorqued when they were installed at the various dealerships. AdditonallyI do not believe they broke the fan clutches in correctly. However it could definitely be something else. I will keep you all posted.

 

[MChildress]

That's a bummer. When you say they go kaput do they fail where they don't engage, or they get stuck "on" and roar constantly?



Every vehicle I've pulled the fan on is reverse thread. Dodge, Ford and GM. . . the engines spin the same way on all rear-drive vehicles.



Vaughn

My powerstrokes are right hand thread,you are right most have reversed threads.

 

[brods]

Gshail, you might want to double check the torque spec. for your year truck. The following quote is from the 2005 service manual.

5. Install the viscous fan drive assembly onto fan pulley

hub shaft. Tighten mounting nut to 115 N·m (85

ft. lbs. ) torque.

The bolts that hold the fan to the fan clutch are listed at 24 N·m which is 18 ft lbs.



Also from the 2005 service manual (note the reference to vibration). I don’t recall from your other threads, was the fan ever replaced?

CAUTION: The electronically controlled viscous

fan drive is vibration and impact sensitive, especially

at the electrical connectors. Do not drop the

unit.

 

[rbattelle]

Brods, his truck is an '03.



-Ryan

 

[Turbo1Ton]

I will second Ryan's information as correct. My '03 manual says 17 ft-lbs on the fan blade to viscous fan drive and 24 ft-lbs for the viscous fan drive to the water pump.



Jeff

 

[brods]

Sorry to add to the confusion. This complicated fan clutch is interesting. I was looking in the service manual to see how it worked and came across the higher torque spec. Having different torque specs across the years certainly lends some credibility to the faulty installation theory, but 8 different fan clutches from different dealers all being defective or installed incorrectly still seems like a long shot.



GShail, did you ever take apart one of the bad clutches?



Does anybody know how it works? I haven’t had a chance to read the electrical diagnosis section of the manual, but the mechanical section really did not explain it well. Does it have a magnetic coupling to a traditional fluid clutch? It must also have an rpm sensor built in as well.

 

[nickleinonen]

i know for sure when my fan clutch fails out of warrenty [1x already], it is getting electric's in place. . i saw on the weekend on the trucks show a duramax direct bolt in dual electric setup. . maybe something like that will come our way

 

[MPletchetero]

GShail,You might want to read DC Customer Satisfaction Notice #B28(03 tighten diesel engine cooling fan). The procedure calls for the cooling fan nut to be tightened to 85 Ft. lbs. same as 05 service manual.

Go to wwww.dodgeram. info then go TSB page and click US RECALLS . Read B28 03 Tighten Diesel Engine Cooling Fan.

 

[Amish Elegance]

Why not put two electric fans on and be done with this problem?

Thinking what he said.



However...

Any chance those who've replaced theirs multiple times have clogged fins? That would work the clutch harder. Just an idea.

 

[MMeier]

i know for sure when my fan clutch fails out of warrenty [1x already], it is getting electric's in place. . i saw on the weekend on the trucks show a duramax direct bolt in dual electric setup. . maybe something like that will come our way

But we all know that a duralax does not make enough power to generate any great amount of heat!!!! So it does not take much too keep one cool!! :-laf

 

[MMeier]

Why not put two electric fans on and be done with this problem?

Think this was covered here in great detail as to why electric fans would not be enough to keep our mighty Cummins cool, forgot how many cubic feet of air needs to be moved per minute, but the number was way up there.

 

[JHardwick]

My fan has been screaming down the road, sounds like it'll take flight any second!! It's almost always on with the AC on, and only on while pulling long grades with a load w/o the AC. Test says it shouldn't spin more than 5 times by hand while cool. Heck it spins more free while idling at temp, no kidding. After a full warm up, while idling, I could stop the fan by hand and spin it in reverse and it spun more freely than trying to spin it by hand cold



I really hate to spend $400 plus on a part that is good and only being fed bad info, seems the ECM takes reading from 3 or more sensors to determine whether the fan should lock up or not.

 

[rbattelle]

GShail,You might want to read DC Customer Satisfaction Notice #B28(03 tighten diesel engine cooling fan). The procedure calls for the cooling fan nut to be tightened to 85 Ft. lbs. same as 05 service manual.

Go to wwww.dodgeram. info then go TSB page and click US RECALLS . Read B28 03 Tighten Diesel Engine Cooling Fan.

Here's a link to that recall. Indeed it does say to go to 85 ft-lb. GShail - I think my service manual is wrong on the 24 ft-lb. Guess you better tighten it down like MPletchetero says.



-Ryan

 

[DMcGalliard]

temp is the fan clutch fully engaged?

Hello to all, thought this would be good thread to ask this question?

My 2005 will heat up at low speed, moderate load and it does not sound like the fan clutch is fully engaged. I have the Edge readout of temp and the temp will get up to 212 and I still don't hear the fan. Does it engage at a higher temp or is the clutch not working. It has not over heated,say 215 to 220 as I back off.

Would really like to know at what temp it is full engaged.



Thanks, Dave Mc,

Dawson, YK

 

[JHardwick]

My fan has been screaming down the road, sounds like it'll take flight any second!! It's almost always on with the AC on, and only on while pulling long grades with a load w/o the AC. Test says it shouldn't spin more than 5 times by hand while cool. Heck it spins more free while idling at temp, no kidding. After a full warm up, while idling, I could stop the fan by hand and spin it in reverse and it spun more freely than trying to spin it by hand cold



I really hate to spend $400 plus on a part that is good and only being fed bad info, seems the ECM takes reading from 3 or more sensors to determine whether the fan should lock up or not.

Update, it finally puked in Mass. last week :-laf $366 and no area dealer had time to do the install. An open end wrench and 18" water pump pliers works good after removing a pulley bolt to make clearance for the wrench.

 

[CPittman]

DMcGalliard - preface: my fan clutch was replaced under warranty at around 45K miles - try punching the AC on if you at low speed that seems to engage the clutch and cool it back down. If you're not sure, do what I did, let your dealer's service tech check it for you. The tech grabbed the fan with the engine idling (no AC) was able to hold it (wearing gloves). He said that if the fan clutch was within parameters he wouldn't have been able to do that. Have your tech check it for you.

 

[Turbo1Ton]

Well, I replaced my fan clutch this afternoon. I didn't ever have a tech look at it with the DRB III but I did hold onto it, with no effort, while it was running and I was able to spin it 5+ times when it was cold. The new one I couldn't get to spin at all. It would go less than 1 blade before it would stop.



It wasn't difficult at all. I don't think mine was ever fixed under that TSB. It was probably still torqued to 24ft-lb because it didn't take any effort to break it loose. However when I went to install it I was reading the TSB and I don't get it. I calculated it and if I use 42ft-lb of torque then using the fan clutch wrench that I have (which is 12 inches from the center of the 1/2 drive hole to the center of the head; same as they tell you to modify the wrench in the TSB) I only get 75ft-lb of torque on the fan clutch. Which, by the way, was impossible for me to get. I couldn't hold onto the breaker bar hard enough. I figure it is tight. I also put a little bit of blue loc-tite on there just in case. I'll also double check it in a few days.

 

[rbattelle]

I also put a little bit of blue loc-tite on there just in case.

Good idea.



Ryan