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

[GShail]

As the title of the thread says, this last fan clutch made it 35,000 miles. Previously they had been going out at the rate of one fan clutch for every 5,000 miles. I have made several posts regarding this issue and followed many generous pieces of advice, and it seemed to be working . . but here I am again.



The delaer will not replace this latest fan clutch because it has been more than 12,000 miles since it was replaced. So tonight I am going to replace it by myself with the spare I have been lugging around for 5 months.



Question? Does the big nut on the fan clutch have left handed threads?



Looks like I need to use my fan clutch tool to hold the pulley tight and then if I am facing the engine straight on turn the big nut on the fan clutch to the left as in left loosey? or is this fan clutch reverse thread like a GM?

 

[Vaughn MacKenzie]

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

 

[mwdean]

the fan clutch is right hand threads on common rails, it is left hand on 1st & 2nd gen engines

 

[MMeier]

Right hand threads George, where this one leave you stranded at? Anyone know of an aftermarket replacement for these things? How many miles are sitting at presently?

 

[GShail]

It goes on like crazy and then goes off and doesn't come back on. When you test it later on the DRB it says fan clutch Pulse Width Modulation 100% but rpm is low.



As for being reverse thread, that is what you say, but there are some posts that say it is left.



Which is it? Reverse or LH thread.



When I am looking straight at the motor from the front and I have the pulley locked Which way do I turn the nut left or right?

 

[GShail]

Presently at 195,000 miles

 

[rbattelle]

When I am looking straight at the motor from the front and I have the pulley locked Which way do I turn the nut left or right?

ROTATE THE NUT COUNTERCLOCKWISE (TO THE LEFT) TO LOOSEN! This is called "right hand thread". Refer to page 7-41 of the 2003 service manual.



-Ryan

 

[GShail]

Thats what I am doing, dang she sure doesn't want to come off. lol

 

[rbattelle]

Thats what I am doing, dang she sure doesn't want to come off. lol

The mounting nut torque spec is only 24 ft lb!!!! Maybe that's why you've had so many failures? The knucklehead mechanics are cranking the nut down super tight!



Here's what the service manual says for removal:

The electronically controlled viscous fan drive/fan blade assembly is attached (threaded) to the fan hub shaft. Remove the fan blade/fan drive assembly from fan pulley by turning the mounting nut counterclockwise (as viewed from the front). Threads on the viscous fan drive are RIGHT-HAND. Place a bar or screwdriver between the fan pulleyu bolts to prevent pulley from rotating.

At the end of the install procedure is a bold paragraph:

NOTE:

Viscous fan drive fluid pump out requirement:

Aftrer installing a new viscous fan drive, bring the engine speed up to approximately 2000 RPM and hold for approximately 2 minutes. This will ensure proper fluid distribution within the drive.

Now, if a guy like Sag2 worked on the previous clutches I'd have confidence that this procedure was followed. What are the chances the guys who worked on yours were so competent?



-Ryan

 

[GShail]

Ryan, I would imagine that zero of the previous mechanics followed the procedure as outlined. I still can't get this thing off. The cheap fan clutch removal tool I bought from Autozone is made of weak metal and the jaws of the wrench are bent now. The rental tools they have on hand are made of black metal but are really hammered and do not fit either. Only 24ft lbs on the mounting bolt? Holy moly this thing was put on by superman it will not budge. Going over to a buddy's in the morning, he has a sweet fan clutch removal kit from MAC, hope it will work.

 

[MMeier]

George, what used to work for some on other units is to use a long punch and smack that damn nut hard, make sure you get it on the right side, and that the punch can not go flying off somewhere it shouldn't, radiator comes to mind.

 

[TRAMPLINEMAN]

Different years, but I've had the same issues with my 97. I'm on my third clutch in 20K miles. I bent a couple of those tools trying to remove the original clutch. I bought a large pair of channel locks to hold the hub while turning the nut. Works great. My third one is not working now. Never comes on. I've done the same procedure on all of them. Let stand upright overnight. Install the next morning and run at 2000-2200 rpms for two minutes. They all work great for shorts periods of time, then just quit.

 

[GShail]

Unfortunately there is not enough clearance for channel locks. My big fella won't even come close to fitting in there.

 

[HOBrian]

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

 

[tkerrigan]

On removing the fan nut, on a 1st gen I used a hacksaw to cut one more notch on the sliding part of a 15" crescent wrench. Put the belt around the sheave and clamped it lightly with visegrips. Apply modified crescent wrench and smack smartly with 1 lb hammer in proper direction. Came loose on third smack.

 

[rbattelle]

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

I agree. This is too much trouble, GShail.



-Ryan

 

[betterthanstock]

It goes on like crazy and then goes off and doesn't come back on. When you test it later on the DRB it says fan clutch Pulse Width Modulation 100% but rpm is low.

Some 03's have a problem with the wiring rubbing in the lower corner of radiator, behind plastic shroud. Make sure it's not shorting it out causing it to stay on all the time, or something bizarre like that.

 

[GShail]

Well I wasn't able to get with my buddy to use his nice fan clutch removal tool. So instead of waiting and doing nothing, I used some farmer ingenuity and reengineered my cheap fan clutch tool from Autozone. I put the wrench in a vise and pinched it back to 36mm, and welded a small square piece of steel to one side of the wrench. Then I trimmed the square piece to match the shape of the wrench and ground off the rough edges. Presto chango a new reinforced fan clutch wrench that did get the job done.



After that torqued the big nut to 24 lbs and followed the break in procedure (Thanks again Ryan!)



Now I have nice cool AC at idle and no hint of an overheating problem climbing grades with the heavily loaded trailer. BAck to business. For now. LOL



Hope this one makes it for a good long while.

 

[MMeier]

^^^^^^^

 

[rbattelle]

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