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99BlackB5
04-30-2013, 05:03 PM
Hey guys, serpentine belt snapped yesterday and today I went to replace it and realized the smooth pulley below the alternator attached to the vicious fan is seized up. For one I can't even find exactly what this part is called and two does anyone know if it is possible to replace without removing the front end?

walky_talky20
04-30-2013, 06:34 PM
The viscous fan pulley bearing is replaceable and available separately:
http://www.ecstuning.com/Search/ES277600/ES277600/

Yes, you *can* replace it without removing the front end. You have to drop the fan off the front, remove the alternator, flop the power steering pump to the side, and remove the entire bracket from the car.

Once you have it in hand like this:
http://i241.photobucket.com/albums/ff90/madcircle31/part.jpg

Then you can change the bearing. I've never changed one myself, but I'm assuming it needs pulled out and pressed in.

There is "some" room to work with it on the car, but I think you'll be hard pressed to change the bearing without either removing the front end of the car, or removing the bracket from the car.

99BlackB5
04-30-2013, 06:58 PM
The viscous fan pulley bearing is replaceable and available separately:
http://www.ecstuning.com/Search/ES277600/ES277600/

Yes, you *can* replace it without removing the front end. You have to drop the fan off the front, remove the alternator, flop the power steering pump to the side, and remove the entire bracket from the car.

Once you have it in hand like this:
http://i241.photobucket.com/albums/ff90/madcircle31/part.jpg

Then you can change the bearing. I've never changed one myself, but I'm assuming it needs pulled out and pressed in.

There is "some" room to work with it on the car, but I think you'll be hard pressed to change the bearing without either removing the front end of the car, or removing the bracket from the car.

Turns out someone told me this is called the idler pulley. Does this same bearing make it spin which is why it is seized up?

walky_talky20
04-30-2013, 07:08 PM
Calling it an idler pulley is not really correct as it is a driven pulley that performs a function (spinning the viscous fan). An idler pulley is so-named because it has no function of it's own: it just "idles" and serves to route the belt. Perhaps if you "deleted" the viscous fan in favor of an electric one, then you might call it an "idler" pulley. But this is really just semantics.

The bearing I linked is the one the one you are dealing with, yes.

99BlackB5
04-30-2013, 07:25 PM
Calling it an idler pulley is not really correct as it is a driven pulley that performs a function (spinning the viscous fan). An idler pulley is so-named because it has no function of it's own: it just "idles" and serves to route the belt. Perhaps if you "deleted" the viscous fan in favor of an electric one, then you might call it an "idler" pulley. But this is really just semantics.

The bearing I linked is the one the one you are dealing with, yes.

Looks like this is the part that isn't spinning - http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Engine/Cooling/Fan/ES6891/ . Does the bearing drive that pulley? Because the fan can spin fine but that pulley itself is locked up real tight.

walky_talky20
04-30-2013, 08:30 PM
Yes. That black pulley bolts directly to the viscous clutch (which itself bolts to the fan). The pulley/clutch is bolted directly to the bearing that I linked. That is what mounts it to the accessory bracket and allows it to spin freely. If it isn't able to spin, the bearing has likely failed.

Artiemas
05-01-2013, 06:15 AM
I still have my viscous fan, and am actually waiting for a good excuse to replace it. It is a little noisy, but I've yet to find it detrimental to anything besides a louder fan. Maybe I'm just being a glutton for punishment.
Anyways, my original point to this post is to really say that instead of replacing that bearing, just go EFK. From what I've heard they're quieter and just easier to work on the front of the car with the front lock carrier still attatched.

Some vendors sell kits for about 2x-3x the amount you could make your own with. I think some people have theirs on a manual switch, or a temp sensor into their radiator. Or some people just have them permenatly powered.

walky_talky20
05-01-2013, 07:44 AM
An electric fan conversion would negate the need to fix the bearing. See here:
http://pictureposter.audiworld.com/24446/dsc02167.jpg

As an added bonus, it will make the car idle quieter. All the better to hear that lifter tick and chain tensioner! Har, har, har.

Manual control is asking for trouble. Wiring it to come on with the low speed of the existing auxiliary cooling fan (first thermal threshold of the dual thermal fan switch) would probably work well. You can't just tag on to factory wiring, though. You must add your own wires, relay, and fuse. Just use the factory signals to trigger.

Mad Cow
05-01-2013, 09:44 AM
What temperature does the stock switch trigger at? I've spent too much time trying to dial in my adjustable fan switch and the thing just sucks in general.

walky_talky20
05-01-2013, 10:10 AM
Stock switch lower threshold kicks in at 95C, and doesn't open until it cools to 84C. High threshold kicks in at 102C and doesn't let up until it cools to 91C. This is written as:

95-84/102-91c (http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Engine/Cooling/Fan/ES1694/)

There are cooler switches available that drop in (for earlier A4's that use the 3-pin switch, anyway). These are borrowed from older Jetta and Vanagon models (it seems the Vanagon often gets pilfered for it's temperature switches!). The vanagon switch thresholds are:

85-74/93-82c (http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Engine/Cooling/Fan/ES1695/)

That would keep your fans running much more often, and may be too drastic. I guess you'd have to find out.

There is an even lower temp version available, if you roll like that:

75-70/82-77c (http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Engine/Cooling/Fan/ES1696/)