Redneck Truck

yup. my TDI has 2 electric fans. so did my firebird formula. why not?

spoon2000

Both my factory fans and the fan at the VW dealership were made by Gate is that's of any value. The one I ordered from RockAuto is a no-name, whatever's on the shelf brand; for a 10 year old car, I don't really care, especially since I now know how to diagnose and remove/reinstall and know that a replacement is only $80 shipped.

spoon2000

There's actually no reason you couldn't install a 4th fan in front of the A/C condenser/radiator on the driver's side. Look into the grille of any Caddy that's been converted to a limo, and you'll see a couple of these puppies http://shop.advanceautoparts.com/web...7CGRP2061A____ spinning around (of course, there are single fan versions available, too).

For what it's worth, RockAuto has already shipped my new fan, so I'm hoping it will be here tomorrow.

JoeM

Awesome, I wonder how different they are from the 4b3 959 457 fan that is listed for my car...

spoon2000

4B3 959 457 is the part number on my A/C fan (in front of the radiator) -- it has 13 straight blades. The aux fan (behind the radiator) is part number 4B3 959 455 and has 8 curved blades.

When I first called the Audi dealer this morning to ask what the part number was for the aux fan, I was given the wrong part number (the one for the A/C fan), and only when I called back did the parts guy tell me "Oh yeah, there's another fan listed there, too -- 8D0 959 455L." So you have to be careful about what part numbers are being listed for what application. Some parts breakdowns I've seen for the 4.2 don't even list an aux fan, and some listings for the 8D0 959 455 part number indicate that it's only applicable to the 4.2 starting in MY 2002, so some detective work is required. I'm praying that whatever FedEx brings tomorrow will be a direct fit, or at a minimum, that I'll be able to swap the motor and blade into the old fan mounting and attach the whole business to the radiator.

The 8D0 959 455 part number (which the Audi dealer gave me, and which was on the fan identical to my dead fan that I saw at my VW dealer down the street from me) is what I cross-referenced to place my order from RockAuto.

When I was at the VW dealer, I picked up a gallon jug of VW/Audi pink coolant -- part G-012-A8G-1G for $22. Considering that pink Pentosin runs about $10 plus shipping for 1.5 quarts, that seemed like a good deal, and it made me feel a bit less guilty about having made the parts guy drag out an aux fan from the warehouse so I could compare it to my dead one.

spoon2000

OK, so here's the deal... The fan arrived. It's made by Tong Yang Group of Taiwan. Seems well enough built, and the box says it's made for '01-'05 VW Passat and Audi A8/S8. Unfortunately, it's not an exact duplicate of the OEM version that I removed from the car -- it's about 1 inch thicker from front to back. Part of the extra thickness is in the blade, and part is in the motor, which looks beefier than the OEM fan motor (fine by me!). In any case, I got it installed by removing the cover from the timing belt to make a bit more space, disassembling the fan motor and blade from the support structure, and then first dropping the motor and blade into place and then dropping the support structure into place and bolting things together. Even then, the motor housing was extremely close to the exposed drive belt pulley, so I added some spacers (extra nuts) to the mounting bolts so the fan would sit a bit (like a quarter inch) farther forward inside the radiator and away from the engine. Seems to work fine. Pictures of everything to follow.

The bad news is that after replacing the fan, the car still has an overheating problem. As soon as the engine got up to operating temperature, the needle started to rise, and then the dreaded red thermometer with the obnoxious dancing waves appeared in the middle of the dash. I got out and popped the hood, and found that all three fans were spinning away full blast.

So... I think I'll replace the thermostat (which went bad once before a couple years back and caused overheating), and then if that doesn't work, I'll take the beast to my local shop for what I can only assume will be a water pump and timing belt replacement (the car has 85K miles and I don't think the water pump and timing belt have ever been changed out).

Any other thoughts or good karma?

joshe8695@yahoo.com

I believe you have to put it into service position to change thermostat. Perfect time to perform all maintaince.

spoon2000

At this point I'm actually half hoping that's the case. I'm loading Bentley eBahn onto a laptop as I type so I can see just how heinous the thermostat job looks. If the car needs to go into the shop, I'll likely be getting my own thermostat, timing belt, and water pump to at least save a few bucks there rather than pay whatever the shop would charge. And I'm not above pulling the bumper, etc. myself to save some shop time there.

Any way to tell if the water pump is dead in the absence of leaking coolant? And any way to tell in advance about the thermostat (I hear the old feeling the hoses trick isn't so reliable, because if the lower hose is cool, it can be from a stuck thermostat or from a radiator that's actually doing a really good job)?

spoon2000

Ugh. Looked at Bentley manual, decided pretty quickly to make an appointment with the mechanic. Timing belt has to come off, etc. And it may not even be the thermostat that's gone off the rails; better to let the shop decide at this point what's causing the ongoing overheating. MANY thanks to all for the assistance thus far.

Pete@ECSTuning

Oh no, don't give up! It really isn't a hard job and you don't need any special tools, well patience if you consider that a special tool...

The jobs is just time consuming and if you have a Bentley you can DIY it. From the sounds of it you are very mechanically inclined. Give it a go because at 85k miles you do need to do a timing belt, water pump and thermostat regardless.

Our Timing Belt kits start at about 420 and work their way up. They include everything, including seals that are commonly known to leak. Imagine what a shop would charge to replace all this for you! Click here for timing belt kits. You are so close, don't give up!

(Also that hose trick is a pretty good one in a pinch)