Camshaft Oil Seal Replacement
 

My car (2000 A4 Quattro 2.8L V6 30V, 196,000 miles) makes the Exxon Valdez look like a model of environmental stewardship--I have serious oil leaking from both front sides of the engine. All the crankcase ventillation stuff is OK and I've changed all the oil seals, cam plugs, and gaskets (including cam tensioner) except the camshaft and crankshaft oil seals. I'm going to do some UV dye/UV light work to verify the source of this problem but I'm pretty sure it will turn out to be the camshaft oil seals.

It looks like Audi doesn't use keyed cam sprockets so I assume I will need some special tool to position/hold the camshafts when I pull and replace the seals. The problem is when go I looking for the tool I don't see one listed for my engine code (ATQ).

Two questions: 1) Do I need a special tool to properly position the cam sprockets on the camshafts? 2) Where do I find the tool?

You need the bar and pin, same stuff for all Audi 30v engines.
You might take another look at the cam tensioner seal on the driver's side (bank 2) for leakage. If the surface is not cleaned or the seal isn't installed correctly, it will leak.

Not sure how old your timing belt is, but this would be a prime opportunity to replace it.

I know I need the cam lock bar (the long bar that spans and attaches to both cam spockets) and crankshaft lock pin to install the timing belt. But don't I need a tool to properly position and lock the cam shafts when the cam sprockets are removed? It looks like this tool attaches to some flats on the camshafts. Yeah, I know, I need to buy a Bentley manual.....

The tool attaches to two plates that are keyed to the cams. The sprockets are free to spin once loose...even with the bar locked in place. The bar locks the cams, not the sprockets.

Timing is infinitely adjustable! Make sure you free the sprockets and set it correctly.

Please pardon my ignorance, I've never done this before. I need to remove the cam sprockets in order to replace the camshaft oil seals. I assume the cam lock bar can't be in place when I pull the cam sprockets. When I pull the cam sprockets what keeps the camshafts from moving around? Or can I access the oil seals with the cam lock bar in place?

Do you think it's worth trying a vented oil cap before I tear into this? I've put a gauge in the dipstick oil tube and just don't see any pressure.

When I replaced the cam tensioner seals I was pretty fussy about cleaning things and putting sealant only where it was recommended. But my UV dye and UV light will hopefully show me where the problem is.

If you remove the upper timing belt covers, you should be able to see the cam seals. If they are leaking, it should be wet under either one of them. The lower seal will leak right around the upper oil pan, so you should be able to isolate which seal it is. For the cam seals, you need to remove the timing belt and loosen the cam sprocket bolts slightly and use the VAG sprocket puller to pop the sprockets loose. The lower crank bolt is tight, so you need the crank pin to lock the crank. The crank bolt needs to be replaced also once its removed. And as posted earlier, if you're doing this job, then its time for a timing belt, since you going through all the work to get at the seals. Tensioner, tensioner roller, water pump and belt roller should be checked or replaced also, if it was don;'t recently. Just to note, some engines had rubber seals and newer ones had Teflon seals. If you end up with Teflon seals as replacements, you will need the seal installers as well, as they are not like rubber seals and if they are over stretched or nicked, they may or will leak again, so keep this in mind.

The cam locking tool number is VAG 3391
The crank locking pin tool number is VAG 3242
The cam sprocket puller is VAG T40001

The cam sprocket bolt is torqued to 40Ft/lb
The crank bolt is torqued to 148Ft/Lb + 180 deg turn

I just did this today, so the numbers are still fresh in my head, LOL

Loosen the bolts with the bar in place, then remove the bar and the little plates behind it to get the sprockets off and change the seals. Do not turn the cams. They may turn or "jump" on their own, but you can just turn them back a few degrees.

I think that's a hack repair. Fix the problem.

You may have a leak from the cam adjuster seals. If the gasket is not installed right they will leak like crazy (high pressure leak)

Or two out of the three of them on the front of the engine...

OK, I think I've got it--the angular position of the camshafts is not fixed while I'm actually pulling and replacing the camshaft oil seals. I assume I need to do this with the engine at TDC?

Thanks so much for your help.

Yes. That's what the crank lock pin is for. It pins that crank in the correct position.