That's the 2nd time I've heard of no timing marks on the internal cam gears...not common, as far as I've heard. What model car?

 

2001 40v

 

That's my engine...have never had the valve covers off this one, so cannot attest to their presence or absence....no leaks and no other problems under there...yet, knock on my head

 

absolutely! looking forward to seeing the DIY

 

are you sure there are no marks? One is on the bearing cap and the other is on the sprocket part of the camshaft.

Both markings are under the valve cover, neither is visible with it installed. If the engine is at TDC you should see them.

Here's a short video I posted on youtube on what I removed doing the timing belt. Fuel pump replacement is posted as well.

http://www.youtube.com/watch?v=MniODl1kLYA

Bob

 

There are NO timing marks on the camshafts, this is impossible because once the camshaft sprockets are broken free (gear puller) they will freewheel. They aren't keyed like on many other cars, thats why the cam bar is needed in the first place. As for locking the crank, only about 5% of flat rate mechanics will do that, so its possible that your belt was off slightly, it does look like that crank plug did get rounded out a little though. Personally i have never locked the crank in place on any audi engine when doing the timing belt, but i recommend it to anyone thats never done the job before, but the cam bar IS necessary.

Great video A8CT! You have had quite the collection of A8s!

 

That is interesting Auditech, I have the triangle marks on the bearing block, and according to my manual there should be corresponding marks on the (can't remember if it was the camshaft itself or the sprocket, it was a couple of months ago that I went through this).
So the question now is, if I take it to an Audi mechanic to have the timing fixed, how will they do it without any marks, and should I grab my ankles and back up for it?

 

Ugh, the end of the camshaft has a slot on it that the little ears sit on, this is what the camshaft bar locks onto. The holes on each ear are different sizes, the small ones are 180* off from the crank when they facing away from the engine, hence the cam bar WON'T attach to the ears when its 180 degrees off. The larger holes are the same size as the pins on the inside of the cam bar, so if the bar locks onto both cams the crank HAS to be in time at TDC, unless the previous tech messed it up. What professional techs do to make the job easier (without locking the crank) is to loosen the cam pulley bolts about 2-3 turns, then use a pulley puller and pop the camshaft pulley off the camshaft itself so it will freewheel on the end of the cams. This makes it 1000X easier to pull the belt tight and you don't need to have the cam bar on the engine when they are broken free because the cams can no longer move with the pulleys. I don't know why there are arrows on the bearings, but it shouldn't have anything to do with the timing.
Any audi mechanic can do a timing belt change with his eyes closed, the fastest i did an A8 timing belt job was about 50 minutes......it leaked coolant but thats besides the point LOL!

 

Here is a link to the factory sprocket gear puller we use. http://www.amazon.com/VW-Audi-Cam-Sp.../dp/B000RT89YS I almost never do a audi/vw V motor without one, its a pain in the *** to get the belt tensioned correctly without one.

 

ok, so you see the triangle marks on the bearing cap that's good. If you look right behind the cam sprocket (that connects via the chain to the other cam)....you'll see a tiny rectangle stamped behind the sprocket on the cam itself. Lining up these two marks means your cams are where they need to be.

There aren't any marks on the "main" cam sprocket (not keyed as auditech says) or on the part of the camshaft that extends beyond the tensioner.

Auditech, are these marks only on the 4.2's? I have an extra head and some camshafts on the bench along with my old tensioner. I was going to shoot another youtube video so people could get an idea on cam tensioner and/or gasket replacement.

You'll be able to see them clearly then, maybe I'll do that later tonight if I have time.

thanks for the compliment on the video, I got one of those $100 pocket camcorders in a raffle and never thought I'd use it. It's a great tool to have around the garage, I'm using it all the time now.

Bob