Help on timing belt replacement - D2 A8L

[Gaffer]

New to Audizine and looking to become an active member. I inherited a 2001 that has sat for a couple years. Am working with a friend who has extensive mechanical experience, but want to assure the cams and crank are set correctly on a timing belt replacement. Seeing a lot of threads around various timing belt kits and such, but not any specific guidance on the replacement itself. If someone has done this job and can offer their insight into how the cam and crank gears are set dead on correct, much obliged for your reply.

I bought the Bentley manual, which references a few specialty tools recommended. Are they absolutely needed, or can this job be done with some clever "McGuiver work-arounds?"

Thanks, John (c - 703-283-6100)

[moyenecorniche]

You need to post this in the B5 section but also what model in the 2001 line ?

[rollerton]

4.2 in the D2 A8/S8 is tpretty much the same as in the C5/A6. Special tools needed? Nothing totally critical, but the cam-lock bar definitely makes it easier/ safer. Procedure is pretty much the same as the 2.7/2.8 V6 engine too.
Pull the front off / service position, take it apart, lock the cams and R&R the belt + water pump + t-stat and anything else worn out or suspicious. You might consider doing valve cover gaskets, chain tensioner seals too, those seals would be slightly easier to get to if you're in the middle of the big service. And then it's all fresh for many years.

[27litres]

If you follow the procedure in Bentley you will be fine.
Due to the lack of timing marks, the most important thing is is to align the cams and lock the crankshaft, the rest is reasonably straight forward.
You can hire the alignment tools in NA without having to buy them - can't think who hires them (I'm in Aus, so it's irrelevant to me ;)) - ECS or FCP maybe?
Make sure you replace the water pump (with a good brand - Geba or Behr or similar), as you have to pull the belt off to access it anyway. Also do the thermostat for the same reason (can be done without removing belt, but you'd really not want to have to do it).
The kits usually come with new idlers and tensioners - use them!

You need to post this in the B5 section

Really?
For a D2 A8L with a 4.2 V8?

[27litres]

You can hire the alignment tools in NA without having to buy them - can't think who hires them (I'm in Aus, so it's irrelevant to me ;)) - ECS or FCP maybe?

Blauparts:
http://www.blauparts.com/proddetail....od=N1A1017%2DA

They want you to buy one of their timing belt kits though...

[BrianC72gt]

I used the crank lock bolt and the cam lock bar. It always drove me crazy that cam marks weren't visible, but if you pull the cam covers, the marks are visible just next to the crank sprockets...a little whiteout helps. If you didn't have the bar and wanted to confirm the marks, there they are, but then it hits you...Hey while I'm in here, why not change out the shoes on the VVT assemblies, which of course will require you to pull the cams or try some shenanigans to squeeze them in without pulling the cams entirely. And it was on this slippery slope that I ended up pulling the heads, checking the guides, dropping and lapping 40 valves and replacing the stem seals. Moral of the story: Rent, buy, or borrow the tools, because then you won't have that gnawing urge to pull the cam covers- just to make sure - for no good reason...it is cheaper in the long run. I was inspecting for damage after a failed tensioner, but still, it is much easier when you can just secure the crank at TDC on 5, secure the cams, and know that it has to be right because it was all locked down.

Build your own package of parts rather than rely on any one vendor for a "timing belt bundle". Don't cheap out on either the water pump or the thermostat (change it now...a bitch to get to otherwise...and they both fail). OEM on both of those- or at least OE supplier. Beauty of the D2s is the last one was made just over 10 years ago, so the OE suppliers can now sell direct to consumer rather than exclusively through Audi. The trick is figuring out who those suppliers are for each part. 10 years from end of model run also seems to be the trigger for falling prices at the Audi parts counter, so it is all good.

Opinions vary on whether you should replace an OEM tensioner or idler with a replacement one. I did. Many don't. Same for the crank and cam seals. I changed all mine last time in at 150k or so, but many are still running the original ones. But search some threads on the Brand of water pump...I forget if OEM is plastic or metal impeller... my brain is full and shit like this is forgotten almost immediately.

[MEDEL51480]

The EASIEST way to ensure timing belt timing if you don't have a cam lock bar or crank lock is this method that I've beeing doing for years.

1. Before you remove the old belt or pulleys, set engine to TDC
2. Mark 3 areas with a long line over the gear and belt: a. crank gear and belt b. left cam gear and belt, c. right cam gear and belt. It helps if you use 3 different colors to identify each line, or a simple 1,2,3; a,b,c; i, ii, iii next to each line will do.
3. Remove the belt and everything else you were planning to remove.
4. Take the old belt with the markings, and match it up to the new belt. Transfer the markings onto the new belt making very careful that the tooth count between each marking matches identically to the old belt (you can manually count teeth to be sure).
5. Once you're ready to install the belt (and have the pulleys and tensioners in), simply match the markings on the new belt to its respective timing gear.
6. With all of the timing components installed, manually give the engine a turn to make sure all gears go back to perfect TDC at every 720 degrees.
7. Voila! You're timed!