I'm going to be doing a timing service on a 2001 (D2) A8L with a 4.2L engine on Friday. I'll be taking pics along the way and will probably put together a DIY for doing it.

I know this car is typically seen as a different tier in the car spectrum in that many owners don't DIY the maintenance as they do on the lesser cars in Ausi's lineup, but there are enough of them owned by forum members that it seems the DIY procedure would be worth it to have.

I'll most likely put it together anyhow but if it's something that any of you would like to see, just reply and let me know and I'll make a point of doing it sooner rather than later.

 

I'm all for it.

I've already done my own ('01), but have trouble finding any online info on the 40V for other posters...already lots of documentation of the 32V procedure (very different in many ways) at AudiPages and other sources.

I took a few random shots of mine, but nothing comprehensive...just to document how much space was available with the front end in place.

Even when using the Bentley manual (which I highly recommend ALL D2 owners get, mechanics or not), photos and personal experience are priceless.
Really not that tough of a job for an average mechanic and they'll save a fortune.

Looking forward to having a complete DIY tutorial available for other future DIYers.

Thanks,
Sam

 

I did my own recently, but I'd certainly be interested to read it, might even see something that makes it easier next time around.

 

Sounds good guys. I'll take the pictures during the process and get it written up. Do either of you have any tidbits of advice to pass along that you learned from doing yours? This'll be probably my 15th timing service on modern Audis but the first 40v 4.2L and the first A8 that I've done. I'm very familiar with the methods and thought processes that have gone into the design of these cars (I've done 12v and 30v V6 as well as AEB and AWM 1.8Ts in the B5, the ATQ in the C5 A6, and the AMB 1.8T in the B6 A4), but each model has its quirks and little details that you discover during the job. Did anything jump out for either of you during your R&Rs that might be helpful? TIA if there's anything to pass along.

 

Well, I'm at the "minimalist" end of the scale that makes "by the book" mechanics shiver

I REALLY do all the critical work and most steps by the book (you have to), in that everything ends up back where it belongs and works perfectly later...nothing has EVER come back to haunt me following a T-belt job on any German car and there have been many VW's, Porsches and my present D2 40V.

I never remove the front end, since I've found that there's plenty of room for me to do all critical work, including adjustments and proper torquing.
I also never remove timing gears, since I've found that the belt slips right off easily when tension is relieved and back on with no problem...esp since it hurts nothing internally to turn cam belt gears slightly back and forth to fit the new belt onto proper teeth. I mark the old belt and all 3 gears (crank and cam gears) with paint, transfer marks to new belt and refit that way starting at the crank gear, which I do lock in place just for peace of mind..but do not use cam gear locking tool...between paint marks and double checking cam gear timing marks with a straight edge, I've never found the need for the tool.

Even doing it the traditional way, I can stress a few of points:

- Have no fear of either cam gear springing out of place or moving either a bit for belt fitting needs...without engine running, it is near (if not completely) impossible to do valve damage by moving these.

- The body attached portion of the engine torque support need not be removed (front end removed or not) during the job...rubber donut comes out easily first, then engine attached portion comes out easily (required) ...enough space to remove or drop out of the way, even with the front end in place.

- Use a Bentley or Elsa manual to double check your steps and final adjustments. EVERYONE SHOULD HAVE A MANUAL!! ...no excuse...you are NOT a mechanic of any kind if you do not have this tool.

 

Did the job today and in all it's actually less labor-intensive than an A4. We did put the car in somewhat of a service position (less so than on the 4 due to the AC and power steering lines on the driver side, but still opened up). This was to allow more room to work and also, since the car belongs to a friend and it's the first belt job we've done for him, we wanted to get in there without hindrance so we could clean the engine, frame rails, and everything else we could reach.

Impressions and notes (which I'll include in the DIY):

1 - watch out when using the torque specs for the timing components. The torque specs listed for the idler roller on the passenger head between the water pump pulley and passenger exhaust cam sprocket, and for the tensioner roller (tge one incorporating the relay arm, actuated by the hydraulic tensioner, NOT the eccentric roller on the driver side above the crank, may be reversed depending on your source of info. It was in ours and I read online that the Bentley may have it reversed as well. It was listed that the idler torque was 33 ft-lbs and the tensioner roller was 15 lbs. This is incorrect - the idler roller is torqued at 15 and the tensioner is to be at 33. Take that to the bank - the bolt we snapped off on the idler (thankfully protruding from the head) can attest to this. We were able to extract it and picked up a replacement at Advance. For reference in case anyone else does this (this car was a 2001 A8L with the AUX 4.2L), the bolt is an M8x52. We got an M8x50, which works just fine.

2 - we did end up removing the torque mount from the engine but not the three upside-down bolts that attach the other half to the passenger frame rail. It partially covers the hydraulic tensioner.

3 - going to service position is easy. There's virtually nothing that's a pain, other than trying to keep past A4 experiences from skewing us into taking things apart incorrectly or excessively.

4 - just like the A4 and A6 (predictably), if the engine is indexed properly, the cam locking tool is only needed if you're changing the seals. It's not needed if you aren't. The engine will not spin when belt tension is removed.

To you guys above, I appreciate your comments - they did come in handy today. We got a lot of pictures of some of the steps and a ton of the engine itself, and where relevant to the DIY they'll be included. I'll also post the additional engine pics at the end in the event that they'll be a help as a reference for someone. I'll start putting it together this weekend.

 

Great...lookin forward to a needed addition to the online library.

Notes on notes:

1. My Bentley D2 CD Rom has these torque settings correct: 22nm (16.22 ft lbs) for the idler roller & 40nm (29.5 ft lbs) for the tensioner roller.

2. As I wrote above, yes it IS required to remove the "engine portion" of the torque support to put the grenade pin (or 2 mm drill bit) in the damper AND later to measure your final 5mm damper piston extension, to assure correct tension applied by the eccentric roller.
My point was that the "body portion", as you wrote, need NOT be detached...AND for those choosing to leave the lock carrier in place, there is plenty of clearance to remove the "engine portion" or drop it out of the way.

Again, TIA for documenting the procedure, verbally AND photographically.

 

Glad it all went smoothly for you, I was not so lucky with mine. I marked all the cogs and the belt and put it all back together accordingly, and everything runs great, except I have a check engine light due to cam timing faults, so I guess the job isn't totally idiot proof.
Shortly after doing that I replaced my valve cover gaskets and was hoping to check the timing marks on the camshaft, but believe it or not (I probably would have trouble believing it if it came from someone else) there were no timing marks on my camshafts!
I still haven't decided what I'm going to do about it, it's Winter in the midwest and I have no garage so working on it myself can wait, I also have less money through the Winter months so if I am going to take it to a mechanic that will have to wait too.

 

I'm glad to hear that Bentley fixed the error - apparently the earlier manuals were incorrect. Understood on the body mount as well. I really was pleasantly surprised at the ease of the job. It's nice to see that Audi kept serviceability in mind across the model lines.

 

Very true...T-belt even easier on the 40V than the 32V motors.