MP4.2+6.0

Starting this as its own post so it doesn't dilute other quality write ups.

So out of curiosity on the D3 4.2, has anyone tried to do the belt job and NOT pulled the front clip? It struck me as I read the write up how many of the steps and pics ended up on that, even though it proceeds reasonably quickly.

I ask because I did the job with no clip pull on my 2000 A6 (C5) 4.2, and I had the belt off two other times for motor work. I never pulled the front clip. That started back with the 1996 A6 (C4) 2.8 for me, which also had a belt of course and which used the identical tools--both motors are 90 degree set ups with the same cam centerline spacing (not a coincidence). In the C4 case, IIRC it didn't even mandate pulling the front clip in Bentley. Thus I was used to it; way back on C3 I5's and on old VW first gen. four bangers you wouldn't pull clip either, and on the earliest there was no clip but rather some steel body stuff.

For the C5 4.2, it did say to pull the clip as I recall, but I love trying to skip overblown Bentley steps that read concisely: Step 1, go to some other section [for a little added fun], but hey we can say it in two lines so it looks short...until you flip over to the "other section" and find three pages of steps and pics, more than a few of which basically are saying pull motor or tranny or some huge subassembly.

On the C5 4.2, it had a clutch fan between the motor and radiator area, and by pulling that I got about 2-3 inches min. space in the tight areas, and usually 3-4 inches. (Yes I know there is no clutch fan on a D3; read on.) The first time I did it, I didn't know how to release the inner pancake electric fan beside it, but later figured that out--which opens up the whole crank area you need for the hydraulic tensioner change out.

Even if it hasn't been done, probably the key feasibility questions are do you have 2" plus of space between the radiator and motor at the tightest areas, and can the electric fans come out without a radiator/clip pull? I know the clutch fan from the C5 is not present on the D3 4.2, but I don't know if they put the fans onto a rectangular housing with can't-get-to-them bolts on the D3 or if like the C5 you pushed on some clips while rotating the circular fan housing and it all came out. On my D3, I have also done the write up on both the water pump and the A/C compressor pulley jobs, and likewise front clip did not come off. Tight, but I did it. W12 motor is short front to back (but a mile wide) and has no front timing belt drive space, but does have a bigger capacity cooling system.

It took some tries to figure out and get acclimated to the steps on my C5 4.2, but once I did, I was at the timing belt maybe 45-60 minutes in. The clutch fan was actually the hardest because of the classic issue of trying to undo bolts on a quasi free spinning shaft that you couldn't hold with normal mechanics tools; once I got the special fork tool and thin wrench for it, that was straight forward. And yes, you do get some scraped knuckles from the tighter clearance to the radiator fins if you don't have gloves on--assuming fans come out and they are between motor and radiator).

Jack88

I shifted the clip forward a couple inches after removing the front bumper. It was a little tight at times but not bad. Nice to not have to remove radiator hoses or do a full drain. Still lost a gallon.

Mister Bally

Before I did mine, A co-worker's cousin said he did his without removing the front fascia or even moving the front clip forward. It took him a long time and he damaged quite a few knuckles.

Myself, I moved the front clip forward two or three inches. Twice as I've replaced two timing belts now. First time took me about 8 hours spread over three days. The second time was maybe 4-5 hours with my son & I both doing the work. He also helped the first time.

I had to replace my radiator in the winter of 2013-14 so I took more off of the car for that than I did for the timing belt work. Plus I had to add a hose and hole through the radiator housing per a TSB as the new radiator has an additional hose connection port.

mishar

Removing the front end is much much easier than it looks so there is absolutely no point to do it any other way.

GradecEngineering

I'm amazed that someone with such mechanical ability would shy away from spending an hour pulling the bumper off and the clip forward a bit. You must have steel knuckles. It's not just a matter of accessibility, but also visibility.

richard-tx

As far as I am concerned the whole thing boils down to how much time do you want to spend. Changing the timing belt could be done without removing the front grille, etc. but why would you? It will take longer, be more difficult, etc.

It reminds me of the time when my father was determined to change points and condenser in a tractor magneto. Everyone just took out the two bolts and put the magneto on the bench to service it. It literally took about 3 minutes to remove the magneto, another 10 to replace the parts and another 3 minutes to install. He spent about 2 hours doing it while on the tractor.

There are many ways to do something. Choose wisely.

MP4.2+6.0

FWIW, on reflection I deleted my other replies that tried to stay on the specifics of what would be involved. Instead, Uncle. Too bad in my book if people want to go with "conventional wisdom" and not explore new areas. I was also asking for practical knowledge about D3 fan and shroud mounting that underpin the alternate theory. That went unanswered, though Mister Bally did have experience w/ the radiator itself. It was more time effective on the C5 in my judgment, and way more than a little Audi wrenching experience. But lots of conventional wisdom there that says move clip to service position (and break the headlight squirters along the way for a little more fun). This is a different fan set up, so I was asking the questions.

Given interest toward dismissing it, inferring maybe I am not Quixotically time effective and other things, oh well. I have end run more than a few things that are conventional wisdom with convoluted overdone "Art" jobs. Biggest picture, seems sort of obvious to me the existing quality of various prior owner/mechanic/dealer jobs have issues, owners are scared by the cost and complexity of it, buyers take advantage of work not done in driving down prices, no one in an apartment or many condo settings can probably begin to take apart half their front end, etc. All ideas behind asking a "Plan B." I think some are underestimating the clip pull time but thats a lesser nit--I put it at over an hour for work connected to wheel and fender liner R&R even with new push pins and an intact belly ban set up. Uncle, Art.

GradecEngineering

MP4.2+6.0, I know you like to poke fun at the engineering behind these cars with your "Art" references, but the situation isn't as bad as you seem to believe. You reference to "break the headlight squirters" tells me you probably never had a D3 front bumper off, unless you're working blindfolded. If you did, you would actually appreciate the design. Before my first removal, I assumed it would be a warzone back there, but to my disbelief it was easier than some VW's. All of the wiring/hoses are bundled and routed in a neat manner allowing for easy disconnecting.

Honestly, if it's taking you over an hour to pull your fender liners, I can totally understand why you're trying to save time.

MP4.2+6.0

Again, lets start w/ fender liners. Repair AND replace. It isn't a one way street of remove only in looking at total labor input of job, but often I can't tell with some of the everyday vernacular what people really mean. If you are removing two wheels, getting out the jack stands to do it safely in the DIY environment (no lifts), pulling liners, reinstalling liners, using new push pins to shortcut the mushrooming of the old ones, lining them correctly them up with a belly pan (that hasn't had the end fender fasteners torn out), and bolting on and torquing the wheels, yeah that's an hour by itself if I am realistic about it, and especially count the reinstall time that I wonder if it is being glossed over. Doing snow wheels twice a year and having to pull driver's side liners on either W12 or S8 to get lower air box out I think I have the drill down...even blindfolded frankly... The Nightbreakers indeed are sitting on the counter because I know it isn't just a 30 minute quickee, so I will combine it w/ some other liner pull item. Read again in context; I think what was being said was the whole clip work was an the order of an hour +. No, I'm not buying what I think is understating time, at high and experienced skill levels, let alone casual. Remove AND replace. My point on the liners is real world to say if one part of the job takes an hour +. Not two, but 30 minute type impressions you could infer of the part of the job if the whole front end pull routine is supposedly an hour I think likewise are rose colored glasses. Be clear too, I translate to solo DIY home environments with decent tools, not lifts in a shop with many tools right at hand and maybe helpers and such. Thus, how can the rest of it be so, especially if I try to stay on DIY environment, even if I bring in air tools+compressor for stuff like wheel removal which I and others doing these kinds of jobs likely have even at home?

Headlight washers--no I don't know since as I said more than a few times, I haven't pulled it. But on the C5, I got to argue with the dealer body shop when they screwed them up with a bumper cover pull and broke them. So, how much expertise is needed if even a dealer body shop messed that one up? And I have replaced the lines on my D3 to the squirters (as have others with all the different motors) when they get fragile with heat soaking. Yes, then I know where the lines are and how they are clipped and all. But then the lines do break as part of the overall system, likely more during incidental work having BTDT myself.

But, up to altitude. I don't own a belt one any more so I could just say have at it. However I honestly think the biggest value killer specific to port 4.2s is the belt area--not all D3's, not Audis or Euro luxo cars generically. We share in common other stuff like control arms, air ride, MMI screen etc. The work here is $1800 for decent indy from a variety of posts, or $800 for parts MOL from recent posts and select non dealer parts, plus DIY. I know some of these value killer questions on a W12 too, like the temp sensor and the front 02s. But I have good answers for them implementable by a good DIY'er with nothing remotely like a motor pull, or front end yard sale. But if I believed the shop manual or the internet echoes I would be hosed--as a few have been.

More importantly, I want us to be sober here. The readership of car forums beyond new car options, wheels, discounts and "floormats" and other pretty superficial stuff is as little as sub 1%. I think the belt job is at like 10% of the board readership, on a good day. The board readership has even changed yet more in recent years--ever younger, less likely to be able to do full on disassembly work in condo and apartment car ports (or even street). And, the underlying issues about belt perceived frailties is broader than sub 1%, and the spectre of well over a grand type known maintenance on cars with values of sometimes sub $5K is scary. Meantime, so we are clear, when I poke fun at Art, it isn't so much about the design. The general design is strong. (parenthetically though, lets be honest, the belt drive is a kludged mess with no good excuse for a buried thermostat or captive water pump beyond they kept sliding the design over from old V6 starting points while they made it ever more complicated) "Art" is actually really often the stereotype of "vee know best" and "by the book" and all that. So yes on an older vehicle where I think the by the book answer is driving a stake through values and perceptions, I'm happy to at least try to introduce some unorthodox thinking to it. I have good answers for that on a variety of W12 nuances, so a suck it up type answer that is expensive and way beyond most is not ideal. And my post started with a coupled technical question after all. I think I have the answer now...if I believe Bentley that has the Art think bias. I comes down to how the pancake fans are fastened in connection with the shroud, which I now suspect makes the other method not do able even if desired. I'll know better next time I look at mine, assuming W12 is just bulked up some at radiator mostly.

OberklasseA8

MP4.2+6.0 - I have no exp. in this but I salute you for trying. I can see lighting, mirrors, small clearance tools, and maybe a small camera can assist you in the adventure.

ian