hunterp27

so as I reported a couple weeks back, I started chasing an oil leak thinking it was the lower oil pan gasket and this is where we have ended up. A fully extricated V10 from its snug little engine bay. It is probably just as well though as we uncovered a few things that have not fully matured into problems, but are well on their way.

1. Water drains are completely plugged with debris, leaves, dirt, grime and general grunge. I was not very far from having them back up into the car.
2. Two different heater hoses on the back of the engine were leaking with one of the large nipples breaking off inside the hose. Heater was likely days from stopping to work and probably contributed to the failure of my overflow reservoir that's being replaced as well
3. one of the threaded stays for the struts was completely stripped out from a previous removal. It was being held in place by the other two in the triangle formation.

Here are the pictures of the process taking place.

707chris

This gives me confidence if I ever have to remove my engine. Looks fairly simple comparatively to other engines needing partial disassembly for removal.

MP4.2+6.0

Quite the project!

Besides the things suggested a few weeks ago with your earlier post the motor pull would be necessary, given what it looks like you dropped in front it should be super easy to look at the upper control arms and other bits very carefully. If you are beyond about 40K on your arms, you might as well do them. With car down/up anyway, you can just do the bushing press in instead of the whole arm.


I forget if it was covered last time, but look at engine toque mount very carefully--the smaller mount in front of the main on on the passenger side of the motor far forward. Childs' play to replace right now, versus really big hassle w/ motor in. Several of us have lost them with (higher torque + power) W12's, so I would be cautious on the S8 motors too. I lost it even on my A6 4.2, though by then it was well past 100K miles and almost 15 years old. On my W12 it was done under CPO at about 75K and 6 years.

Given what you are doing with cooling system, I would change the basic sensor too. Problem area on W12, and some have lost it on 4.2 as well. Again, child's play w/ motor out.

hunterp27

MP,

what is the basic sensor? by the way i cannot recall if I reported earlier that the A/C condenser was ruined by the tow truck when he yanked it up onto the flat bed. That's another $440.00 on top of the project. fighting with the towing company now to get it ordered and shipped in time to arrive for reassembly. Lastly, I was down at the shop this evening right after they separated the transmission from the motor (this has to be done to get to the last few bolts on the upper oil pan) and they were attempting to remove the final two bolts on the driving disc/plate that's connected to the crankshaft. These two final bolts are stripped and we are now trying to figure out a way to get them out. I have never seen bolts that were this tight. the previous 7 bolts (made of grade 12/aircraft grade steel) have a star socket head and they rounded out inside when trying to loosen them. Gonna have to get creative to get them out.......all of the other bolts had greenish blue loctite on them. they don't want these coming loose inside the bell housing.

hunterp27

I wanted to add this picture in the first thread but was limited to 5 pictures. These are my drain plugs and as you can see they are jammed up bad.

halik

Hmm it seems your motor was out before, which would explain all the broken parts and stripped bolts.

EricVonHa

I don't know what kind of mileage is on the car. Though, it is easy maintenance to replace the O2 sensors while the motor is out. It is massively difficult to get to a few of them while the motor is in the car. If you can swing the parts cost, you'll save many hundreds of not doing them while the motor is in the car.

hunterp27

Halik,

The motor has definitely been out before but it was done by the Audi dealership in Florida. Don't know why it was out but I will comb the records again and see what i can find but it doesn't really concern me now that we are there. I do want to clear up the stripped bolts on the drive disc though. Those were not stripped previously, the place that has it now did it and they have to figure out how to fix it. Also, the the broken heater hose connections broke during the disassembly this time...and... a couple of the other parts are just very very brittle after all the heat/cold cycles. I can tell ya this, the previous job(s) that were done were on the sloppy side to say the least. Its always easy to just cover things up if you know that nobody is gonna find your sloppiness until a long time down the road.

MP4.2+6.0

I mean the basic sensor that drives the temperature gauge for the instrument panel, plus is critical for all the engine control computations. Should be on a water line in back of the motor. Just look it up in a parts diagram or Bentley for the S8. On the W12 it takes hours to do and only after you pul the intake manifold.

Sounds difficult on those bolts. If those are what I think they are, they are called tri-square bolts. "Tri" "square" yielding 3 x 4 points. If not similar to tri-square, then I suppose large Torx sizing. I have never studied the dimensions, but likewise I have run into some stripping issues with similar trisquare bolts for the wheel bearings and sometimes on Audi door striker plates. I have wondered if there are both metric and SAE versions of the tools with slightly different tip sizing. The metric ones are M10, M12, M14, etc. In general my experience is they have to be really tight in the trisquare hole; any slop or off angle and they do tend to strip. Some tools are better than others too; the Lisle set I had originally from the retail store was not very hard metal. When I have run into stripped ones, after trying other versions of the correct size in case one fits more snugly, I have tried to find a slightly bigger size of a similar tool and just drove it hard into the hole with a hammer, then wrenched on it. I sacrifice the tool if needed where the part is critical like this. I have never had to try to drill one out ultimately to try to use an ez out, plus obviously on a crankshaft you really don't want to take any risk on something like that.

BTW, there are some other one off Audi bolts with unusual head (tip) patterns I have found in internal motor work like the stretch cylinder head bolts on a 4.2 (and probably other motors now), so probably good to check manual and tool specialty places if not obvious they are trisquare (or Torx). If it is a specialty tool, you can find them through catalogs and Baum Tools and such, but often sites like ecstuning or even Ebay have them once you know what you are after.

hunterp27

Quick update on project "oil leak fix"

1. stripped bolts were extracted successfully
2. upper oil pan has been removed
3. all parts needed have been ordered (bolts, belt, connectors etc....)
4. mating surfaces being cleaned and other clean up being done while waiting on parts

After learning the engine had been removed once before, i went back to the maintenance and service records for my car and learned that the following things were done:
current mileage 73, 654
63,763 miles - new Audi battery
- full carbon buildup cleaning service
54,090 miles - intake manifold gaskets replaced
- replaced all 4 upper control arm bushings (nice find)
42,578 miles - carbon buildup cleaning service
- replaced front torque mount
32,008 miles - brake fluid flush
22,094 miles - replaced all 4 upper control arm bushings (seeing a trend here)
11,435 miles - replaced B&O dash tweeter