2,5TDI: Teile in der Ölwanne | Posts 16+

Ruffy wrote:

Are the working clearances of the hydros very small? I mean, the wear on the shafts is only a matter of millimeters. I estimate that driving becomes impossible at around 2mm.

Then some of the slide rails may already have worn down by 5mm.

Ruffy wrote:

What do you mean by that? If they are broken or something?

If some are not filled with oil immediately after being started.

Enjoy your meal! / Have a good lunch! I also wanted to report here how things turned out in the end:

So, I spent the weekend back home and I finally looked into the matter. It turned out that the count of parts in the oil pan was correct, and 3 rocker arms had fallen out.
The assessment provided by Tagessuppe was, in fact, quite accurate. They practically dissolve into thin air!
The reason for the jamming isn't just the initial settling-in period, but also how the drawbars settle in. First, a photo of the eliminated contestants:
" color="red">Bitte keine Links zu externen Dateihostern! a) nerven die zusätzlich notwendigen Klicks, b) Wartezeit, Werbebanner/Werbepopups und notwendige Registrierungen, c) ist nach einiger Zeit die Datei weg und das Thema für andere Leser nutzlos!

Bitte nutze 'Attachment hinzufügen' bzw. das Upload Forum hier.

Thank you for the photos!

The differently colored lever is therefore a new one, presumably with a different hardening process.

m;

Good evening...

Yes, I uploaded the pictures before, because I don't think there's anything like that in this forum, and I was always interested in seeing what kind of damage actually looks like.


"The 'Andersfarbige' is, as you correctly pointed out, the differently hardened lever. Otherwise, there were absolutely no changes to this component. I would have liked it if the contact surface for the camshaft had been increased." But tool changes are usually not well received...


Best regards, Marcus.

My levers didn't look that bad back then. Was that an accessory item?
"On my unit, some of the cams were okay, others were worn, and others had pitting." Where there were pits, the clay was also soft.

Hi everyone!

Okay, so the three items in the photos are the ones that fell off due to the gradual wear and tear that eventually led to them detaching. The other 21 looked the same in terms of wear depth.

All the levers appear to be original, as the camshafts are also still the original Audi shafts. Furthermore, they all look exactly the same and have the same level of hardening. Don't assume that any accessories were installed here.

"On my engine, all the camshaft lobes have been worn down by the same amount, in the range of 0.3-0.5mm. One lobe looked better than the others, where a lifter was already missing. I haven't checked for any correlation between pitting and lifters. However, I also haven't found any lifters that were defective." However, I still replaced the three units with the missing levers for safety reasons.

How many miles were on your engine back then?


Best regards, Marcus.

Purely out of curiosity:

How well does the 2.5 actually run, if it's thrown the connecting rods out? Normally, it should then have the running characteristics of a bag of nuts...

Octavia_4x4 wrote:

Normally, it should then have the running culture of a bag of nuts...

No, you usually don't notice it at all.

Yep, I can confirm that! So, even though three valves weren't being actuated at all in my case, I didn't notice it. I only realized it was due to the parts in the oil pan.
There was a slight misfire at idle, but that was all. That's gone now. In terms of performance and, especially, fuel consumption, it hasn't made much of a difference. Perhaps you can tell by the top speed, but I actually never drive that fast.

Best regards, Marcus.

Mine had approximately 160,000 kilometers on the odometer.

Next to me was a first-generation A6, also with a 2.5 TDI engine, and it was making a clicking noise so loud I thought everything was going to fly apart... probably the same problem, clicking, rattling, clattering... it was awful.

"In that case, the hydraulic tappets are definitely going to fail! Mine never made any strange noises... I think you need to act quickly if you hear a clicking sound, because then the valve lifters will come loose even faster. And they don't always fall out cheaply, like they did for me... it can quickly lead to a complete "mess"."


Best regards, Marcus.

I'm just wondering one thing... if the valve lifter is removed, then, as far as I understand, the affected valve will no longer be actuated - how can the engine still run? Or am I mistaken?

Octavia_4x4 wrote:

How is the engine supposed to run in that situation? Or am I missing something?

All V6 TDI engines are 24-valve. A valve won't do anything.

TDI-GTI-4-Motion wrote:

Octavia_4x4 wrote: How is the engine supposed to run in that situation? Or am I missing something? All V6 TDI engines are 24-valve. A valve doesn't do anything.

That's exactly what it looks like. "In my case, three intake valves were disabled on different cylinders, and it doesn't seem to make much of a difference..."

And that, of course, raises the question for me: Why even build this engine with a 4-valve design when there was already a severe lack of space and it had to compromise durability? An engine with a 2-valve design and correspondingly larger valves would have been sufficient as well. Especially since the power loss due to halving the number of valves being actuated in this area would have almost halved... after all, even with the 4-cylinder engines, 150 horsepower was possible with a 1.9-liter displacement... with a 2-valve design...


Best regards, Marcus.

Ruffy wrote:

And that, of course, raises the question for me: Why was this engine even built with 4-valve technology...?

Otherwise, you would never achieve such a beautiful torque curve.