Gehäufte NW-Schäden bei PD-Motoren? | Posts 16+

Today, I had the opportunity to remove the cylinder head from a T5 BMZ engine. The reason was that four of the exhaust manifold studs were broken (2 were stuck tightly in the head, 2 were easily removable). The camshaft looked like new, despite the engine having 311,000 km on it. The oil was 507,000 km old and low in ash content, as it was originally designed for use with a diesel particulate filter.

However, the manifold had a nice color change (it had gotten very hot, turning slightly bluish).

Hello Bertil,

Quote:

neubaupe wrote the following: I recently saw something in this forum about a "redesign" of the oil circuit in PD (Pre-chamber) engines... This applies to all VW engines... including the gasoline engines that are based on the 827 platform.

Please provide sources for your statements! (This applies to several posts.)
I would like to see a publication from EA188 or EA113 that clearly states that only bypass filtering is used in this system!

Best regards,
Albrecht

Okay, today I took a closer look at the tires of my car, which have 48,100 km on them.

With 4 valves, I observed elliptical patterns in the area of the valve tips (intake valves 1, 2, and 3, exhaust valve 4), with the most pronounced pattern being on cylinder 3, as shown in the attachment. The elliptical patterns on the valve tips are also faintly visible in the left-hand image.
The macro shots make the whole thing look somewhat distorted and more dramatic than it actually is. In order to show what I was trying to capture, I had to experiment quite a bit with a handheld light and the camera angle.

The apparent grooves/scratches in the left image generally run around the entire circumference of all the lobes and, in my opinion, are manufacturing marks. In the area of the tips, the surface of all the lobes tends to appear more highly polished, which is most noticeable in part E3.
With the other camshafts, the manufacturing marks are even more clearly visible around the tip.

If the ellipses are interpreted as eroded micro-layers, then the erosion is greatest in the center of the cam, meaning the wear pattern would not be a laterally rounded tip, but rather a hollowed-out area. Note that the "manufacturing scratches" become less frequent in the direction of the ellipse's center.

According to visual inspection, the lateral bevel is still present at its full width/height everywhere. Therefore, the ridge height adjustment should not be significantly reduced anywhere.

How are the engine specialists interpreting the images?

Hello Ulf,

I'm not a motor expert, but I might be able to identify this type of grinding pattern (I'll call it that for now).
That's also likely because the plungers rotate when they are activated.

When I replaced the hydraulic lifters on my AFN engine (due to occasional ticking).
I found the culprit on cylinder 3. The camshaft looked brand new.
and the hydraulic lifter showed an unusual wear pattern.
It looked like the outer edges of the camshaft had more wear.
as being inside. I could only imagine it happening due to the rotating motion of the plunger.
Sure, here is the translation of the text from German to English:

"Please provide the text you would like me to translate."

If you like, I can send you a picture of the pestle.
I still have it in the closet.

Best regards,

hame22 wrote:

It looked like the camshaft had more wear on the outer edges. as inside.

Were there "wear lines" visible on your NW as well? Then they should have pointed inwards, towards the center of the camshaft, and not outwards like on my NW.

Quote:

If you want, I can send you a picture of the pestle.
I still have it in the closet. } If the shape of the top part differs significantly from the photos above, that would be interesting.

What I find surprising about this design... why the intake camshafts? Shouldn't the camshafts for the PD (presumably referring to some kind of direct injection or similar system) be under more stress?

"Hmm, I'd also be interested to know what the status is regarding the water pump (after 172,000 km) for my engine."

Do you have a plastic valve cover as well? Is there an instruction manual for installation, removal, and resealing? My engine is starting to leak a little, so resealing it might be a good idea.

In addition to the initial and subsequent oil fills (0w-30 LL2), my engine has exclusively used LL3 oil.

Hi Ulf, this can only be caused by either a slight deformation of the cam lobe, specifically at the tip, or by a curvature of the plunger surface. It's possible that the stiffness of the transfer surface is concentrated in the center, and the outer material gives way slightly.
It definitely reminds me of layered knives made by forging. Could it be that the hardened layer was created inductively, and that the hardness varies at different depths, causing these rings to form?
"Definitely, I would be interested in examining the flatness of the Nockenspitze using a ruler and a light source, as there would likely have been a larger gap on the outside of the intact cam."

Benni wrote:

What surprises me about this story... why the intake camshafts? Shouldn't the camshafts for the PDs be under more stress?

Yes, but they use roller rocker arms -> so the PD camshafts don't have any "sliding wear".

Quote:

Hmm, that would also interest me regarding my engine, how the NW (new water pump) is ordered after 172,000 km. Can you briefly tell me if you also have a plastic valve cover

? And is there an instruction manual for installation and removal, as well as for replacing the seal }? Simply remove the top of the timing cover, unscrew all the cover screws, and remove the cover. However, the rubber profile gasket often sticks stubbornly.
It is advisable to remove the EGR unit because the rear edge of the cover often gets stuck on it.

If the seal isn't damaged, it can be reused.
It is recommended to apply a small amount of sealant at the front and rear, where the sealing surface meets the NW bearing cover, as this area is prone to leaks.

Currently, a user on the Mozzforum wrote about their ARL engine and its replacement (also an ARL) and noted that the exhaust camshafts appear to be significantly more prone to wear: in both engines, all eight camshafts are more or less worn down (and the lifters that go with them look similar to the image above), while all the intake camshafts and lifters are still in excellent condition.

Both engines are/were chipped.
This redirects speculation about the cause (or contributing factors) back towards overheated lubricant films on the valve stems, due to heat radiating from the AV valves.
Or is this idea too far-fetched?

It's quite possible that it's a temperature-related issue. After all, 505.01 oils are still being developed and sold.
That also means that 507 00 in 5W-30 doesn't necessarily always completely include the 505.01 specification.
Bitte gib mir den deutschen Text, den du übersetzt haben möchtest.
505.01 is now also available as a 5W-40 C3 oil, and sometimes even has MB229.51 approvals.

Therefore, all the oils are still available on the market.
5W-40 oil, meeting the 505.01 specification, in its original formulation with sulfur. Example: Fuchs TITAN SUPERSYN PLUS 5W-40.
5W-30 oil meeting specifications 505.01 and C3 (Shell and Mobil brands).
5W-40 oil meeting VW specification 505.01 with C3 approval (brands: Castrol and Fuchs).

Not all oil manufacturers (e.g., Shell/Mobil) offer 5W-40 oil with the C3 specification.

Hi,
In the image "Hydros defekt" (Hydros defect), hydraulic lifters with severely damaged surfaces are shown. I had something similar, but less severe, in my 1Z engine.
The mileage was approximately 240,000 km. Of the 8 valve lifters, 6 showed a gray cloud when initially inspected, which upon closer examination revealed tiny craters, barely perceptible to the touch with a hard stylus. I, of course, replaced the valve lifters. The engine oil was always to VW 50500 specification, and I've used Castrol GTX3 for many years.
Next time I change the timing belt, I'll take a closer look at the water pump and the valve lifters.
hg
Herbert.

Last week, at 170,000 km, I had the pump nozzles ultrasonically cleaned at my automotive service center.
I also took a close look at the camshaft. I could not detect any signs of wear.
What I found were traces on the injector nozzle elements, as if something was scraping inside the cylinder head. The traces were located directly beneath the solenoid valve, where it makes contact with the cylinder head.

Hi,

Quote:

Last week, at 170,000 km, I had the pump nozzle elements ultrasonically cleaned at my workshop.

Have you noticed any changes in the engine's performance?

Hello wingmaster!

Quote:

Last week, at my mileage of 170,000 km, I had the pump nozzle elements ultrasonically cleaned at my service center.

Are there any before-and-after photos of the piston domes and camshaft?

Since my vehicle has a similar mileage (180,000 km), I would be interested in knowing more about its condition.
Currently, there's no reason for me to investigate anything, as the engine is running perfectly.

Why did you clean the PD elements?

Thank you and best regards!

Quote:

What I found were traces on the injector nozzle elements, as if something was scraping inside the cylinder head. The traces were located directly under the solenoid valve, where it contacts the cylinder head.

Unfortunately, this is normal for two-valve engines. If you are unsure whether the sealing surfaces on the worn edges will seal properly again, you can deburr the areas with 600-grit sandpaper. However, be sure to clean them thoroughly afterwards so that no debris enters the combustion chamber.

Ich habe eben festgestellt wieviele Rechtschreibfehler ich in meinen vorherigen Text hatte... Sorry for that. Proofreading...

Ich habe bei meinem ASZ die Pumpe düse Elemente gereinigt weil ich mir für die Werkstatt ein 120W Ultraschallreniger gekauft habe. Reinigungslösung für pumpe düse elemente gibts von vw für 22eur. Ich wollte es erst bei meinem Auto ausprobieren bevor ich Kunden eine reinigung verkaufe. So habe ich selber einen Vorher nachher vergleich. Mein Auto lief vor der reinigung einwandfrei. Nachdem ich die Pumpe Düse elemente raushatte habe ich mir die Düsenspitzen angesehen. Es waren deutliche ablagerungen um die 6 löcher der Düsenspitze zu sehen. Bilder habe ich leider versäumt zu machen. muss man sich vorstellen wie ein ausgebrocher vulkan. Die Ablagerung war mit dem fingernagel nicht zu entfernen. Eine Stunde später bei 70grad sah man die löcher alle wieder schön frei und ohne jegliche verschmutzung. Bei der gelegenheit hab ich direkt alle PDE neu abgedichtet und dem ASZ einen neuen Kabelbaum zu den PDE neue Spannschrauben und neue Schrauben für die Kipphebelwelle Spendiert. PDE natürlich neu in grundeinstellung gebracht usw.. Nach etwa 10 Sek orgeln ist er mit ein bisschen husten angesprungen. Ich bin mir sicher das der Wagen besser zieht. Obenrum ab 3000u/min zieht er defnitiv besser. Ich hatte mir allerdings eher eine Kraftstoffeinsparung erhofft. However, I am currently unable to measure this accurately because it is so cold that my auxiliary heater is running constantly for the 20km commute to work, whether I want it to or not.
The sealing sets for the PDE are unfortunately quite expensive, but I still think it was worth it. Now I know that the PDE won't burn a hole in the piston anymore due to a bad spray pattern.