Is a slight squeaking sound from the VTG adjustment normal?

Hello everyone!

Since I haven't had much opportunity to gain experience with VTG turbos yet, I would like to direct my question to the experienced "tinkerers" here.
This week, I checked the ease of adjustment of the VTG (Variable Turbine Geometry) on my beautiful GT1749V turbocharger, which I plan to install on my EGR (Exhaust Gas Recirculation) engine that currently uses a wastegate turbo.
I obtained a 100ml syringe and connected it to the membrane dosing unit of the charger using a short piece of tubing. The adjustment mechanism can be moved smoothly and virtually without any noticeable backlash across its entire range. So far, so good.
However, what's noticeable is a metallic squeaking sound, which makes me a little suspicious. Is it normal for the VTG mechanism to produce such metallic squeaking noises, or is this a sign of impending stiffness or difficulty in operation?

Thank you for sharing your experiences.

Regards,
Alex.

Hello.

The entire mechanism, including the levers, guide vanes, adjusting ring, and linkages inside the container, is not lubricated, so "metal rubs against metal."
As long as everything works perfectly and smoothly, in my opinion, it doesn't really matter.

Hi!

Hello.

The entire mechanism, including the levers, guide vanes, adjusting ring, and linkages inside the container, is not lubricated, so 'metal rubs against metal.'
As long as everything works perfectly and smoothly, in my opinion, it doesn't really matter.

Hi!

hello donalexo,

I heard a squeaking sound from my VTG adjustment during the second-to-last test spray, and this time it groaned like a door in a haunted house (though more quietly).

However, my VTG (Variable Turbine Geometry) is definitely stiff, especially in the last quarter of its adjustment range, near the limit towards maximum boost pressure.

I can't describe it any better than that.

Best regards.
herwig

R.M. wrote:

The entire mechanism, including the levers, guide vanes, adjusting ring, and linkages inside the container, is not lubricated, so "metal rubs against metal." As long as everything works perfectly and smoothly,

in my opinion, it doesn't mean anything.
That also corresponds to my experience.

Sure.
Even my new loader in the AXR is making those noises. Absolutely no reason to worry.

Hello everyone!

I have a habit of always trying to get to the bottom of things. Today, with the nice weather, I quickly disassembled my VTG turbocharger on the balcony and cleaned the VTG mechanism.
Actually, the adjustment mechanism was already easy to adjust before, but now, after cleaning, there is almost no noticeable resistance when adjusting it .

Here are some pictures for those who are interested.

Regards,
Alex.

Hello donalexo,

How did you get that thing so clean (with a wire brush, a toothbrush with alcohol, or by soaking it in biodiesel)?
As soon as my pressure cooker finishes cooking, I'll be enjoying the results too. It would have been interesting to see a photo of your hands .
Are the screws for the lid available as spare parts (ET) from VAG? I think you should definitely use new ones, right?

Hello.

I used an old toothbrush and rubbing alcohol back then, and I didn't soak the thing beforehand.
To my knowledge, these screws are only available from VW, but you can get them if you order the entire charger .
So, I reused the old screws, and the loader wasn't old either. If they're already two sizes smaller, you can also get some of medium hardness from the hardware store; I don't think they're exposed to any special stresses.

...donalexo might have a completely different perspective on that...

Best regards,

@ oldewurtel:
I completely cleaned the charger without using any cleaning agents like brake cleaner, alcohol, diesel, or other substances.
For the mechanical cleaning process, I used an old toothbrush. I carefully removed any large crusts with the edge of a screwdriver.

@ R.M.:
I reused the same screws. Besides their static preload, the screws are practically subjected to very few operational forces. The condition of the screws was okay, so I simply reinstalled them.

Regards,
Alex.

I believe the screws are made of some kind of specially heat-resistant steel. Ultimately, the bolts and nuts used to attach the exhaust system aren't made of ordinary steel; they're a very expensive, high-temperature-resistant material (around 20 euros for a handful of bolts and nuts).
Have you ever seen a turbocharger housing glow, preferably at night or in the twilight? It turns a bright red, it's quite eerie! I can't imagine that a regular screw would maintain its tension in that situation.
If you need screws like that, there are ATL overhaul and repair companies, such as TurboTwins in Schwechat, near Vienna. One would expect to receive something like that.

Have you ever seen a turbocharger housing glow, preferably at night or in the twilight? It turns a bright red, it's quite eerie! I can't imagine that a regular screw would maintain its tension in that situation.


Sure... it even works during the day!

[img][/img]http://www.ralfhandel.de/images/turbolader.jpg{MARKER}

Hi,

I don't want to overshadow Alex's work, but I'd like to add a few more pictures here to make this thread something like a VTG picture book (so that when I open it up, I know what to expect).

http://www.technologie-entwicklung.de/Gasturbines/VNT15-Turbo/vnt15-turbo.html

m;

I don't want to overshadow Alex's work, but I'd like to add a few more pictures here so that this thread becomes something like a VTG picture book.

Hm, why? Then nobody would use the search function anymore...

Okay, go ahead.

because with "VTG Bilderbuch," you can now find exactly this thread .

SCNR
m;