Strong humming from the alternator belt...

Hello dear Diesel enthusiasts - Community ,

I'm new here, but I've been following the discussions in the forum for a while. I'm really impressed that there are so many professionals among us who are willing to help others in need, even when it might be inconvenient for them!!!
I am also quite tech-savvy and have been able to resolve most issues on my own using my own knowledge and skills. However, for this particular problem, I would like to get some suggestions from professionals. Please excuse the length of this text...

Regarding my issue.

I bought a Golf III TDI, 90 PS, manufactured in April 1997, and now it has 126,000 km.

Ever since I bought it, the whirring noise from the alternator's ribbed belt has been annoying me. This noise and vibration are caused by the tensioning element in the range of 1200 to 1500 revolutions per minute. At this speed, you can see that the tension roller is really working and the belt starts to move, which also causes the humming and vibrations.
VW also admits that this design has a major flaw, but what does that even mean to me???
As far as I know, the 1.9 D and 1.9 TD engines, at least in the Golf III, do not have a tensioning element, nor do they exhibit vibrations or rattling noises. This likely causes the alternator's bearings to wear out more quickly. As a result, a tensioning element was installed on TDI engines, which uses a lever and a tension roller to apply constant pressure to the belt. This reduces wear and tear on the equipment, and, more importantly (at least in theory), eliminates the need for maintenance work (such as completely replacing the belts every 15,000 kilometers).
Everything is fine and well, but there is an undamped element that has been installed, which tends to oscillate and rise quickly after being disturbed.
'With models like the Passat and Golf 4, for example, you would additionally install a vibration dampener, or modify the entire construction.' These people don't have any problems, and people like me have to replace the belt and tensioner every 20 kilometers to enjoy smooth engine operation.
I have also replaced them myself once (at 65,000 km), and twice myself (at 90,000 and 115,000 km) (approximately 90 euros each time). I'm getting really fed up and my wallet is empty.

VW admits that it is likely a flawed design, and that there should be an upgrade kit available, but so far they have not installed any!!! Furthermore, they do not specify what components make up this upgrade kit and what it should cost, typical VW-style information...

Now, my thoughts and questions to you:

I would like to have the component with the entire... device removed and replaced with a flat-ribbed belt from a 1.9 TD (6 PK 751) engine. I would then like to adjust the tension using the alternator, as in the good old days. Unfortunately, the alternator and its mounting are not designed for this purpose. Has anyone had experience with this?
Are there perhaps other ways to permanently eliminate this problem?
Can a shock absorber, for example from a VW Transporter, be installed retroactively?

Or could it be due to the incorrectly set injection timing? I've seen a thread in this forum about vibrations up to 2000 RPM due to incorrect fuel injection timing.

Wait for your suggestions and feedback.

Thank you.

Georg-TDI wrote:

Or could it be due to the incorrectly set injection timing? I read a thread in this forum about vibrations up to 2000 RPM due to incorrect injection timing.

If the "Role + Strap" mechanism is oscillating, it's unlikely to be related to the start of the spraying process - at least, this is something completely new for us.

So, focus on the issue related to the design flaw, as the chances of success are quite high (I cannot provide you with specific details).

P.S.:
Can you please post the link to the thread about vibrations up to 2000 RPM due to incorrect injection timing?

[Translating...]

Moin


Wie stark schwingt die Rolle (in cm) - meine hatte mit dem alten Element 1-2 cm gemacht, mit dem neuen fast 0.

ich hab gerade gestern mein Spannelement mal eben ausgebaut (5 min)


Das Spannelement (inzwischen 2 Jahre alt) rastet !! Es bleibt fast in der Luft stehen, wenn man es vom Riemen abhebt und wieder los laesst.

Vielelicht ist das Rasten bei dir noch deutlicher, wodurch der Riemen hart anschlaegt.

Bastelei-Fotos gibts heir:

http://people.freenet.de/golf-schrauber/Spannrolle/Spannrolle_1Z.html

dieselmartin,

die Spannrolle schwingt mit dem neuen Spannelement praktisch gar nicht, aber mit einem ausgeleierten bis zu 2 cm, so wie bei dir auch. Als ich mir selber schon 2 mal ein neues Spannelement bei VW geholt habe, kam als erstes vom VW-Mitarbeiter: „Na, ist ihr Spannelement in einer Stellung eingerastet? Ist schwergängig? Das ist eine typische Make...“.
Allerdings habe ich bei meinen alten Spannelementen solches Rastern nie beobachtet. Hab auch jedes mal das Spiel des Hebels in den Hülsen kontrolliert und gefettet. Mein jetziger ist gerade 1,5 Jahre alt, ist absolut freigängig, aber halt ausgeleiert. Schon nach einem halben Jahr mit jetzigem Spannelement musste ich, um starke Schwingungen zu vermeiden, einen etwas kürzeren Flachrippenriemen einbauen. VW-Leute waren natürlich dagegen und haben mir wegen erhöhter Zugspannung in Kürze einen Lagerschaden der LiMa versprochen. Von wegen eine konstante Zugspannung, schon nach paar Monaten ist die vorgesehene Zugspannung eher weg...
Ging halbes Jahr gut, und schon seit Monaten wieder starkes Brummen und Vibrationen, die auch deutlich im Inneren zu spüren sind.
Da ich Automatik fahre, befinde ich mich öfters im Fenster von 1200 bis 1800 Umdrehungen, besonders im Stadtverkehr, und das nervt gewaltig!!!
Auf der Autobahn fährt man meistens oberhalb dieser Drehzahlen, so dass die Problematik gar nicht auftritt. Die Schaltgetriebefahrer haben da weniger Probleme, sie können sich (im Vergleich zu mir) selber für einen bestimmten Gang und dazugehörige Drehzahl entscheiden.

Danke Euch für eine gute Resonanz auf mein Problem.

Werde mich demnächst mit meiner langjährigen positiver und negativer Erfahrung mit Biodiesel revanchieren. (Hier im Forum habe ich eine Umfrage gesehen)