2007 B5254t2 TB running 1mm over inside edge of cam gear

[cn90]

Well,

Maybe @vtl wants to chime in:
- What brand of serp belt @vtl used?
- How many miles on the serp belt when it happened?
- Associated pulleys (PS Pump, Alt, Idler, Ac compressor pulleys)...any issues.

It is easy to blame the belt but a thorough analysis may point to the root cause.

Anyway, I will continue to use Conti TB and serp belt and change them out every 110K miles...
-

[cn90]

Also,

The serp belt tensioning system...
- The tensioner rotates along its axis. I spray some silicone lube in there once every few years. This allows the arm to pivot smoothly.
- The pulley itself: I replace every 110K.

Then at ~ 200K+, replace the entire assembly (tensioner + pulley).

[jonesg]

Well,

Maybe @vtl wants to chime in:
- What brand of serp belt @vtl used?
- How many miles on the serp belt when it happened?
- Associated pulleys (PS Pump, Alt, Idler, Ac compressor pulleys)...any issues.

It is easy to blame the belt but a thorough analysis may point to the root cause.

Anyway, I will continue to use Conti TB and serp belt and change them out every 110K miles...
-

I shredded a serp belt, because the tensioner pulley let go, the bearing was gone.

The serp belt getting into the timing belt is common on diesels .

[jonesg]

I guess I did not wan't to believe it but I have to, have always figured Gates as a quality brand (and it was sold to me as oem-quality). Changed to a INA kit, belt is branded INA made in italy. Now the belt runs right in the middle. I'm pretty sure the culprit is the Gates branded tensioner which is not running straight, visible to the naked eye when you have it off next to the INA tensioner. Gates belt is probably fine as well as the idler. I did leave the Gates WP in there, for now atleast. I also put a Contitech aux belt but oh well, seems you can't win here. And yea, next time I'm doing my hours of research _before_ I buy anything for this car. I'm used to 740s, could use a fucking shoelace as a TB on those...

changing the timing belt on my old 740 was ...Get a knife, cut the old belt off, slip the new belt in place, release the tensioner.

[Schokakola]

Well, I guess I'm changing the WP after all since I bought it as a kit and the parts store said I have to bring the whole kit back if i want my money back. Good thing is that they agreed that the tensioner is bad. Brought the INA tensioner that was originally on the car with me to show that the Gates one isn't straight. This time around the WP will come in a blue box. Hope they refund me some coolant too...

[cn90]

WP: Aisin is the factory brand (Volvo Blue box is Aisin). Hepu is good too.

Belts: Conti is fine.

Tensioner: INA is factory...