Serpentine Belt Tensioner Broken / Flywheel Damaged 2.5TDI

Hello everyone, yesterday I had to deal with a squealing noise and a belt smell (2.5 TDI, year 1999, 132 kW, 205,000 km). I took a closer look at it, and after disassembling the entire front (I had to cut through the bumper bracket with a handsaw because the stupid nut or this damn metal piece broke off, but I managed to put it back together ), I removed the radiator. When I had the radiator out, I saw that the idler pulley was broken, the crankshaft pulley was damaged, and everything around it was a bit worn, probably because the bushing in the idler pulley bracket is worn out. Has anyone else experienced this before?

Hello,

Yes, I know.

The tensioner roller is so worn that the belt comes off, which can cause significant damage. There is a repair kit for the worn roller pin (approx. 20€). However, it's quite difficult to access and repair. If the roller is severely worn, you need to replace the entire aluminum bracket (approx. 150€) along with the pin, because otherwise the new pin will also become loose and the problem will recur.

When transferring ownership, you must:

Remove the A/C compressor (disconnect it but leave it connected!).
Air conditioning compressor bracket is missing.
Power steering pump removal.
Remove the oil cooler.

Then you will have access to the belt tension adjuster. This is attached to the block with 4 screws.


If you only need to replace the pin where the clamp is attached with the Torx screw (i.e., using a repair kit), you only need to remove the clamp and then access the rear hex screw (hidden behind the damper and in a tight space) and loosen it. Then you can simply pull the pin forward out of its guide.

I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.

To be able to loosen the bolt after it's been installed, you'll probably need a welding machine. Otherwise, there's nothing to hold it against.

Thanks for the tips. Yes, I managed to fix it, but now I'm missing the bracket where the tensioner is attached! I think the bolt simply broke off because it was worn out. By the way, I managed to get the bracket and the bolt without having to remove the oil cooler or the power steering unit!

Hi,

Did you use the REP set? I mean, the two plastic bushings, the bolt, and that strange washer that's located right behind the hex screw? The tensioner itself is attached to the bolt with a Torx screw.

Yes, I replaced everything. Otherwise, the screw would have broken off again soon because the bushings were completely worn out. There was also a huge amount of rust inside! I only regretted later that I had removed the servo pump and the entire bracket, which would have saved me a lot of work, because it's also possible to do it without removing the bracket! You just need a welding machine. Well, now everything is new. I also replaced all the pulleys, etc., and I slightly modified my pulley with a file; it should fit. But thanks for the tips! Yesterday evening at 10:00 PM, it was running again, which is great because I don't have to go to work by bike anymore!

How did you replace that socket using a welding device?
I would also like to replace this socket without having to disassemble half of the engine.

Okay, now that I think about it, it makes sense! You simply unscrew the bracket at the front using the Torx screw (which broke off in my case). Then, you grab a welding machine and weld something onto the bolt (where the Torx screw goes). Ideally, weld on an 8mm nut, so you have something to hold onto while you unscrew the 8mm bolt from the back. Then, knock out the old bushings, and maneuver one of them from the back into the hole. Use the 8mm bolt and a few washers to tighten it in place from the front, then just push the other one in from the front, and you're done!