Crankshaft journal surface no longer flat = engine damage??

Hello everyone,
'Because my car, an Audi 100 Avant 2.5 TDI from 1992, was making an undefined squeaking noise, I took it to my trusted mechanic. They discovered that the lower pulley had become loose and was wobbling. After replacing the entire belt drive system, they found that the contact surface on the crankshaft had been damaged by the old pulley and was no longer perfectly flat. Now, the new pulley is also wobbling, although not as much as the old one. The mechanic told me that I would need a new engine block because there is no tool to machine the contact surface to make it flat. This tool is only available for the 1.9 TDI engine.' The reason is likely that otherwise the pulley would be too close to the oil pump, and then it would rub.
Could you give me some advice on whether there are any cheaper alternatives to a new engine block for me? In the two Audi forums that can be accessed through typc4.de, it was suggested that the worn-out material be replaced with liquid metal. Can this work, and more importantly: Will it last?

Mathias

Hello,

How about a new crankshaft (approximately 850 EUR)?
For a 1992 model, it might be a good idea to replace the crankshaft bearings and connecting rod bearings at the same time.

'That's another idea. Can the crankshaft be removed from a C4 without removing the engine?' I hope so, because otherwise I would essentially have to get the entire engine overhauled with new piston rings, etc., right?

Hello,

To access the crankshaft, the transmission needs to be removed (the clutch can be inspected at the same time).
To remove the oil pan, it may be necessary to loosen an engine mount to slightly raise the engine. You don't have to completely disassemble it.
Tip: These tasks should really only be performed by someone who knows exactly what they are doing (which actually excludes many workshops, or ).

Well... I called two engine repair specialists nearby. Both believe that either material needs to be welded onto the old shaft or a new one needs to be installed. The cost is around 1K. I think this is the most sensible option, especially since I plan to drive the car for a while longer. The maintenance personnel should already know how to properly remove the shaft and install a new one.
First of all, thank you for your help with the decision-making process.

..And I switched to a diesel engine to save money.. Well, you know, things like that happen...

Hello,

As far as I can tell, your engine is a 5-cylinder TDI.
If that's the case, then I can tell you about the experience a colleague of mine had with this engine.
Act 1:
After approximately 50,000 km, the crankshaft developed a leak. A new seal was installed, but after 10,000 km, it leaked again. It was then discovered that the front bearing housing of the crankshaft was worn out. Engine scrap -- first replacement engine...
Act 2:
After another 30,000 km, the same problem as with your engine occurred -- a new crankshaft, free of charge!
Act 3.
After another 25,000 km, the shaft seal was leaking again!!! See Act 1 -- second replacement engine...

Sure, here's the translation:

"Side note:"
A motor repair technician once mentioned something about "...the crankshaft vibrations in the 5-cylinder engine." TDI engines increase the engine's...

Act 4:
The engine has been running flawlessly for 80,000 km! However, the timing belt needed to be replaced... but the engine didn't survive that. This is the third engine failure, and the workshop is covering the cost.

Is everything going better now with the third attempt?


Regarding your problem: there is now a procedure to repair the KW stubs, but I can't tell you whether it will be a long-term solution. I'm more inclined to believe that your engine has a pre-existing condition.

Best regards,
Bertil