Timing Belt Parts for 2000 AMF

Hello everyone,

I want to finally resolve the timing belt issue (60,000 km interval) on my Lupo 1.4 TDI (AMF). My 2000 model still has the shorter interval, but from the 2001 model year onwards, it's 90,000 km. Unfortunately, VW is being unhelpful and refusing to provide information ("we are processing your request"), and the workshop only knows for sure that the new parts fit on the 1.9 models.
According to AKTE, the timing belt is identical for the 2000 models and newer versions; only the shock absorber and tensioner have different part numbers.
Most likely, the new parts will fit without any problems, as they probably won't significantly change the engine block or its mounting brackets.
Does anyone know more about that?

Thank you, because my timing belt is overdue again, and I don't want to install that 60,000-mile part again.

Thank you.

Olaf.

P.S.
To clarify: I don't need any information about supposed VW approvals, because those don't exist anyway; I just want to know if the parts are COMPATIBLE.

Hello,

Check if the timing belt sprocket on the crankshaft is still the same.
To my knowledge, there was also an attempt to solve the lifespan problem by modifying the tooth profile on the timing belt pulley.

Best regards, Rainer.

Rainer K. wrote:

... To my knowledge, there was also once an attempt to solve the lifespan problem by modifying the tooth profile on the timing belt pulley...

This is not an attempt, but a fact.
By using a variable tooth engagement on the crankshaft pulley, the aim is to prevent the timing belt from slipping off the gear at the moment of relaxation (after the PD boost phase), which would otherwise lead to faster wear.
This is the most important change in the gear-reduction drive of the PD motors.

@Bertil:
Just out of curiosity: Could you explain the 'variable tooth division on the crankshaft pulley' a bit more, or do you have a link to some information about it? I can't imagine what that means at all.

Hello, I'll try to explain it:
The crankshaft pulley has altered teeth in two locations (slightly longer, and I believe the angles are also slightly different). The changes are precisely at the points where a cam lobe pushes on a timing belt element (the load on the timing belt is a staggering 400 Nm).
The modification aims to prevent increased wear and tear. Consequently, for example, the AJM engine can achieve a maintenance interval of 120,000 km starting from the model year 2004.

PrivatBereich wrote:

Just out of curiosity: Could you explain the "variable tooth division on the crankshaft wheel" a bit more, or do you have a corresponding link? I can't really imagine what that means.

... you ask questions ...

Okay, I'll give it a try:

Due to the pressure forces generated by the positive displacement elements, an elongation occurs on the trailing flank of the gear. This can cause the teeth of the gear to impact against the flank of the tooth that is currently disengaging. A larger backlash prevents this from happening.

'Excellent work, Bertil; I doubt it could be presented any better.'

Okay, I'll check the AKTE system sometime soon...
Can the sprocket be replaced relatively easily (or how is it attached)?

Regards,

Olaf.

You can easily unscrew the crankshaft pulley by removing the 19mm hex bolt, using a suitable holder to prevent it from rotating. (The bolt is quite tight, as it's tightened to 120 Nm plus an additional 90 degrees.)

Does the crankshaft pulley have the same VW part number for both models?
What does that tell us?

Regards,

Olaf.

@Bertil:
Thank you for the excellent explanation with the picture; now I can really understand it well. It's actually very logical, but still somehow clever...

@Olaf:
This definitely means that in the case of a replacement, only the new crankshaft sprocket with variable timing should be used.

I would like to check if the same part number is actually printed on your crankshaft pulley. This hasn't been clarified by checking the records (AKTE).

Regards,
Private.

"However, I would like to check if the same part number is actually printed on your crankshaft pulley. This hasn't been clarified by checking the records (AKTE)."

Great... and how can I find that out without having to order the part? The person at VW said, of course, that if the part number is the same, it would also be installed in the 2000 model if you were to replace it. However, the timing belt interval wouldn't change.
Do you have any reliable sources that specify which PD motors had the modifications to the crankshaft gear implemented as you described?

Regards,

Olaf.

Hi,

Not only the pulley wheels, but also the flanks of the belt itself can be modified. According to Contitech, there are many variations, sometimes even for use on the same pulley wheels. According to ContiTech News 01/04, ALL of the profiles shown below are used on the same wheels...

Is the old/new belt truly completely identical?

According to the VW part number, it should be..., but unfortunately, I can't physically examine the part.
I strongly suspect that it's not him... but even so, it would probably be installed by VW. However, if that were the only issue, they could simply give a 90,000 km service interval like they did with the 1.9 engine in the Golf IV, which they didn't do?!

Regards,

Olaf.

For the sake of completeness: I've now conceded and acquired the parts from the 2000s (I would have to buy the 2001 shock absorber blindly, and that experiment is too expensive for me at over €80). Furthermore, I discovered that starting in 2002, the tensioner pulley was changed again, which completely eliminated the need for the separate shock absorber.
Ob und wie das alles paßt, ist die Frage. Fakt ist, daß es schon beim 2000er 4 "Versionen" mit unterschiedlichen Befestigungen der Spannrolle bzw. unterschiedl. Sprovides a tensioning roller.
Let's see if Volkswagen will comment on this topic again at some point.

Regards,

Olaf.

P.S.
VW has commented.
Ref. No.: VW-2004/01-068045
Dear Mr. Goetz,
Thank you for your inquiry.
Please understand that we cannot provide you with a technical answer to your question.
We are unable to respond to your request. The modification you requested is not something we can provide.
It has not been carried out. Therefore, we have no data available on this matter.
In addition, this extends the interval for replacing the timing belt.
it has been achieved that the position of the tensioner on the motor has been changed.
became. Such a modification is not possible retroactively.
For any further questions or suggestions, please do not hesitate to contact us at any time.
Order.

Sincerely,

cc: Bernd Schmitter cc: Katja Schott