Questions and notes regarding the timing belt replacement for a VW Passat PD

Dear DIY enthusiasts,

Currently, I am in the process of replacing the timing belt on my new (old ) Passat. So far, I can only say that it's a real pain to do, until you have removed all the plastic parts. But that's another topic.

Before removing the old belt, it was noticeable that the alignment pin for the camshaft sprocket only fit properly when the bolt of the crankshaft locking device had already been rotated approximately 4-5 mm clockwise. Previously, the Contitech belt had been installed with a replacement interval of 120,000 km.

"During the installation of the new timing belt, following various instructions (from forums and Etzold), I encountered the following problems:"

- The pin for the crankshaft upper bearing only fits into its corresponding hole when it is slightly raised from the front.
- When tightening the tensioning roller, it is absolutely necessary to ensure that the nut is open far enough! (In my case, a nut that closed while I was tightening it led to a deformed nose on the Hazet nut spinner ).
- Although the three screws on the camshaft sprocket were widely open during the tensioning process, after tightening the screws of the timing belt drive, the locating pin on the camshaft sprocket could only be removed with great force and the help of a wrench. What could be the reason for this?

Nach mehrmaligem Durchdrehen des Motors (nur im Uhrzeigersinn!) stimmten nach Arretierung der Kurbelwelle auf OT die Markierungen hinter der Nockenwelle überein, allerdings passte der Dorn erst, wenn man die KW wieder ein kleines Stück weiter dreht. Daraufhin habe ich nach den Anleitungen die KW erneut arretiert, die NW-Schrauben gelöst und versucht, die Nockenwelle an der Zentralschraube zu drehen bis der Dorn passt. Allerdings bewegte sich diese keinen mm in irgendeine Richtung (auch wenn die drei Schrauben weit raus schauen). Was habe ich falsch gemacht? Wie problematisch sind beim Pumpe-Düse kleine Abweichungen der Steuerzeiten? During the installation process, the deviations between the alignment pin and the outer tooth (OT) of the timing gear were significantly larger.

Furthermore, the thread on the middle timing belt cover is stripped. Do you have any ideas for solving this problem?

I would also like to mention that the "Etzol" repair manual is very poor for my Passat. The torque specifications for the idler pulley nut (which I tightened with 20 Nm plus 45°, just like the tensioner) and for the water pump screws (which I tightened with 15 Nm) were nowhere to be found. Furthermore, the instructions for removing the crossmember and bumper are very poorly written...
In the forum, some people managed to complete the conversion in 7 hours. So far, I've taken about 9 hours, and I'm currently in the process of installing the ribbed belts.

I thank you in advance for any suggestions.

Schön mal wieder was von dir zu hören ....

haehnlein wrote:

- The pin for the crankshaft upper bearing only fits into its corresponding hole when it is slightly raised from the front.

It happens, but it's not a big deal.

Quote:

- When tightening the tensioning roller, it is absolutely necessary to ensure that the nut is open wide enough! (In my case, a nut that closed while I was tightening it caused the nose of my Hazet nut spinner to become deformed ).

I haven't heard that before.

Quote:

- Although the three screws on the camshaft sprocket were widely open during the tensioning process, after tightening the screws of the timing belt drive, the locating pin on the camshaft sprocket could only be removed with great force and the help of a wrench. What could be the reason for this?

It's also normal and happens in about every other timing belt replacement. That's why it's important to use high-quality tools that can withstand such stress.

Quote:

After following the instructions, I re-secured the crankshaft, loosened the counterweight screws, and tried to rotate the camshaft on the central bolt until the dowel aligned. However, it wouldn't move even a millimeter in any direction (even though the three screws were protruding quite far). What did I do wrong?

The process is agonizing... I'll do it differently.
First, engage the parking brake. Then, loosen the three nuts and slide the driveshaft into the locking mechanism. Tighten the wheel nuts on the parking brake rotor and recheck everything.

Quote:

How problematic are small deviations in the injection timing with common rail systems? During disassembly, the deviations between the alignment pin and top dead center (TDC) of the crankshaft were at least significantly larger.

It's certainly something to watch out for, but if the engine is running smoothly, you have nothing to worry about.
The deviations before the switching point can be explained by the elongation of the timing belt over time.

Quote:

In the forum, some people managed to complete the conversion in 7 hours. So far, I've taken about 9 hours, and I'm currently in the process of installing the ribbed belts.

It's alright... the main thing is that the [machine/device] is working properly again.

I need 4 hours with the transverse engine... And it's much more difficult to handle everything with that setup.

Bertil wrote:

Schön mal wieder was von dir zu hören .... {}

Hi Bertil,

Well, my 1Z engine has held up reliably until today (274,000 km), and the diesel troubleshooting database covers all the common issues of this type .

Bertil wrote:

Das habe ich noch nicht gehört.

It was probably due to the sticky threadlocker that tightened the nut as it was turned clockwise during installation. It was also unusual that the new camshaft screws came from the supplier without any threadlocker applied. The old ones were completely covered in it. In general, thread locker should always be used for these types of screw connections.

I also had the feeling that the tightening torques plus angles for the idler pulley, tensioner pulley, and crankshaft sprocket were close to the material's load limit of the studs or internal hexagon screws.

Bertil wrote:

This is also normal and happens in about every other timing chain replacement. Therefore, it's important to use a high-quality tool that can withstand such stress.

You should never skimp on that, especially when you consider the incredible savings you can achieve by doing it yourself.

Bertil wrote:

So, the procedure is torture... I'll do it differently. First, secure the

NW (Northwest) with a locking mechanism, then loosen the three nuts, and then slide the crankshaft into the locking position. Tighten the 8ONW wheel nuts securely and check everything again.

Bertil wrote:

That is, of course, a very clever and elegant solution! My brain, which was already quite cold, couldn't come up with that at an outside temperature of -3°C

.


}It's certainly critical, but if the engine is running smoothly, you have nothing to worry about.
Die Abweichungen vor dem Wechsel sind durch die Längung des ZR über die Laufzeit zu erklären.}

Running perfectly! Thanks again for the tips.

Hello everyone,

Since when have timing belts been available for different service intervals?

The replacement interval for the timing belt depends on the vehicle type and engine code and number, not on the belt manufacturer or belt type!

A misalignment of 4-5 mm also indicates an imminent failure with a major engine damage!

If you decide to change the belt at such a late stage, it is highly advisable to...
Avoid touching the adjustment screws on the camshaft wheel, because if you do, you'll never get it right again.
finds the starting position!

Since the timing belt is a standardized component, it's necessary to lock one of the shafts.
to replace the belt and adjust the other pulleys by 4-5 mm!

After that, in 98.8% of cases, the tax deadlines will be adjusted accordingly!

However, if I were to block two camshafts, tighten the timing belt, and forcibly remove the blocking tools, then I wouldn't have to worry about engine damage!

Sure, here is the translation of the text from German to English:

'Further explanations can be found below.'

I hope there's something like that here.

greetings hardy disk

Hardy...
What do you mean by "later switch"?
The automatic valve adjustment (AVF) system in question has a fully automatic function, and the regular replacement interval for this motor is 120,000 km.
Apart from that, I don't see anything wrong with the approach taken by the original poster. And Bertil has already mentioned the practical advantages compared to the guide.

Sorry guys,
There's likely a bug in my system, because it's showing 'AVF' as the switching interval.
'Up to 2003: 90,000 km, from 2004 onwards: 120,000 km.'
Now I've looked at the tension rollers and realized that...
The hydraulic system was used until December 2002, while the mechanical system was introduced starting in January 2003.
However, in addition to the two holes, the mechanical component also has a 6mm Allen key socket.
'to apply tension, which is why I assumed it was hydraulic.'

That's why it was a 'late switch.'
'Again, my apologies, Hardy disc.'

Steffen W wrote:

Dieser AVF um den es hier geht hat,bereits die vollautomatische Rolle und das reguläre ZR-Wechselintervall dieses Motors beträgt 120000km.

Hi Steffen,

ich habe nochmal meinen Teilehändler gefragt. Mein Zahnriemen ist von Gates und die Rollen und Wasserpumpe sind von Ruville. Diese haben leider nur ein Wechselintervall von 90.000 km. Mit dem ContiTech-Kit wären es 120.000 gewesen. Da ich Pessimist bin, wird der Riemen sowieso nach 80.000 km gewechselt. Wie erkennt man denn diese "automatische Spannrolle"? Die vorhandenen musste ganz normal wie bei meinem 1Z gespannt werden (einfach bis die Markierungen übereinstimmten). There were no unusual locking or seizing issues here, as described in some cases with other PD engines.

Unfortunately, a few days ago, there was a leak of coolant under my Passat. The first thing you naturally think of is a faulty installation of the water pump on the timing belt . Today, I inflated the cooling system with a bicycle pump (about 1.5 bar -> the pressure valve on the expansion tank opens as it should), and sure enough: the radiator has a leak . Either the service position of the locking bracket damaged it, or VW has only been using inferior quality parts since the 1Z model.

Despite everything, I still have this nagging feeling that all this sensor, alarm sound, button, and display craziness is coming at the expense of the quality of the mechanical components. But that's a different topic...

haehnlein wrote:

Either the service position of the door lock actuator has damaged the part, or Volkswagen has only been using inferior quality components since the 1Z model.

The radiators from the 3B and 3BG models are extremely prone to leaks. I've replaced so many of them already...

Hello Haehnlein,
I just realized that I'll be needing to replace my timing belt soon, and I already have the parts on hand. The picture below shows the old setup for 90,000 km. It includes the tensioner. See also the picture from Pax.
The roller shown in the image from BM is the newer version, also depicted in the upper image. You can see that it no longer includes the belt tensioner. Vehicles equipped with this roller typically have a maintenance interval of 120,000 km. An exception is the Sharan, which has an interval of 90,000 km. For the previous version with the damper, the interval is 90,000 km, and for the Sharan, it's 60,000 km. It doesn't matter whether it's a Conti or Gates belt; the seller likely mixed this up. Both Gates and Conti manufacture ZR belts for original equipment (OE). Also, the Gates 5569XS used here has fabric reinforcement on the back.
There is a third variant where the spindle and bearing of the pulley are different (which may not be immediately obvious visually). However, this version only applies to engines AJM up to motor number 185670 (December 31, 1999), so it's not relevant in this case. All of those had a service interval of 60,000 km.

Quote:

Wie erkennt man denn diese "automatische Spannrolle"?

In this picture, the version with the strap adjuster is shown.

Bye.
peace

EDIT:

Quote:

There is also a third variant where the spanner and the bearing of the pulley are different (visually, not necessarily obvious at first glance). However, this version only applies to engines AJM up to engine number 185670 (December 31, 1999), so it does not apply here. All of them were designed for a lifespan of 60,000 km.

As can be clearly seen in Stefan's picture, the spanner is a replacement part that is commercially available. The manufacturer is NTN.
As far as I can tell (based on what I've seen so far), this is the only manufacturer that is currently or has been used as original equipment. The quality is 100%.
The price is likely up to 40% lower in the open market compared to that of the exploiter. EDIT ENDE



Here is the version with automatic roll function.

hardyscheibe wrote:

is probably a bug in my system, because it shows an "AVF" as the switching interval. "bis 2003: 90.000 km, ab 2004: 120000km".

Hello,

also bei meinem Passat wurde der Zahnriemen zuvor nur einmal bei 120.000 km gewechselt. Bei mir ist die untere Spannrolle des Bildes von Steffen verbaut. Die Art diese zu spannen, ist genauso wie beim 1z. Mein Teilehändler hat mir dennoch mitgeteilt, dass das Wechselintervall des Gates-Riemen mit Ruville-Rollen bei 90.000 liegt. Das Set von Contitech kann auf jeden Fall 120.000 km gefahren werden, da dieses vorher auch verbaut war. Also ist entweder die Auskunft meines Teilehändlers falsch oder es gibt wirklich zwei verschiedene Reparatursätze Auf jeden Fall wechsle ich den Riemen bei 80.000 km. BWith high mileage, I can imagine that the increased clearance in the toothed wheel bearings could also increase the stress on the timing belt.Therefore, an early change is definitely not a bad thing.

Structurally, however, the Gates belt looked similar to the old Contitech belt. When I think about the belts for my 1Z engine, they had significant reinforcement and look much more robust.

pax wrote:

Auf diesem Bild ist die Variante mit Riemenspanner zu sehen.

Hi Pax,

I can't see the arrow and its corresponding marking in this picture. So, is this yet another roller version? On my tensioner pulley, like on the old 1z, there's a marking and an arrow at the base of the roller. When tightening, you simply rotate it until both align, and then the belt is tightened. In Steffen's picture, you can see this alignment on the lower roller in the bottom left corner...

Hi BM,

In your picture, it looks like the new belt has been soaked in G12 . Is that actually no longer a critical issue? I remember that the old blue antifreeze could damage the belts, with corresponding consequences.

Hello,

In the version I illustrated, tension is applied until a 4mm gap (measured in the image using a drill bit) forms, under certain conditions.

Bye.
peace

Quote:

Hi BM, In your picture, it looks like the new belt has been soaked in G12. Is that actually no longer a problem? I remember that the old blue antifreeze could damage the belts, with potentially serious consequences.

No, it was just clear water. The car was parked outside, and it was drizzling a little.

Antifreeze should not come into contact with the belts; if it does, rinse it off with water.