Oil in timing chain drive - MKB ABS (Solved)

Hello,

Our Vento, which is now 21 years old, surprisingly passed the technical inspection (TÜV) again. Therefore, I now "have to" make sure that he has had oil in the timing belt system for some time.

During an initial inspection, the situation seemed straightforward. The valve cover, located on the rear of the engine on the timing chain side, was loose. There was also a noticeable amount of oil leaking down the engine block from that area. Okay, so I replaced the valve cover gasket, cleaned the timing belt system, replaced the timing belt, and... changed the oil in the timing belt system.
It quickly became clear that the oil seal for the camshaft was also damaged. It was rotating with the shaft and could be easily moved back and forth on it. I replaced that one too, and... there's oil in the belt drive again.

I first pressed the new oil seal in using a large 36mm socket, and then a bit further using a 32mm socket - first by hand, then with a few gentle hammer taps. Visually, the seal is perfectly in place. The inner lip is in contact with the camshaft and is not deformed. However, the sealing ring is still letting oil through.
What could possibly go wrong during assembly? Do you absolutely need the original set of retraction sleeves?

Bye.
peace

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What could possibly go wrong during the assembly? Do you absolutely need the original pull-tab set?

Is the front NW bearing stuck? Possibly, the shaft has rotated – in that case, you'll need a sealing ring with an offset lip, or, if possible, a different installation position.

Are you sure the oil is coming from the sealing lip?

I would remove the camshaft, loosen all the bearing housings, remove the front bearing housing, and reassemble everything with a new sealing ring. I would then seal the front ends of the bearing housings with sealant (silicone). The same applies to the VD at the transition between the NW storage area and the ZK.

At this point, you can also see the condition of the NW (presumably a component) and better position the sealing ring. You also don't need any tools, as it can be inserted by hand. It should only be slippery enough so that it can slide into place when attaching the bearing.
If the new sealing ring is made of Teflon, the running surface must not be lubricated.

To replace the sealing ring, you should only need to remove the front NW cover. The NW unit itself can remain in place. The ABS system is essentially installed in the same way as it is in the 1Z model.
hg
Herbert.

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The NW can remain fixed. The ABS system is essentially installed in the same way as it is in the 1Z model.

Purely a precautionary measure.
I have already seen specialists - they made a out of an NW 2.
Adding a few more nuts won't make the mixture too thick. Besides, the sealing ring can be inserted by hand without having to bend the impeller shaft. It's important that the sealing ring can be easily inserted.

Hello,

Autoservice wrote:

Is the front NW bearing seized?

I'll check it out next time.

Autoservice wrote:

then you need a sealing ring with an offset sealing lip

Where can I find one?

Autoservice wrote:

if possible, a different installation position

The shaft seal is approximately 10mm wide and is recessed about 10.5mm into the head - it therefore sits slightly behind the flat surface. If I now install a washer of approximately 1-2mm thickness between the seal and the NW bearing, will this change the position of the sealing lip of the shaft seal? Does that mean the same thing?

Autoservice wrote:

Are you sure the oil is coming from the sealing lip?

Well, as far as I can tell so far. Now that everything is clean, I can see that after a few minutes of engine running, the back of the camshaft pulley is oiled. When the engine is idle for a while, it accumulates on the rear edge of the pulley. No oil is leaking from the outer black part of the sealing ring. The valve cover is also tight. I didn't manage to remove the pulley again yesterday, and when it's installed, you can only partially inspect the inner red sealing lip. But I think it comes out from there, creeps along the camshaft to the timing pulley, and then spreads out due to capillary action and centrifugal force.

Autoservice wrote:

I would remove the VD, loosen all the NW bearings, remove the front NW bearing, and reassemble it with a new sealing ring. I would seal the front ends of the NW bearing with sealant (silicone).

I have Hylomar paste, is that suitable for this? I can't quite imagine what the "front ends of the NW bearing" are, because I haven't seen it disassembled yet. Is that the contact area between the bearing shell and the cylinder head?

Bye.
peace

Edit: Not that I currently need one, but does anyone know if there's a reproduction version or instructions available for the shaft seal puller 2085? It's supposed to cost 90 euros, which is a bit too expensive for my hobby activities.

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Where can I find them?

At Motorenfritze's place. I knew someone who even got parts from VW there. He had figured out the dimensions of the various VW oil seals, but unfortunately, he is now retired.

However, this action is only necessary if the insurance policy is already in effect.

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....By doing this, I am changing the position of the sealing lip of the shaft seal. Does that mean the same thing?

Yes.

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Is that the mounting surface between the bearing shell and the cylinder head?

Yes. Hylomar is also suitable, but please apply it very thinly.

Hello,

Today, I was able to take another look at the issue. On the newly installed oil seal, the spring that presses the sealing lip against the camshaft had popped out of its seat in one location. This was clearly visible after removing the camshaft bearing cover. The camshaft was slightly worn in the area of the sealing lip, but probably not to a harmful extent.
I haven't been able to do a proper test drive yet, but at least during the roughly 10-minute idling with occasional bursts of acceleration, no oil leaked out this time.

Bye.
peace

Hmm, that's a shame - after the test drive of about 30 km, you can unfortunately still see slight oil traces on the camshaft wheel, although this time it's less than after the first failed attempt, and only after a test run.

The groove in the camshaft where the oil seal lip sits is quite shallow. I would estimate it to be around 3/10 of its depth (not measured). Should this really have an effect? In the next attempt, I would use a spacer ring to shift the position of the shaft seal or lip by approximately 1.5mm. After that, it probably makes sense to look for a camshaft from a salvage yard.

I've also encountered a new problem while working on the vehicle. It has very little power. It starts normally and runs smoothly (no misfires, all cylinders firing). I replaced the spark plugs as part of the maintenance. However, I can't reinstall the old ones. The spark plug wire order is correct. I accidentally twisted the intermediate shaft while cleaning the timing belt, but it was marked, and I've since turned it back to the correct position. Is this error pattern typical for a misadjusted ignition timing?

In VCDS, I can only view measuring block 0 for the engine. There are a few values listed there, but unfortunately, none of them are documented.

Bye.
peace

pax wrote:

Hm, that's a shame - after the test drive of about 30km, unfortunately, you can already see slight oil traces on the camshaft wheel again, but this time less than after the first failed attempt, and only during the idle test

.

Maybe my experience can help you.

I also installed a new valve cover gasket on mine.
(You just do that kind of thing when you're already dressed up.)
That was, however, a serious mistake... It resulted in a motor with excessive oil consumption.

The writing simply wasn't well-produced, and the original was just better.
In my case, the oil was leaking out from the right side of the engine, near the transmission housing, but I noticed the loss was actually coming from the upper right side of the engine head. Perhaps it's simply a problem with the left side for you, and you're just constantly thinking it's the Simmering.
I ended up using something like silicone sealant out of frustration, which is a shame, but it probably means I don't need to buy a new seal.

Best regards, Apple.

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I would estimate them to be in the range of 3/10 (not measured). Should that really have an influence? In the next attempt, I would use an intermediate ring to shift the position of the shaft seal or lip seal by approximately 1.5 mm.

"3/10mm would be a lot of wood. I would try to get a sealing ring with an offset lip." If you want to use a spacer ring, you would almost have to glue the sealing ring in place.

Have you checked if the sealing ring currently being used might be misaligned, because - VW has changed the index number behind the part number several times in recent years. In this case, the sealing lip will become contaminated with grime if the nozzle wasn't properly cleaned.

You may have also damaged the sealing ring - the spring doesn't just come off like that.

I would install a new brand-name sealing ring as recommended by the car service and then check again to see if the problem is finally resolved.

Hello!

Yes, so I only get the valve cover gaskets from .
because I've already had problems with cheap, low-quality products.
It's also clear at first glance,
that cheap, imitation products often give a low-quality, shabby impression.
Also, also auch achten Sie darauf, dass der Ventildeckel nicht verbogen ist, falls es sich um einen Blechdeckel handelt.

I've replaced the NW sim-rings quite a few times before, and I've never had any problems with them, which is actually quite surprising... Did you scratch the NW (needle valve)? During expansion?

Okay, let's move on to the timing belt for these engines:
The thing about the intermediate shaft is annoying because you can't really see the markings on it either.

I always mark the timing marks on the crankshaft, camshaft, and intermediate shaft with colored dots beforehand, so that I can later align them precisely to the same teeth again.
If you suspect that something isn't right, a new initial configuration will likely be necessary.
This is a bit tricky, but please tell me first if the engine has a G 28 on the crankshaft. It's been too long since I did something like that on an ABS machine.

Hello,

Apfelsaft wrote:

I also installed a new valve cover gasket on my

.
(You just do that kind of thing when you're already dressed up.)
That was, however, a bad mistake. It resulted in a motor with excessive oil consumption.

Autoservice wrote:

VDD is not the problem at the moment. There is no new oil in the block. The oil is currently only on the camshaft pulley and is already being flung in small amounts onto the timing belt cover.

Have you ever checked if the sealing ring currently being used is possibly misaligned

Steffen G wrote:

? The original ring (which was freely movable on the shaft and in the seat) is in the trash - I need to see if I can find it again. The first new ring was from Reinz. Now, one from Elring is installed. I found both of them in the accessories section using the original part number. By the way, there is no sludge on the camshaft in the area of the sealing ring seat. The popped-out spring during my first assembly attempt was probably my fault. I used a large nut to press the first piece onto the black outer part of the sealing ring. The original tool presses more inwards, on the red area. During assembly, the camshaft was also dry (which is supposed to be the case), but that probably stretched the lip so much that the spring popped off. Since this sealing ring was so deformed after standing around for a week, it was immediately thrown away.

Did you scratch the NW?

Steffen G wrote:

During the disassembly? The first sealing ring could be removed without tools because it rotated completely loosely. It was not fixed either in the outer seat or on the camshaft. There shouldn't be any damage whatsoever to the shaft from the action. If the oil groove on the camshaft is indeed causing a problem in the area of the sealing lip seat, I will replace the camshaft and hope for a resolution to that issue. It will cost me about the same at the junkyard as two crankshaft seals would from the dealership. Unfortunately, I don't have any personal contacts at the parts counter, and I'm afraid that information like details about modified sealing lip seats wouldn't be available to me.

The thing about the intermediate shaft is annoying... I wonder if the engine has a G 28 on the crankshaft... Fortunately, the intermediate shaft was marked with paint. However, large parts of the marking disappeared during my oil removal process for the timing belt drive. But there was still enough left that I'm quite sure I turned the intermediate shaft back to this position. But it's not running properly.
I don't know if the motor has a G28. I can't find any information about that in the documentation. Where would it physically be located?
How would a basic setup work? I've already bought a flash gun. Then I read something about "adjusting the distributor," but I haven't yet identified the specific location where there's something to turn.

Bye.
peace

Quote:

During assembly, the camshaft was also dry (which is supposed to be the case), but it probably stretched the lip so much that the spring popped off. Since this sealing ring was so deformed after standing for a week, it was immediately thrown away.

Since when have FPM (fluorocarbon rubber)/ACM (acrylic rubber) seals been installed dry?

I grease or oil these rings all around. Exception: PTFE. They don't have feathers.

I think the current Simmering is "burnt out" or worn down, like an eraser.

Well, there you have it. I only had the sentence in mind that the seals are made of PTFE and should be installed without any oil or grease. I assumed that the "break-in period" for a 21-year-old car is over, and that only PTFE seals are available on the market now - that's all I know about the subject. It already falls on one's feet .

I will still order the replacement camshaft. Hopefully, this will reduce the risk of another disastrous performance.

Bye.
peace

Hello Pax!

With these engines, adjusting the intermediate shaft and timing belt is really a pain.

As I've mentioned before, I always mark the timing belt and the timing pulleys with colored dots so that the timing belt can be reinstalled in the exact same position as it was before.

The color markings on the intermediate shaft gear for alignment with the engine casing are not precise enough.

I just checked my documents again.
"It's likely that the ABS motor doesn't have a G 28, and the ignition pulse comes from the sensor in the distributor."
Just like it used to be with similar engines.
If the motor has a G 28 sensor, it's located somewhere inside the clutch bell, picks up the signal from the flywheel, and the cable runs up to the starter motor.
I'm not sure, but it's possible that I've confused it with the knock sensor, which the engine should have.



If you have a strobe light, then use it.
Try exploring the ignition timing settings.
Be careful, there might also be a vacuum hose connected to the distribution manifold that needs to be disconnected before taking measurements.

The distributor is rotated by twisting it, and there's a clamping fork located at the bottom of the engine block, which is secured with an 8 mm screw.
If you loosen the screw slightly, you can rotate the distributor a quarter of a turn.
You might be able to use this for... Loosen the intermediate shaft and adjust its alignment.
Take a look at which direction the distributor rotor spins when the engine is started.
I think clockwise.
Okay, please provide the German text you would like me to translate. I will provide only the English translation. Rotating the distributor counter-clockwise advances the ignition timing.

Similarly, the motors are very sensitive to even the slightest misalignment of the timing belt.
If adjusting the ignition timing doesn't work, you should double-check it.