AKN Timing: Schedules & Information

Hello,
Is it sufficient to check the valve timing on the AKN engine by simply inserting the crankshaft locking tool, the locking pin into the injection pump rotor, and the two locking tools into the camshafts at the rear?

How precisely must the camshafts be aligned with the rest of the timing system, considering a rough engine running noise or a knocking combustion noise?

The tools are sufficient to adjust the valve timing on the engine.
If the engine is running roughly, I would check the fuel injection timing using a VAG-COM device and possibly correct it.

"Start of injection dynamically measured using a Bosch KTS 520 in low-load conditions."

Late: Should/Is, 0-4°/ 2°.
Early: Should be/ Is, 14-17°/ 14.8°

It should actually fit...

Yes, the values are good. Why do you think the engine is running roughly? Was it different before?
Basically, a V6 engine runs very roughly. It almost sounds like it's misfiring.
Do you notice anything else, for example, a lack of power?

We have several AKN units among our customers, and they all run quieter and with better performance characteristics, even though almost all of them are chip-tuned.
I'm going to double-check the valve timing (after the timing belt replacement), and the mass airflow sensor has already been replaced.
If it then runs normally, I will do the next timing belt replacement, including the camshaft holder brackets at the back of the head .

Hi Autofitti,

If it then runs normally, I will do the next timing belt replacement, including the camshaft holder brackets at the back of the head .

That's better!

Timing set with camshaft locking tools and it's good!

So, is it working better now?

Is it good that the engine doesn't make that rattling noise anymore?
If that's the case, then it's clear that the valve timing is very important, as are the specifications for the camshafts. That's what I thought.
What likely happens if the valves open too late or close too early, or vice versa?
Especially with a motor like that, meticulous adjustment is probably essential.
Please provide the text you would like me to translate from German to English.

Okay, so I had the two valve cover gaskets at the bottom of the cylinder heads, I inserted the dowel pin into the block and engaged the crankshaft, and I locked the fuel injection pump. The fuel injection pump and crankshaft were aligned correctly – the two camshafts were probably about half a tooth too early (measured at the edge at the back of the cylinder head, approximately 2-3 mm).
After that, I unscrewed the dowel pin from the crankshaft, removed the belt from the injection pump, rotated the engine in the direction of rotation until the camshafts were aligned, then loosened the camshaft gears, set the crankshaft to top dead center (TDC), and then tightened the camshaft gears again. I put the belt back on the injection pump, adjusted the tension, and loosened the timing wheel for the injection pump belt, centering it.
The engine was revved twice to reach the correct temperature - this worked. Then, the fuel injection timing was adjusted to 1.8° before top dead center (BTDC).
The engine ran better than ever after the correct adjustments, and the power delivery during acceleration was excellent again. I assume that poor cylinder filling was the reason for the miserable power delivery.

Now, it's running almost as quietly as my VR6 .

At the friendly workshop where I got the tools, I was told that some mechanics don't block the camshafts because of the extra effort involved and the risk that the vacuum pump or the sealing cover on the right side might not seal properly.

Instead of doing it the usual way, they mark each camshaft wheel with a paint pen before disassembly. They loosen the screws and make 4 marks on each wheel: 2 on the inner side, opposite the cone, and 2 on the outer side, near the timing belt cover. Then, they remove the pulleys and re-install the timing belt with the camshaft wheels. This is supposedly better because you have to worry less about the belt routing around the crankshaft, tensioner, and idler pulley on one side. However, I can imagine that it might be quite fiddly to align the pulleys and the timing belt.

Next time I'm working on a V6 TDI, I'm going to try something out to see what makes more sense. I've already built the tools to lock the camshaft and crankshaft – it shouldn't be a problem if you have a lathe. I still have the dimensions.

So, the diesel engine seems to be very particular about the timing, and I'm no longer interested in knowing what would happen if the timing was off by a whole tooth...

The gasoline engines aren't overly sensitive; the V6 2.4L, V8 3.7L, and S6 V8 4.2L engines have run wonderfully after the timing belt replacement without any issues like the camshaft gears getting locked (they were simply marked). The principle of "if it ran before, it should work again afterward" tends to apply here.

Happy creating!

'Next time I work on a V6 TDI, I'm going to try something to see what makes more sense. I've already built the tools to lock the camshaft and crankshaft – it shouldn't be a problem if you have a lathe. I still have the dimensions.'


Hello Autofitti, I'm interested in the dimensions/drawing... I'm having the same problem with the loud engine noise, which sounds like knocking. All the other V6 engines sound different...

Best regards,
René

Next time I'm working on a V6 TDI, I'm going to try something out to see what makes more sense. I've already built the tools to lock the camshaft and crankshaft – it shouldn't be a problem if you have a lathe. I still have the dimensions.


Hello Autofitti, I'm interested in the dimensions/drawing... I'm having the same problem with the loud engine noise, which sounds like knocking. All the other V6 engines sound different...

Best regards,
René

"If there's interest and several people want a drawing of the tool, I'll sit down and create a proper drawing. If the price for the tools wasn't so high, I would have bought them. I would then scan the drawing and ask Mr. Kaufmann to post it here."

Hello Autofitti,

I would really appreciate it if you could provide drawings or sketches of the necessary tools.

My interests, in order of priority, are:
(In the repair manual, the corresponding VAG number is listed next to each component name.)

Pos. _ Description

1 ___ Camshaft locking devices 3458
2 ___ Fixing screw 3242 (for securing the control unit).
3 ___ Counterhold 3036 (for holding in place while loosening/tightening the end cap screw of the...)
_____ camshaft gear)
4 ___ Locking pin 3359 (for securing the injection pump rotor)
5 ___ Positioning pin 40011 (for securing the hydraulic tensioning element of the timing belt).
6 ___ Setting pin 10060 (for securing the spring-loaded clamping element).
_____ V-ribbed belt)

For items 4 to 6, it may sometimes be sufficient to only provide the diameter and length. This is just an assumption, as I am not familiar with the tools.

Okay, I understand. Please provide the German text you would like me to translate into English. I will provide only the translation.

In the near future, I would like to replace the serpentine belt and timing belt on my vehicle (A4 Avant, manufactured in December 1999; engine code AKN) myself, and I would like to acquire the aforementioned tools beforehand so that I don't have to worry about them at the time of the repair.