BKC Golf V zweites Mal Zahnriemen defekt innerhalb 2 Jahren | Posts 16+

There has to be some reason for all the fun.
The water pump has already been replaced.
It remains a camshaft that is difficult to turn or that jams.
Individual valves could be the cause if they were either improperly installed (which would cause significant damage) or if they are stuck in the closed position (which would then damage the hydraulic lifters).
Are there any signs of wear or damage on the north-west bearings?
Was the head ever planned? If you don't check the camshaft bore when there's a delay, you might be surprised later.
Were the NW bearing shells swapped?
hg
Herbert.

The cylinder head has never been removed, and the camshaft has never been taken out.
I'll take a look at the camshaft the other day.

Hi there,
At the beginning, you mention that there are stronger ZK screws installed. How did they get in there if not by disassembling the head?
hg
Herbert.

Hello Herbert, one at a time, please.

Jojo81 wrote:

Hello Herbert, one at a time, please.

Why?

They were replaced with stronger ones from the ARL engine, which is not uncommon for performance-enhanced "small" PD engines. They were also tightened correctly during the process. Since then, there has been no coolant loss after full-throttle runs (assuming head lift is not an issue).
But that has nothing to do with the story about the dental rim.

As I mentioned, I suspect the area around the camshaft based on feedback from here and also from the mechanic. So, I'll take a look at it in the next few days.

Hello...

If your engine also has the two camshaft wheels like mine (BKD), then theoretically, I could imagine that the belt tension between those two wheels might be too high. If I remember correctly, this tension is adjusted last.
In various reports, this tension is often overlooked because the belt seems to fit "tooth-wise," and many people misunderstand that the loose gears are related to the identified camshaft issues. Furthermore, some people incorrectly position BOTH gears in the wrong direction before installing the new timing belt, causing these two wheels to be already at their extreme positions BEFORE the belt is even tightened.
(I hope my explanation is somewhat understandable...)
That would explain why the teeth on both sides of your belt are broken.

Sure thing! Please provide the German text you would like me to translate into English. I will only provide the translation without any explanations.
Manfred.

The BKC engine, like all 1.9 TDI engines, is an 8-valve engine with a camshaft.

Jojo81 wrote:

They were replaced with the tougher ones from the ARL engine, which is not uncommon for performance-enhanced "small" PD engines. They were also tightened again correctly during the process. Since then, there has been no coolant loss after full-throttle runs (head-lift aside). But that has nothing to do with the story about the dental rim. As I said, I suspect the camshaft area because of feedback here and also from the master mechanic. Therefore, I'll take a look at it in the next few days.

Here's the translation:

"This is how you ruin a ZK seal and risk damaging the ZK itself."
Herbert.

And then what?
Warped cylinder head = stiff camshaft?

Hello.

Yes, you're absolutely right (with one camshaft wheel). However, my theory only works with a single camshaft wheel.

I contacted a colleague who has done many timing belt replacements, and he shares the same opinion as some of my colleagues here: A TDI engine probably won't "survive" one or more instances of a skipped tooth on the timing belt, or this would likely be the first case where no damage occurred... because it's probably not technically possible.

In my opinion, something is noticeably harder to move than usual and requires more force.

For me, it would make some sense if the problem originated in the rear wheel, although I also think the damage to the timing chain originates at the crankshaft sprocket because a much greater force is transmitted there, and the contact area and radius are significantly smaller than at the top.

Have you ever seen the LLR?
If something is broken or damaged, it simply can't function properly or look good, no matter what.
Regarding the twist angle...

Some other "actions" are quite peculiar and may not exactly be considered optimal...

Sure thing! Please provide the German text you would like me to translate into English. I will only provide the translation without any explanations.
Manfred.

We could keep complaining for a long time... but that won't solve your problem, just like a new timing belt wouldn't.

If everything were still okay with me and the rest of the vehicle, I would take the head off right now and examine it.

Reasons for this:

Repeated timing belt breakage or tooth stripping will almost certainly lead to a collision between the pistons and valves.


Your suggestion to replace the ZK screws doesn't seem sensible given the proposed procedure.


After that, decide what needs to be done. It's possible that traces of the NW (Northwest) can already be detected when removing the valve cover, but this requires quite a bit of disassembly.



Otherwise, there's nothing much to say about the topic itself.

There's only one thing to do: get your head down, take it apart, and examine it! Everything else is pointless.

Either the needle valve is stuck in its bearings because the valves are seizing at high temperatures, or the valves are compressed and jammed in their guides.

P.S.: The front wheel and the rear wheel also need to be replaced... they will have likely been affected by the prolonged stress.