ALH Injector Pump: Disconnect for Timing Belt Change

Hello everyone,

Okay, I'm currently changing the timing belt on my ALH engine.
My first TDI swap...
Okay, I found the OT (Over Timing). Some time ago, I replaced the dual-mass flywheel (ZMS) with a single-mass flywheel (G3 VR6, identical to the 1Z TDI).
The camshaft can be easily locked in the top dead center (TDC) position.
However, in that case, the centering pin will not fit into the ESP.
When I lock the ESP with the dowel pin, the camshaft alignment tool fits just barely - however, it then no longer aligns properly with the top dead center (TDC) mark.
What might be the reason for that?
Could it be that the marking on the flywheel is not 100% accurate?
Or was so much adjusted at the start of the injection process during the last changeover that the combination of "OT" (presumably a reference point), a ruler, and a centering pin simply doesn't fit anymore?

Sorry, as I said, I don't have enough experience yet.
Thank you very much and best regards!

Hm, let's try a different approach:

Can the ESP be locked in only one position?
I still plan to install a different type of plunger in the pump.
Then I could block the NW (Northwest) port and set the KW (Kupplungswelle - coupling shaft) to OT (Oberer Totpunkt - top dead center), remove the pump, replace the piston, secure it in the only possible position with a locking pin, and then install the new belt, right?

Quote:

Or was was adjusted at the beginning of the last changeover, such that the OT plus ruler plus centering pin simply doesn't fit anymore?

Have you ever thought about the fact that the belt stretches over time, which can slightly alter the valve timing (intake, exhaust, with the exhaust timing shifting later) ?

Highlight all the points with a marker pen or permanent marker. This will help to avoid major mistakes.

Hello!

I've been through that before too.
It's quite annoying to have to disassemble half the car just to get to the timing belt, but that's not what we're talking about here...

I personally have developed a habit, due to negative experiences, of...
always attach a timing belt and a marking to each wheel.

Then, the old timing belt is removed, and the markings from the old timing belt are transferred to the new one.
And just like that, it's back on...

However, the fuel injection pump timing is still not correct for me, as I unfortunately discovered.
I need to take care of something else there as well.