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Discussion Starter #1
Hi. Just doing my first timing belt change. It’s my T5 1.9tdi BRS engine. 200k Kms. I’ve locked the crankshaft with the tool and the arrows aligned, and expected to see the camshaft aligned with the ‘4Z’ TDC arrow (the lugs should line up). But actually it’s about 2 teeth out i.e. the lugs are CCW of the TDC.

the engine was running fine I’ve had the van for 6000kms. There is a kind of loose knocking noise from the engine but I haven’t been able to locate it and am now wondering if it might be because of the potential misalignment of the camshaft...
I’m not an expert in these things so would greatly appreciate advice before putting the new belt on. Current state is crank and camshaft locked with tool and pin and old belt removed.
Also there are a couple of painted marks (see photo) which I guess are also for alignment of the camshaft and these are approximately 3.5 teeth CCW of the TDC. The tape I added to mark the current position with the crankshaft locked.
Thanks !
4BDD9C55-6174-45CA-9B25-54E8C5D4E858.jpeg
 

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Get the pin in the hole, slacken 3 bolts if necessary and see if crankshaft mark/arrow is at about 7 O'Clock. Also look trough gearbox inspection hole for TDC mark. Make sure you have the right crank locking tool, there are a few variations across the range. Also you need to adjust syncro angle with VCDS but i am thinking you best leave it there if you're having trouble changing the belt...Also make sure you put the cam sprocket bolts in the middle of the holes as there is adjustments to be done, read syncro angle above...
 

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Discussion Starter #3
Thanks for the reply. Here's a couple of pics to help explain. Everything in the pics was done before removing the old timing belt. Locking pin (right one) is correctly situated on crankshaft:
177980

But when I looked at the camshaft the lugs did not align with the TDC 4Z marking as they were supposed to:
IMG_1424.jpeg

However I was able to put the camshaft locking pin in completely (this photo with new belt on. by the way this was the position the 3 sprocket bolts were in once the belt was tensioned with both locking pins in):
177982

So what I don't understand is why the camshaft doesn't line up with the mark. I don't have access to the vehicle history so don't know if someone deliberately did that? Does it mean the timing is off (by about 1.5 teeth)? If that was the case would the engine actually run OK as it does...? In the absence of advice to the contrary I'll just put the new belt on as it is...

Couldn't find the gearbox inspection hole for TDC mark (does that exist on the BRS engine?). With regards to syncro angle with VCDS I can get that cable and do that. I hadn't come across that step in other guides to changing the timing belt.
Cheers
 

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As long as you are absolutely certain that the guide pin on the crank tool is engaged into the block (and I can see you do have the correct crank tool as you say) and the cam locking pin is going through the cam boss and into the head the relationship between cam and crank is perfect. The slots in the sprocket are going to allow the sprocket to turn slightly to allow the belt tension to be be set up perfectly but that isn't going to change that all important relationship between crank and cam. Therefore any marks on the sprocket and back plate are meaningless (in this case) because the sprocket will move slightly during tensioning process anyway.

The belt tension is critical so you will need to follow the instructions for the type of tensioner you have. Make sure to replace any stretch bolts recommended (I think it's only the crank bolt on yours) and most important of all, turn the engine over at least two full turns of the crankshaft by hand before starting the engine and recheck the tensioner alignment marks.

As Adam mentions the cam sprocket bolts should end up more or less in the centre of the slots when you have finished and you will have to allow for the fact that the tensioning process will move them a little. I think Adam was also trying to warn you that it is a deadly serious business since if you get wrong it can easily wreck your engine- circa £7000!

Re VCDS and the syncro angle, the syncro angle block shows any discrepancy in the correct relationship between crank and cam. If it is large enough it will cause cam/crank codes. Any discrepancy will be caused by (as long as correct setting tools were used) incorrect belt tension. If you get the tension spot on you should not find the syncro (synchronisation) angle much out. It is a handy way confirming your work though. Good luck! :)
 

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Discussion Starter #5
Thanks for your advice! Good to get reassurance that it's OK as it is. The Haynes manual was pretty good for covering the process and tensioning etc 👍🏼. So I'll put it all back together as it was. Out of interest, I've ordered a cable to check the syncro angle.
Do you know for what reason the "proper" marks on the back plate and the head are not aligned? I couldn't find any info on that after pretty extensive searching.
 

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Do you know for what reason the "proper" marks on the back plate and the head are not aligned? I couldn't find any info on that after pretty extensive searching.
I don't know the reason for those. There are often spurious marks that cause endless confusion. For instance the T4 5 cyl engines have crank pulley and case marks that look legit but the 'real' TDC mark is on the flywheel. Just to confuse things further not all engines are timed up at TDC. In the end, the only marks you can really trust are any shown in the manual.
 
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