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Newly rebuilt and installed engine. With No 1 piston at TDC (cam lobes outwards) and distributor rotor pointing forwards-ish like it should, the timing pointer is a good half-inch anti-clockwise of the P mark (looking from the front). Is that something I should be concerned about?
 

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Better to determine by putting something down the number one spark plug hole and measuring when the piston gets to the top of its travel. I just use a two inch dial indicator dropped in the hole.
with piston exactly at tdc then, you can tweak your pointer to be exactly at the P mark. Usually it just needs a smidge if anything.
 

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The timing marks on the camshaft and the caps align, and the lobes on No 1 cylinder are pointing outwards.
Terry
Use @vintagemilano method to align the pointer on the pulley mark. The pistons and crank pulley are keyed together. It sounds like your camshafts may need to be adjusted to get them pointing at the timing marks, but they may not be exactly on the mark.
 

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Use @vintagemilano method to align the pointer on the pulley mark. The pistons and crank pulley are keyed together. It sounds like your camshafts may need to be adjusted to get them pointing at the timing marks, but they may not be exactly on the mark.
This is how the camshafts are set:
1663673
 

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Yep need to confirm No. 1 is actually at TDC. Always the starting point, and cannot be assumed

Pete
 

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No, that’s my concern - the pointer is about half an inch anti-clockwise from the P.
Terry, we cannot verify the accuracy of the pointer until you confirm where the number 1 piston is. You cannot use the camshaft marks for that, because it is possible that they are wrong.

To find the TDC of the number 1 piston you need to remove the number 1 cylinder's spark plug and put a wooden dowel down until it touches the top of the piston. Rotate the engine clockwise until the wooden dowel is at it's highest, AND number 1 cylinder is firing.

Then we can look at the pointer and see where it is pointing. If it is pointing at P, your valve timing is wrong. If the pointer is pointing somewhere else, "we" have a bigger issue
Pete
 

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I agree - you really have to accurately locate TDC first. When the piston is a few degrees before or after TDC the piston barely moves. Using Pete's dowel in the spark plug hole tool, first make a mark on the dowel at approximate TDC (say at the top of the spark plug hole). Make another mark about 1/2" below that. Turn the engine until the second mark is at a repeatable position (at the top of the spark plug hole) & make a temporary mark on the crankshaft pulley next to the pointer. Now turn the engine a little more - past approximate TDC - until the second mark is back to the same place as before (at the top of the spark plug hole). Make another temporary mark on the pulley. Actual TDC will be half way between the two temporary pulley marks. Turn the engine in the 'forwards' direction until the pointer is aimed at the point halfway between the two temporary marks. Re-align the pointer to be aimed at the P mark on the pulley.

Re-check the cam timing marks
 

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Discussion Starter #14
Terry, we cannot verify the accuracy of the pointer until you confirm where the number 1 piston is. You cannot use the camshaft marks for that, because it is possible that they are wrong.

To find the TDC of the number 1 piston you need to remove the number 1 cylinder's spark plug and put a wooden dowel down until it touches the top of the piston. Rotate the engine clockwise until the wooden dowel is at it's highest, AND number 1 cylinder is firing.

Then we can look at the pointer and see where it is pointing. If it is pointing at P, your valve timing is wrong. If the pointer is pointing somewhere else, "we" have a bigger issue
Pete
Pete, if the pointer IS pointing somewhere else, what would the ‘bigger issue’ be? (Not sure I want to know the answer!).
 

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Yes, silly comment of mine. Let's wait and see

Pete
 

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has your car got one of those adjustable pointers? Maybe that was messed with?

I can't quite tell, but the photo of the cam notch...is that the inlet side? (edit: ah, yes I can see it must be inlet, as the cam is pointing out to the right)
has it got a VVT?
where is the mark on the exhaust side?

(you don't say whether your car is carb UK or injected.......I am just presuming it is an S3 because that is what is in your avatar.....you might be talking about someone's S2.....best to always say
 

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Discussion Starter #17
has your car got one of those adjustable pointers? Maybe that was messed with?

I can't quite tell, but the photo of the cam notch...is that the inlet side? (edit: ah, yes I can see it must be inlet, as the cam is pointing out to the right)
has it got a VVT?
where is the mark on the exhaust side?

(you don't say whether your car is carb UK or injected.......I am just presuming it is an S3 because that is what is in your avatar.....you might be talking about someone's S2.....best to always say
hi Dom, it is an S3 on Webers. No VVT. The cam marks are the same on the exhaust side. I’ve just spoken to the guy who built the engine and he said that because the new water pump hadn’t arrived at the time (I initially ordered the wrong pump) he used the old pump as a guide, and hadn’t looked again at the marks when he fitted the new pump. He did say that he set it up at tdc, so that shouldn’t have changed.
Unfortunately I don’t think I have the old pump now, to compare.
Are there any other factors that could have put the timing out after assembly?
 

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well, no, it can't go out of timing on its own if it was assembled correct.

If it were my car I'd want those cam marks to be spot on with a stock engine.....look at the below photo of the exhaust cam.....dead on

But I think I see a problem: can you confirm, as I suspected it was, that the cam cap we are seeing in your photo is in fact the inlet side?

If your photo (below) is the inlet side AND if that number stamped on the cap is indeed a "1", then he has put the cap on the wrong cam.

cam cap inlet side.jpg

the no. 1 cap follows the no 1 stamping on the head...and that is the no 1 exhaust cam cap.
cam exhaust.jpg

but I might just be seeing things.........hopefully I am wrong, but if not I sure hope he did not mix up all your cam caps.
 

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But I think I see a problem: can you confirm, as I suspected it was, that the cam cap we are seeing in your photo is in fact the inlet side?

If your photo (below) is the inlet side AND if that number stamped on the cap is indeed a "1", then he has put the cap on the wrong cam.

View attachment 1663747

but I might just be seeing things.........hopefully I am wrong, but if not I sure hope he did not mix up all your cam caps.
Dom, I think that you may be seeing things. That looks like the exhaust cam. Note the boss in the lower right corner of his photo. That's the surround for the tappet. His cam lobe is pointing inward.
 
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