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Timing chain marks and can location

Skylarking

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Is there any way to know for sure that it’s in time ? Everything lined up, after I turned it a few times they don’t line up anymore but I have been told that’s normal
The engine timing, that is the crank to cam relative positioning, must line at the beginning of the 4 stroke cycle. This must occur regardless of there being one cam chain (or cam belt) or multiple chains, belts of gears... the relative positioning must be preserved otherwise the engine won’t work...

About the only way to get the crank/cam rotation wrong (# crank turns = 1 cam turn) is to put in the wrong idle cogs (or whatever they are called) with the wrong number of teeth in the wrong position but I’d expect manufacturers would ensure such is not really possible...

So, with the correct parts installed in the correct places, after two full turns of the crank, the cam to crank relationship will be back to where it was before, presumably with the crank & cam in their correct alignment with all the marks where they should be.

It’s not like supercharging where undersized pullies can have a use... crank & cam gear must be 100% factory spec’d, timing wise, else things won’t work.

Just curious who told you it’s normal for timing, where all marks are aligned*, will not be aligned after two full turns of the crank?

*or if out by 5 teeth at the beginning will still be out by 5 teeth after 2 full crank rotations.
 

Skylarking

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@Jolls, assume you were replying to Jonathan111’s statement about being told “it’s normal” (for marks not to align again after 2 full crank turns), so not clear why you quoted me :oops:
 

Johnathan1111

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Not normal - every second rotation of the crank they should line up, There are 4 strokes of the cycle. 1 Inlet - on the inlet stroke the inlet valve is open and the piston goes down sucking the fuel air mixture into the cylinder.. At the bottom of this stroke the crank has turned 180 degress. 2 Compression - on the compression stroke the valves are both shut and the piston compresses the air/fuel mixture in the cylinder. At the top of the stroke the crank has turned 360 degrees. 3. Power - on the power stroke both valves are closed and the expanding gasses force the piston back down. The crank has turned another 180 degrees ( 540 total). 4 Exhaust. On the exhaust stroke the exhaust valve opens and the expanded gasses are expelled from the cylinder. The crank has now turned 720 degrees - two rotations. The cams and crank must be back in alignment as the the cycle continues again.
Okay so we go again that’s fine, I just want to get it right, ile turn the crank until the cam marks are at the top and go again. So left bank first in the first strange then move crank to second stage and do the crank then the right bank. Then align the chains left bank first then the crank chain and then move the crank to the first stage again and align the chain. Anything else I need to know ?
 

Johnathan1111

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Okay so the tick is coming from the tensioners not the engine, no noise from the engine and I can’t feel any problems with the crank
 

Jolls

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@Skylarking; sorry for the confusion - I was just trying to get the point across that you had already indicated it should align every second rotation.
 
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Johnathan1111

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okay, everything is back on all timing marks were aligned, I started the car and it has a very rough idle, after pressing the accelerator it smoothens out and runs fine, there is a chip in the harmonic balancer that I broke when pulling it off, will this cause this ?
 
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