SS Specific Service Issues/Repairs Service/Repairs specific to the SS. Turbo-Brembo Brakes-2.0 Engine-Limited Slip Differential-Programmable Display-MU3 Transmission

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Old Feb 7, 2025 | 11:20 AM
  #1  
guppy's Avatar
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Top Dead Center

I plan to finish my timing chain job this weekend, hopefully. I need clarification. Currently the old chain is stil on it in the picture. Is this position considered top dead center? Crankshaft key on top, exhaust cam mark at 11 o’clock, intake cam mark at 2 o’clock. Piston is at the top. I took pic of lifters, not sure what I am looking at though. Does this look right?






Old Feb 7, 2025 | 01:34 PM
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Don't worry about TDC! Just put the chain on the marks. Taking it off at TDC is just for convenience and is determined by putting a stick or a screwdriver in #1 spark plug hole and eyeballing the highest point. When the crankshaft key is at 12:00 one of the pistons will be at TDC (whichever one has both valves closed).

Do not turn the crankshaft counter-clockwise!
Old Feb 7, 2025 | 01:38 PM
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Don, what I see is confusing me. The timing marks look good. But the valves on #1 cylinder, it looks like one intake valve is open and one is closed. Same for the exhaust valves. Am I just seeing it wrong?

Maybe the view is just blocked by the divider.
Old Feb 7, 2025 | 01:59 PM
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The cam marks are totally wrong and #1 has intake closed and exhaust open in pic #4, in #5 they are obscured a bit.
The marks should line up with the colored links.
I think guppy is working with incomplete information. There is no reason to agonize about TDC!!!!!!!!!

That old how many rotations does it take to get all 3 marks lined up in a 4 cylinder engine thing.
Old Feb 7, 2025 | 03:01 PM
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Read this……

https://www.ddmworks.com/assets/imag...uild%20Kit.pdf
Old Feb 7, 2025 | 03:40 PM
  #6  
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I see the exhaust (on the left) cam phaser(sprocket) with a triangle mark at about 10 and the intake phaser with a diamond mark at about 2. Like you said, when you're putting in a new chain, that is just for convenience.

Crankshaft key is about 12. So the marks look good to me.

I see now that the view is indeed blocked. If the camshaft lobe isn't on the roller, then the valve is closed, correct? I can't see any lobes on #1 cylinder rollers, so all 4 valves must be closed. Just to contrast, it looks like cylinder #2 has intake valves open and exhaust valves closed.

It looks, to me, that Guppy is good to go.
Old Feb 7, 2025 | 05:57 PM
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Man guy. So long as the marks are in the right position it's in time.
Old Mar 5, 2025 | 11:41 PM
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What happens if you turn the crank counter lock wise? I did that a little trying to get camshaft sprockets in position.
Old Mar 6, 2025 | 05:22 AM
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The chain could jump a tooth. But check and double check , you’re good to go
Old Mar 6, 2025 | 11:45 AM
  #10  
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So I turned the engine over with a ratchet (clockwise) multiple times, so I am good, otherwise the valves would hit the piston and I could not turn it correct?



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