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I was following these instructions:

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and I got a little confused because I couldn't tell how to check whether the timing marks were in the right position. I since figured out how to do that but the timing got all out of whack as I was messing with it.

The instructions said the front cylinder bank cams should be in the neutral position. I take this to mean all of the pistons should be the exact same height from the top of the cylinder head, right? Well, they're not. All three pistons are at different heights.

Anyways now that the heads are off I've kind of got to figure this out without any help from the book. Does this plan make sense to you?

Find top dead center of #1 piston by rotating crankshaft and observing it's highest point.

From there the instructions tell you to turn the crankshaft from 11 o clock to 3 o clock and the 1 2/3 turns back to 11 o clock. It's at this point that the front cylinder bank camshafts would be in the neutral position. As long as the pistons in the front cylinder bank are all the same distance from the top of the cylinder head I should be good to go, right?

Another question I have is do I have to account for whether or not the crankshaft is on the compression stroke or exhaust stroke when executing my steps above? How does the engine know if it's on the compression or exhaust stroke? Does it figure that out dynamically?

Finally, I know how to position the cams because there are timing marks on the cams, timing chain, and crankshaft that all you have to do is line up. But I am a teency bit concerned that the crankshaft won't be in the EXACT right position if I do this. I mean, it will be easy to stick a ruler into the cylinders to make sure each piston is the same distance from the top but I;m still worried it won't be perfect. So that and hoping I don't accidentally mix up the compression/exhaust stroke, if that is a thing I actually have to worry about, are my main concerns. Thanks so much.

Oh, and guess what, All three bolts on the rear transaxle mount were broke. Not my fault, I never touched em. But now I have to take out the dang transmission to get those bolts out.

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    I'm not clear what it is you are asking. If you have the procedure from the Service Manual, then follow that procedure. The timing marks on the camshafts and the crankshaft are what governs this. Follow the instructions carefully and exactly.
    – jwh20
    Commented Mar 2, 2022 at 15:29
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    The position of the valves determine the compression/exhaust stroke.
    – HandyHowie
    Commented Mar 2, 2022 at 15:58
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    When you put the heads on you need to make sure the pistons are not near the valves, hence the neutral position.
    – HandyHowie
    Commented Mar 2, 2022 at 15:59
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    Yes, but they don’t need to be equidistant, just away from the valves. Yes, the ECU will use the cam position sensor and crank position sensor to decide when to inject fuel ready for the intake stroke and trigger the ignition. You need to make sure both cams and crank are in agreement by following the correct procedure for attaching the chain.
    – HandyHowie
    Commented Mar 2, 2022 at 17:29
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    One thing I don’t get about your diagram is that it says that the left bank (front) cams need to be at 12 and 9 o’clock, yet the diagram shows the right bank (rear) being in those positions. Maybe the context of the diagram will make it clearer.
    – HandyHowie
    Commented Mar 2, 2022 at 17:35

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