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This is TDC, right?

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Putting my stroker together and am at the point where I've installed the front cover, oil pump and distributor drive shaft. The L24 engine FSM says to put piston #1 at TDC and shows a photo of the dizzy drive shaft at "11:25" with the smaller lobe towards the front.

Now, I've prettied up my crank pulley and timing gauge and this is what I believe it should look like when at TDC. My confirmation is the dizzy drive shaft orientation. Frankly, I don't know why the FSM didn't have a similar photo of the pulley/gauge as well as the dizzy drive shaft orientation.

Just want to confirm with you engine guys that I have it right.

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  • Author

Thanks. I never knew of the screwdriver alignment test. I was apparently off by one tooth on the dizzy drive shaft / crankshaft spiral gear engagement. Now rectified.

TLTR - might be that that damper doesn't go with that degree marker.

You have an early damper with a later degree marker/pointer. I'm not sure that zero is in the same place. Besides the fact that it looks like an old damper. And, on top of that, some of the early dampers were marked for a driver side pointer. If it was mine I would use piston position to verify zero. Since you have everything apart and in front of you.

I can't find a decent picture of a 240Z marker out on the internet for some reason. I think I made AI mad and it's blocking me. I did find one old one though, linked below (site is in it!, and me!). It looks like the pointer used for zero with the notched damper pulley is right under the bolt head where with the later marker (yours) the bolt head is at 5 degrees. Don't know, just saying it's worth confirming.

The guy in the thread also had a displaced damper apparently. Didn't get a final response.

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  • Author

I have, indeed, verified with my inspection camera that piston #1 is at the top of its travel when the damper and pointer are in this configuration so I'm confident in how things are currently set up. Or perhaps the stars have just aligned for me.

Of course, the truth will out when I fire up the engine.

Be sure you are on the compression stroke. Both cam lobes on #1 piston are pointed up, like "bunny ears".

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