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I had a spare LZx cam phaser I decided to take apart to see how it operates, I didn't take any pictures before disassembly. There's a small snap ring that holds the phaser return spring in place, if you take one apart, beware, the spring is under stress.
that leaves the phaser looking like this, it also uncovers a smaller spring, and a check ball in a cage. the smaller spring is on the table to the left. I assume the function of this part is to act as some kind of a pressure relief, but I'm not 100% sure. this part is where the phaser gets oil from a drilled passage in the camshaft.
flip the phaser over and there are three bolts in the bottom, remove the bolts and the phaser comes completely apart.
there's a spring loaded pin that "parks" the phaser in near the most advance position, it has oil ported on the retard side of the phaser, so that pressure applied to retard the cam also unlocks the pin. there's a bleed port on the front of the phaser that prevents the pin from hydraulic locking.
there are 6 seals inside the phaser, 1 at each apex of each phaser vane, and one at the root of each phaser vane, as far as I can tell, they're all the same part.
the phaser just sets in the housing, in this picture you can see a drilled port in the side of the phaser, approximately centered this port is plugged by a ball bearing, it's the drill hole that allows oil from the oil inlet to get to the center of the control valve
this shows the inside of that hole, note, there are also holes above and below that hole, and that those holes are offset, these are the feeds to advance or retard the cam.
here's outside of a pair of those holes. notice they're close to the vanes.
the ports close to the cam sprocket retard the cam, the ports away from the sprocket advance the cam.
this is the control valve oil is ported into the center, and the valve in it's resting state ports oil to the front port, advancing the cam, as PWM frequency goes up, the valve slowly blocks the feed to the front ports, and opens the ports to retard the cam.
that leaves the phaser looking like this, it also uncovers a smaller spring, and a check ball in a cage. the smaller spring is on the table to the left. I assume the function of this part is to act as some kind of a pressure relief, but I'm not 100% sure. this part is where the phaser gets oil from a drilled passage in the camshaft.
flip the phaser over and there are three bolts in the bottom, remove the bolts and the phaser comes completely apart.
there's a spring loaded pin that "parks" the phaser in near the most advance position, it has oil ported on the retard side of the phaser, so that pressure applied to retard the cam also unlocks the pin. there's a bleed port on the front of the phaser that prevents the pin from hydraulic locking.
there are 6 seals inside the phaser, 1 at each apex of each phaser vane, and one at the root of each phaser vane, as far as I can tell, they're all the same part.
the phaser just sets in the housing, in this picture you can see a drilled port in the side of the phaser, approximately centered this port is plugged by a ball bearing, it's the drill hole that allows oil from the oil inlet to get to the center of the control valve
this shows the inside of that hole, note, there are also holes above and below that hole, and that those holes are offset, these are the feeds to advance or retard the cam.
here's outside of a pair of those holes. notice they're close to the vanes.
the ports close to the cam sprocket retard the cam, the ports away from the sprocket advance the cam.
this is the control valve oil is ported into the center, and the valve in it's resting state ports oil to the front port, advancing the cam, as PWM frequency goes up, the valve slowly blocks the feed to the front ports, and opens the ports to retard the cam.
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