I'm in the process of purging my lube lines to unclog the lines.

On my manifold inside the cabinet I have (4) Lines

One is the X-Axis
One is the Y
One is the Z

But I'm not sure what this extra line is ( the one with the yellow arrow )

I'm guessing the spindle? ( but isn't that being lubed from the oil tank at the bottom of the cabinet? )

Thanks,

Kent

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