Clapped-Out Mk3 restoration help  

Clapped-Out Mk3 restoration help

I bought a second Mk3 from a print farm.  This thing has been rode hard and put away wet.  21,670m of filament and 486d of print time.   All black ASA, in an enclosure.  There was black dust caked into everything.  And the Z screws there over lubricated with ASA contaminated greese.  

I've replaced both fans, and cleaned everything.   The bed slinger belt seems a bit loose but not terrible.  Simple single layer things like boxes with no infill print fine.  It  print a decent benchy.

I can get a good a fair first layer calibration.  But when I try to print something larger I get strange artifacts in the first layer.  These artifacts always happen in the same place in each print try.  When the first layer of infil starts it's like some of the infil lines get knocked off.  Then the print gets to the first layer where we need to bridge over infill (20%). I get, what I could only call "pillowing" on that layer.  To the extent that eventualy the head crashes and the print stops.

Looking for some advice on what to check next.

All prints done with Oveture PETG.

In the photos it looks like the first layer is too squished.  Like Z needs to come up a bit.  However this is as high as I can get it and still get adhesion.