So, you did this for an engine break-in period? You had someone inside maintaining engine RPMs at 2000 while you stood next to the engine thermostat cap?
If the rear cap was off when the engine was running at 2000rpms, didn't the coolant come out?
Was the thermostat installed during this time?
Sorry for ignorance, this is my first rebuild ever.
'88 Fiero GT 5-spd
'03 Jetta GLS TDI 5-spd