I am about midway done with changing the timing belt & water pump on my 1999 Toyota, which features a 6-cylinder 5VZ-FE engine. After getting the front timing cover off, I discovered that there were some paint dots on the rear timing cover, and also both cam pulleys.
(Despite the vehicle's age in years, it has rather low mileage on it and so might very well still have had the factory timing belt on it. So, I think these paint splotches are from the factory.)
For the most part, these splotches coincide with the TDC notches that are cast/cut into the cams & the back cover, but somewhat sloppily.
On the passenger-side cam sprocket, the painted dot is directly over the pulley's timing mark, but the corresponding painted dot on the rear cover is to the left of the 'V' notch.
And then on the driver-side, the painted dot on the pulley is immediately to the left of the pulley's timing mark, and the painted dot on the rear cover is to the right of the 'V' notch.
What is the point of these paint marks? What meaning are they conveying that the actual TDC markings don't? Do I need to interpret their positions relative to the TDC alignment notches in a particular way? ... And if not, why did Toyota even bother with the paint?
(There is also the puzzling matter of the additional paint splotch ~170 degrees out of phase with TDC, on the passenger side. But I'm content to ignore that one.)