I am in the process of cleaning the motor (350). After I removed a couple layers of 40 years worth of grime I discovered 2 green blotches of paint on the drivers side. There is nothing on the passenger side of the block.

Any idea why they are there?

d1

 

All I found so far is that they are factory (Lansing) inspection marks. But nothing specific as far as why or when they were applied during the assembly plant process.

d1

 

paintballers on the assembly line.

 

That does looks like the right shade of green for inspection marks.
Maybe it denotes that some part of the engine or maybe the whole engine assembly is finished?
The one paint mark looks like it has an upward drip like the engine was upside down when they daubed the paint on? Or was the paint over those marks?
If it is a drip the marks, or that suspected drip if that's what it is, would of had to have been done after the engine paint then?
If that is the case did they paint the engines upside down after the pan was on then flip them to do the top??

The marks probably were put on the engine to let a buddy down the line know he should get two more coffees from the chuck wagon at break time.
The funny part is that the assembly line workers really did do things like that that, probably still do.
My '68 GTO had a few empty Fritos bags and a couple of Pepsi cans inside of the driver's door from the factory, wonder what the code for those was?

 

Yeah, I also figured the block was upside down when the daub of paint was applied. And the paint does appear to have been applied on top of the gold.

No potato chip bags or pop cans in my ride, but I have not gone through the whole car yet.

Kind of cool to have the inspection marks, I wish I did not have to paint over them when I add the new color.

d1