Ok I have a 90 s10 4.3 blazer vin z tbi newly rebuilt engine and it seems after all the pain of putting this together I have a oil leak.

I notice that the leak only occurs when the engine is running and it seems to be on the passenger side only so oil adapter is not the cause, but replaced with new anyways because old ones were worn out. The drips occur on the starter bolts and the passenger side dust cover bolts.

My suspicion is that I have one of four things occuring

1 rear main
2 valve cover
3 rear oil pan gasket
4 intake leak/ oil sending unit

In my suspicion i have checked two of these valve covers and intake/ oil sending unit.

how can i get the dust cover off to inspect if it is one of the two worst?

In addition I forgot to add I don't want to remove anything I don't have to lol

front drive shaft?

exhaust?

transmission line to rad disconnect?

thanks for replys

 

I would look higher up, but you can pull the dust cover and have a look at the front of the flex plate. If the flex plate is dry, then the rear main is intact and sealing properly.

As far as higher up, check the back of the intake manifold, the gasket at the bottom of the distributor, and the valve cover gaskets. All three are somewhat common leak points, especially if things were opened up and not correctly reinstalled at some point in the engine's history.

Clean up the oil with some degreaser so you can get a better look at finding the source.