Hello.

Can anybody give me an advice on this?

The lubrication section in the SM says the distributor gear is lubricated by splash from the rear camshaft bearing.
The camshaft section says this lubrication is through a hole in oil gallery end plug.
This plug in my engine does not have a hole in it.

 

I'm pretty sure it should. I've never taken one apart that didn't have it from the factory.

 

Halfway down the page - http://www.mondellotwister.com/OilingSystem.htm

A 3/8" pipe plug with a .040 oil hole in it to replace the stock left rear oil galley plug. If your oil galley plug does not have a .040 hole in it, you may experience excessive distributor gear and camshaft distributor gear wear. This plug is located behind the 29/32" freeze plug on the left rear side of the camshaft plug in the bell housing area. If left out, you could experience a serious drop in oil pressure. Sold each.

 

Getting the correct plug.
Minimal wear on the dist.gear even without the spray lubrication thought.

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