300 G motor oil questions

["Myles Wallace" <myles1@xxxx>]

A couple general and specific questions regarding engine oil for my 300 G project.

I changed the oil recently with 5 quarts of 10W/40 -- any thoughts on the grade which is recommended? 

The oil tube and stick do not appear to be original (no stopper on the stick like the transmission stick). What is the factory length of the stick? Any channels into where one (used, or repo) can be acquired?

Lastly, I have an oil leak and it appears to be coming directly from the filler cap. With the oil change I cleaned the cap and resoaked it in oil. What could be causing a decent amount of oil lose through the cap? 
- Could it be air coming through the stick tube described above? 
- What about a bad PCV value (frankly I can't seem to locate one --- do these 413 max wedge cross rams have one?) 
- Or could it be a vacuum leak (I do have the lines to the air/heater controls disconnected as I work on the switch in the console) 

As always, thanks for the input. BTW, planning on giving an update on my electrical challenges soon -- thanks for all the feedback -- most helpful.

Myles


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