1968 302 oil passage plugs

11-01-2009, 12:44 PM
I'm a first time engine rebuilder and have a question about oil passage plugs in the front of the motor. The reference material I'm using says there are 3 but does not show where they are located. It appears there are 2 left of the cam and 1 above and right of the cam behind the distrubitor shift. Is this correct? Also above the cam to the left there's a rough opening in the block about a 1/2 or so. Is this normal?

11-02-2009, 08:21 AM

Yes, this is all correct and "normal". If the engine rebuild is relatively stock, the pressed-in plugs are fine. Be sure to "swedge" them round the edges so they can't pop out. We use a sharp chisel to "fold" a small area of metal over the plug at 12-6 and 3-9 ("o'clock").

If this is a performance build, where it could "catch revs" quickly, it is recommended to tap the holes for "srew-in" pipe plugs. The holes are the correct size for 1/4"-NPT plugs. SOME blocks ARE "screw-in" plugs, but the vast majority we've seen are not.

The "rough" hole you refer to is a "return" hole (where the oil drains back from the valley).


11-02-2009, 04:22 PM
Thank you!

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