Re: oil galley plugs
You need THREE plugs for the rear! One for the main gallery and one each for the left and right lifter galleries.....The NPT plug for the right side is 'hidden' behind a freeze plug/welch plug. Too easy to miss that one for those not familiar with Nailheads! Leave that out and you starve half your lifters of oil.
Originally Posted by alini
And yes, they are 3/8" NPT, internal 5/16" square drive, 3/8" to 7/16" long.
This looks like the correct Dorman, pn 090-019:
You can opt for threaded plugs for the front of the block too. Holes need to be tapped for threads, and the plug must be thin enough to not block internal passages to the cam bearing. My shop used some thin Ford plugs they had on hand.
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