DIY Video: How to install threaded engine-block oil plugs


In this installment of Hagerty DIY, Davin Reckow is working on a 389-cubic-inch Pontiac block fresh from the hot tank. In order to properly clean the block, the plugs blocking the ends of the lifter oil gallery had to come out. Otherwise oil sludge may have remained that could later block a passageway and lead to oil starvation. It’s an easy upgrade for guaranteed peace of mind, since tapped oil passage holes make sure that pressurized oil stays where it should be.

This is a companion discussion topic for the original entry at https://www.hagerty.com/articles-videos/articles/2018/04/13/diy-install-threaded-engine-block-oil-plugs


A used “Tapping Head” is an inexpensive accessory that is great to have if you do any amount of tapping. Some have a tapered input shaft to fit in place of the chuck. It will provide clockwise motion till you back off the feed at which time the direction will reverse automatically. Always use the slowest speed - if using a vertical miller like a Bridgeport it would be in “back gear”