Abstract: An expandable plug particularly adapted to plug an engine's oil pan drain hole. The expandable plug includes a threaded bolt, a compression plate assembled with the bolt, and a compression nut assembled with the bolt and adapted to bear against the compression plate. A resiliently deformable section of tubing is assembled in slip fit relation with the bolt, the tubing section being axially compressible and radially deformable but not being a specially molded part. With the plug located within the pan's drain hole, tightening of the compression nut causes the tubing section to bulge outwardly into a liquid sealing with the hole, and also to bulge inwardly into liquid sealing relation with the bolt, thereby plugging the drain hole against oil flow therethrough.

Abstract: An installation tool for installing a cup-shaped freeze plug in an engine block's bore. A reciprocable hammer nose connectable to a power source repetitively hammers the freeze plug to drive it into the bore. One feature includes a hammer stroke adjustment system which permits the stroke depth of the hammer nose into the block's bore to be adjusted by the tool's user in order to seat the plug at a pre-determined depth in the bore. Another feature includes a housing particularly sized and configure to cooperate with a freeze plug of the type having a minor diameter base section adapted to be slip fit into the block's bore and a major diameter rim section adapted to be pres fit into the bore, the plug's rim being received internally of the housing when the plug's base is slip fit into the bore, and when the housing is engaged with the outer surface of the engine block so as to align the plug and the tool and the bore properly prior to hammering the plug's rim into the bore.

Abstract: A cup-shaped freeze plug for a coolant hole in an engine block. The plug includes a base section having a diameter less than the hole's nominal diameter, the base diameter being sized to permit the plug to be hand-fitted into the coolant hole at an intermediate non-sealing position. The plug also includes a rim section formed integral with the base section, the rim section having a diameter greater than the hole's nominal diameter, the rim diameter being sized to allow the plug to be force-fitted into the coolant hole at a final coolant sealing position.