Abstract: The improved housing coupling mechanism includes a first housing such as a motor housing having a first end in abutting relationship to a second housing such as a pump housing. The first housing includes a plurality of slots arranged about the housing perimeter and in a spaced relationship one to another and from the first end of the housing. The second housing includes a plurality of bosses, each boss being configured for coupling an attachment means thereto. Each attachment means includes a fastener (such as a bolt or threaded shaft) and an accompanying plate positionable to be in engagement with one of the slots in the first housing. Each fastener is positionally adjustable in a continuum, thereby providing a force to couple the first housing to the second housing. Coupling is accomplished when each attachment means is adjusted to provide a clamping force between its plate and the slot engaged by the plate.