Engine Main Bearing Caps And Supports

Aftermarket main caps and supports are designed with strength in mind to handle high horsepower applications, where the downward force from the pistons during combustion meets the rotation of the crankshaft. Caps and supports help hold the bearings and crankshaft securely in place and prevent catastrophic failure when the engine is upgraded, resulting in additional stress and pressure from more power.

Installing main cap supports on your engine's bottom end helps secure the block webbing and keep the caps evenly spaced. This helps reduce distortion that can cause a spun main bearing or other engine damage caused by parts moving out of position.

Depending on the engine type, the steps to remove the bearing caps can change. However, for most engines, the first step is to remove the bolts from each block cap. Next, place the bolts back into the main cap holes and gently pry from side to side until the main caps separate. In some cases, careful use of a shot-filled dead-blow hammer may be required to help unseat the cap from the block. Once unseated, properly organize or tag the main bearing caps so that they can be reinstalled in the correct order and same orientation later. If replacing the bearings, the crankshaft will need to be removed from the block. Unless the bearings are brand new it is highly recommended to replace them at this time. Installation is the reverse of removal with particular attention paid to cap order and orientation in addition to the proper torque sequencing and bearing clearance checks with Plastigauge. Following installation instructions from the manufacturer as well as for the specific engine is always recommended as well.