Engine Components

The same vehicle model can have several engines, and the same engine can be updated during production. Pistons, gaskets and timing parts often change with those updates, so the engine code and production date identify the correct parts.

After machining a worn cylinder or crankshaft, parts with larger piston diameters or thicker bearing shells are used. Oversize pistons are larger than standard; undersize bearings fit a crankshaft journal ground smaller than standard.

Many modern diesel engines use head gaskets in several thicknesses. The correct grade is selected by measuring how far the pistons protrude above the block deck. Using the wrong grade can cause poor compression or piston contact.

Kits suit standard rebuilds where the scope is known. Where machining reveals unusual wear, individual parts in the required sizes are often needed. Many rebuilders use both.