Engine blocks, are home for the, cylinders, crankcase, top deck, oil galleries and water jackets.

First, made from heavy cast iron. Then, came the big push for, better fuel economy. As a result, the next step was to move to, lighter and cheaper aluminum alloys.

So, this is where the crankshaft spins and the pistons, move up and down, in the cylinder bores. However, on many older engine designs, it also held the camshaft.

In addition, engine blocks, come in different configurations, including, V Cylinder, Inline Cylinder and Opposed Cylinder Designs.

Components Of An Engine Block Include:


They are large in size and have precisely formed holes, to create a seal with the piston.

Oil Passages or Galleries

These allow oil to reach, the cylinder head and the crankshaft.


This is the top surface of the block, where the cylinder head sits.


This houses the crankshaft and is found, at the bottom of engine blocks.

Water Jackets

This water jacket, is an empty system of passages, used for circulating engine coolant.

Common Problem

Worn/cracked block

Eventually, after hundreds of thousands of miles, the smooth machined walls of the cylinders will wear. Consequently, the cylinder wall can also develop a crack. And, can quickly result in, a engine needing a rebuild.

Engine overheating, is the most common cause of a cracked block. When the engine gets too hot, the block can crack, as a result of thermal stress. Also, the block can crack, in freezing temperatures. Consequently, if the cooling system is filled with, too much water and not enough antifreeze. So, cracks are usually terminal. However, if the crack is in a cylinder, you may be able to save it, by installing a cylinder sleeve.

Choose Your Engine Blocks Help Topic Below

Cylinder Sleeve – How To Install A Cylinder Sleeve To Salvage A Block

Ball Hone – How To Get The Perfect Finish For Piston Ring Sealing

Piston Rings – Signs Of Worn Piston Rings And How To Replace Them

Engine Bottom End Components – Know The Parts Inside Your Engine

Cylinder Bore Deglazing – Purpose – Crosshatch – Roughness And Angle

Thank You !