Trustworthy Advice:
What are the Crankshaft and the Camshaft?


The crank and camshafts are rods (or shafts) that extend through the engine and are connected to different parts of the engine by belts or a chains. The camshaft controls the opening and closing of valves through the combustion process. The crankshaft takes the energy from that process and connects it to the rest of the vehicle.

  • Camshaft In-Depth

    A camshaft is a long, metal rod with a series of external objects attached to it. The most notable are the egg-shaped lobes, which bump against the opening and closing mechanisms for intake and exhaust valves. These lobes are precisely placed and specifically timed to make your engine function correctly and as the pistons cycle through the combustion process.

    Many modern engines feature a dual overhead cam design, where two different camshafts sit on each side of the engine. In this design, one camshaft controls the opening of the intake valves and the other camshaft controls the timing of the opening of the exhaust valves. More cams doesn’t necessarily mean better; it’s just a different design. Many engines operate terrifically with a single camshaft, and there are a few quad-cam designs, or engines with four camshafts.

    Camshaft timing is controlled by a series of belts or chains to ensure precise timing. These belts are usually the first thing to check if you’re noticing an engine timing issue.

  • Crankshaft In-Depth

    While the camshaft helps your engine create power, the crankshaft transfers power to your vehicle. A long, metal rod, your crankshaft looks a little bit like the middle of a Jenga game, with its webs, pins and connecting rod journals giving it an uneven appearance. Each of these components connects with part of a piston, taking the power generated from the piston’s motion and transferring it to your gearbox for your car to use.

    The crankshaft converts reciprocating motion (the up and down of the pistons) into rotational motion (the spinning of the camshaft into the gearbox). Like the camshaft, the crankshaft’s timing is managed by a belt or chain. Keeping these belts and chains in good shape is the best way to maintaining proper engine timing.

If you have a major problem with either your crankshaft or camshaft, your engine probably won’t run. If you’re hearing a squealing sound coming from under the hood, it’s likely a timing issue related to one of the belts or chains that control these rotating elements.