Camshaft vs. Crankshaft: What They Are and What They Do

Both important parts of your engine, the crank and cam shafts are rods (or shafts) that extend through the engine and are connected to different parts of the engine by belts, gears, or a chain.

The camshaft controls the opening and closing of valves through the combustion process, and the crankshaft takes the energy from that process and connects it to the rest of the vehicle.

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What Are The Crankshaft and Camshaft?

1. 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 drives 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 exactly 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, with one camshaft controlling the opening of the intake valves, and the other camshaft controlling 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.

However many are featured in your engine, they are controlled by a series of belts, gears or chains to ensure precise timing. Late model vehicles incorporate a Variable Valve Timing Solenoid that adjusts the camshaft lift and duration based on engine demands.

2. Crankshaft In Depth

While the camshaft helps your engine create power, the crankshaft takes that power and gives it to your vehicle. Another long, metal rod, your crank shaft 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 its own connecting rod which attaches to the piston, taking the power generated from the piston’s motion and transferring it to your transmission for your car to use.

With big words, it converts reciprocating motion (the up and down of the pistons) into rotational motion (the spinning of the camshaft into the transmission). Like the camshaft, the crankshaft’s timing is managed by a belt, gears or chain. Keeping the timing components in good shape, is the best practice thing you can do to maintain proper engine timing.

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

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