Your car’s wheels spin around, the pistons go up and down. So the question is how you take the lateral movement of your pistons and turn it horizontal to make it rotational energy? The answer is your crankshaft. It takes all the energy from the pistons and sends it to the transmission. This is super important, it’s the centerpiece of your internal combustion engine.
Your crankshaft is rotated by the pistons and remains balanced while spinning at very very high speeds. It also has a pulley attached to the end of it. This pulley is what powers your alternator, air conditioning compressor and various other things. As you can tell, it’s a really critical part of your engine block assembly.
What is a crankshaft?
The crankshaft is a metal shaft, usually made of a high strength steel composite or sometimes even forged steel. It needs to be strong because it transfers energy via a cranking motion. If you’ve ever seen an old school train and how that rod spins the wheel, that’s what the connecting rod does with the crank.
It is bolted to the flywheel and the crankshaft pulley. There are a few key bearings that allow it to spin both of these, while not damaging or moving anything else. Your rod bearings cushion the rod as it rotates. The big end bearings ensure that the crankshaft can rotate independently of the block.
To keep your rods attached while they spin at such high speeds, you have main rod bolts. To keep your crankshaft attached to the main block while it spins, you have main bolts. Pretty inventive names, I know.
Your crankshaft is balanced. As you can imagine, spinning a shaft from a bunch of different angles, with different weight positions, creates a problem. The crankshaft is weighted and has internal or external balancing to allow it to rotate perfectly smoothly.
How does a crankshaft work?
The cranking motion is generated by the piston travelling up and down. As it travels, the connecting rod rotates the crankshaft around about its axis. This rotational energy is connected to the flywheel, in turn connected to the transmission. Allowing the drive shaft or CV shafts to rotate the wheels.
When you aren’t accelerating or gravity is moving the car forward, the wheels turn the crankshaft. This keeps the pistons travelling as they should even though they aren’t doing the work.
What can go wrong with a crankshaft?
If your bearings fail you can scar the crankshaft and require expensive machining. The cost of getting it in and out of the car is far worse.
If you damage a connecting rod and thus damage the crankshaft it may require a new one. That is incredibly expensive and will usually total an engine.
How do I prevent engine damage?
You take care of your car.
Have your oil changed regularly. Have it serviced, inspected and maintained as required.
We can help you do all of this, at a cheap price too! Just click here to book in for your servicing or any other work your car needs. Our partner garages will keep you on the road, all while keeping the costs down.