And because the belts that go around the crankshaft pulley run all of the car’s accessories, without the harmonic balancer you’d have no air conditioning, no power steering, no alternator and no water pump. And without it, you can do damage to the crankshaft and the engine bearings. So you really do have to replace it.

Bad Harmonic Balancer: Signs to Watch Out For

1. Engine Vibrations. The harmonic balancer’s job is to dampen vibrations applied to the crankshaft.
2. Noticeable Harmonic Balancer Wobble.
3. Unusual Noises.
4. Illuminated Check Engine Light.
5. Visible Wear or Damage.

It’s not okay to drive with a bad harmonic balancer. The bouncing crankshaft will wear on the main bearings. It can also tear up drive belts and possibly come apart posing a danger to people and property. And without it, you can do damage to the crankshaft and the engine bearings.

Noisy Belt Operation or Damage The harmonic balancer also acts as a pulley for your vehicle’s drive belts so when it begins to fail your engine’s belts may slip, operate noisily or become damaged. You may experience this as an inability to accelerate efficiently, dips in fuel economy and engine misfiring or backfiring.

Yes you can start you motor without a crank pulley.

How the Crankshaft Pulley Reduces Damage. Located outside the engine block, the crankshaft pulley is essential to ensure other engine components operate in unison to allow the vehicle to run smoothly.

Similarly, if the belt tension is too strong or the auxiliary equipment has failed the pulley will also fail. The cause is linked to the coupling having made contact with the flywheel rim. The crankshaft can bend severely or even break in some cases. …

The crankshaft position sensor is the most important of all engine management sensors, and the engine will absolutely not run without it. Many systems are smart enough to try guessing should this sensor fail and allow the engine to run without it. In your case, a magnetic crankshaft positioning sensor is used.