It sounds like a prop from a 1950s B-movie. The harmonic balancer. You imagine aliens or hobos singing on a train. It isn’t. This is why the crankshaft does not break.
The engine is a violent place. Pistons fire up and down. This energy is converted into torque. The torque acts on the crankshaft. The crankshaft turns the wheels. Simple.
But there’s a problem.
The ignition of each cylinder provides power to the crankshaft. This force twists the shaft. That resonates too. Resonance makes the vibration worse. If the engine hits certain frequencies, the vibration intensifies. It cracks. It fails. Your car will stop. Your wallet is empty.
The harmonic balancer stops this.
It is a circular device. rubber and metal. Attach it to the front of the crankshaft with a bolt. Usually connected to the crank pulley. This pulley runs the air conditioner and other accessories. The rubber inside is the hero. It dampens vibration. It keeps them safe.
Mechanics also call it a “dampener.” It’s the same part. A better name.
The rubber deteriorates. Time kills the rubber. When the balancer goes bad, you will feel a strong vibration. The crankshaft can crack. The serpentine belt might fly off its track. Replacement is preventive maintenance. Do this before the damage happens.
Removing the Old Unit
I’m thinking about replacing it. OK
Good news: Putting on a new one is easy.
The bad news: taking the old one off is not.
You may need to remove the body panels. front fender. bumper. Radiator. All engines are different. You should check the forum for your own model. But overall, the process is brutal.
You need a tool. A harmonic balancer puller.
You probably don’t have one. You need to buy it. The price is about $25. It removes the balancer safely. It also works on gear pulleys and steering wheels. Don’t skip this. Because you don’t want to damage the crankshaft threads.
The process starts with the belt. Remove the serpentine belt from the crankshaft pulley. Remove the mounting bolts with a socket and ratchet. Next, attach the pulling tool. Crank it down. The balancer pops off.
Installing the New Part
Reinstallation is reverse engineering.
Compare old and new parts. Check the location of the bolt holes. they must match. If not, you have the wrong part.
Torque setting is important. Use a torque wrench. Follow manufacturer’s specifications. If I had to guess, the thread broke or the new rubber is cracking.
Start the engine. Listen. Watch. If the vibrations don’t rattle your fillings loose, you’re doing it right. If that happens, you’ve missed a step.
Costs and symptoms
How much does this cost? About $200. Parts and labor.
Why is this important? A bad harmonic balancer can cause crankshaft failure. Replacing the crankshaft is expensive. Balancers are cheap.
Symptoms include rough engine vibrations. A serpentine belt throwing off. cracks in the rubber.
Can you drive with a bad one? No. Vibration can damage the crankshaft. You will be towed. Your wallet empties.
Change it. It’s not difficult. Don’t skip the pulling tool.
