Crank Pulley Wobble Problems; Causes and Fixing

The crankshaft pulley is one of the essential parts of any type of engine. So, when that pulley is wobbling due for any reason, it may lead to losing efficiency, and also it can lead to many short terms and long-term problems. In this article, we discuss the causes as well as the fixes for crank pulley wobble problems. So, stick until the end with us.  

What is a crankshaft?

The connecting rod of an engine is coupled to a crankshaft, which is operated by a crank mechanism composed of a series of cranks and crankpins. Reciprocating motion is converted into rotating motion with the help of this mechanical component.

What causes the crankshaft pulley to wobble?

There is a crankshaft pulley that drives the alternator and other engine parts. The harmonic balancer is also known as the front end of the crankshaft and is placed there. You can also see the pulley on the crankshaft, although it’s not a wheel.

Using rotational energy generated by the crankshaft, various vehicle components are powered. To prevent the belt from slipping, it uses ribbing.

The crankshaft pulley’s primary function is to decrease engine vibrations.

It only rotates the belts that power the engine and other components. In addition, the alternator and air conditioner each have their own belts, which may be serpentine belts. The year and type of boat determine an individual belt or a whole system.

Condition of Rubber Belt. 

You may also see how well the rubber belt is holding up by pulling it out. As a result, it could cause timing issues and wobble.

Additionally, the crankshaft bolt that holds the pulley to the engineer may have come loose. The belt does not need to be replaced if it becomes slack. Instead of purchasing a new belt, you can just tighten the bolt.

An issue with crank bolt tightness.

Because of this, the crank bolts must be properly tightened to avoid a wobble in the crankshaft pulley. In addition, the crank keyway and the woodruff key are entirely destroyed.

A breakdown of any of the two-part assembly.

The crankshaft pulley is made up of two pieces connected by a flexible layer. The heavy metal outer component is fastened to the crank and holds the central section in place. In addition, the rotational mass reduces the intensity of the engine’s pulses when it fires.

When one of the two components fails, it should be replaced promptly.

At high RPMs, there is no wobbling effect.

You may not hear any squeaking from a crankshaft pulley that wobbles in other cases. Do not ignore such an opportunity, in my humble opinion.

You can’t hear it at low RPMs because of a center fracture in the pulley. As a result, disregarding it could severely damage the engine.

Pulley That Wasn’t Made Properly.

There are several reasons why the crankshaft wobbles, and this is one of them.

Underdrive occurs when the input rotational speed exceeds the output speed. Underdrive in the power steering, air conditioning, or alternator might have catastrophic consequences for a poorly built pulley.

Inches in length.

It’s possible that a belt is too short or has too many grooves—a five-groove belt on a six-groove pulley, for example, or the other way around. As a result, the crankshaft pulley may start to wobble.

Bad crankshaft pulley
Bad crankshaft pulley

Is the crank pulley supposed to wobble?

The crank pulley is a critical part of the engine, and it has a significant impact on its smoothness. It’s a negative sign if it’s wobbling. You may be able to get away with running it this way for years, but you also run the risk of damaging the main bearings.

How to fix the crank pulley wobble problems?

You’ll have no problem tightening the crankshaft with the factory-supplied fasteners and other thread-sealing products. Pulleys can now be used for a longer amount of time.

Be sure to double-check all of the fasteners.

A considerable bolt and a thick washer in the center attach around the pulley to the crankshaft. The shaft is held in place by four tiny bolts on the inside edge of the pulley. In both cases, the outcome is dependent on the make and model of the car in question.

All you have to do is remove the crankshaft pulley’s driving belts. You can check for slack in the bolts later. To be on the safe side, tighten all the bolts. Using a strap wrench, remove the major bolt from the crankshaft and inspect it for any damage that may have occurred. If the end of the crankshaft is damaged, the only solution is to replace the crankshaft.

Inbuilt dampener.

With an inbuilt dampener, some crank pulleys minimize the vibration running along with the pulley belt. If you do it in this manner, you can protect the system you’re connecting to from danger. Crankshaft pulley belts can be replaced individually if they become damaged or worn out. However, if a dampener fails, the entire crankshaft pulley must be replaced.

Remove the dirt.

Make sure there is no dirt, grease, sand, or belt material stuck in any of the grooves by removing the belt. In addition, inspect the smooth-sided pulley for damage, dent, or dirt.

How much does it cost to replace a crankshaft pulley?

The cost of replacing the crankshaft pulley is between $350 and $400, depending on the make and model of the automobile and the labor rate. A new crankshaft pulley will set you back between $200 and $240, and you’ll also have to pay about $150 for labor. An aftermarket crankshaft pulley could save you a few dollars.

Some related FAQs about Crank pulley wobble.

Can a loose crankshaft pulley symptom?

It’s easy to tell when the engine is idle or under stress because of symptoms such as loss of performance, engine bay vibration, and even metallic tapping as engine parts come out of sync.

Can the crankshaft pulley be repaired?

While it is possible to drive for a while with a faulty crankshaft pulley, you should have it changed as soon as possible. In the long run, replacing the crankshaft pulley could save you both time and money.

Can you replace a crankshaft without removing the engine?

Replacing the crank does not involve breaking down the remainder of the engine. Always store your rod and main cap caps together. The main rod and bearings should be replaced before the machine is reassembled.

Should a crankshaft pulley spin freely?

There are no other ways to turn the engine than either running it or using a socket and breaker bar to turn the crankshaft pulley, which is hooked directly to the engine’s camshaft and crankshaft.

Hope you enjoy the article and get good idea about Crank Pulley Wobble Problems. If you have more matters regarding this comment below and we will give you more professional solutions. And if you have Bleed Freon from Car AC check this out.

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