There is a lot that can go wrong with a car. Each part of this machine is more intricate than the next and these parts need to work in unison. A crankshaft is one of these vital parts that you need to tend to.
To fix a faulty crankshaft, you need crankshaft grinding. It is the process through which the journals of your crankshaft are reduced in size through grinding to a minimum of 0.050 inches. It ensures that this component is rounded and fits into the engine snuggly.
I understand if you weren’t able to process any of that. You need to know what a crankshaft is and how it even gets damaged. Don’t worry, all of this important information is covered in this article.
What Is A Crankshaft?
First things first, you need to know what exactly a crankshaft is. In short, it is the component of your engine responsible for converting reciprocating linear motion to rotational motion. That may be a tad bit confusing for the unversed. Let me simplify things a bit.
The internal combustion engine is where all the reactions needed for your car’s movement happen. The energy generated in these combustions pushes your pistons in a linear direction.
The crankshaft takes the force from your pistons and changes the direction to follow a circular motion. This force is transferred to the transmission. The transmission then uses this force to rotate your wheels. As you can see, calling this part important is an understatement.
How Does A Crankshaft Work?
To serve its purpose, the crankshaft has several parts that need to work in harmony. The most important parts are:
- Main bearing journals
- Crankpins (AKA rods or connecting journals)
- Flywheel mounting flange
All these parts are constructed with high-strength steel. The main bearing journal connects it to the crankshaft. The crankpins form the rest of the structure with counterweights in between for rotation. The oilways allow proper lubrication. Finally, the flywheel mounting flange connects it to the flywheel.
Signs Of A Damaged Crankshaft
Before you go through the trouble to find a good mechanic to perform crankshaft grinding, you need to know if something is wrong with your crankshaft. These 3 telltale signs should instantly point to an issue.
1. Rattling Sound
Keep your ears peeled when starting the engine. If you hear a constant rumbling sound from your engine, you almost certainly have a bad crankshaft.
2. Stuttery Performance
If you find that your engine takes longer than usual to start or notice jittery performance on the road, you may need to check your crankshaft.
3. Check Engine Light
The CEL can be triggered by a multitude of issues. That’s why it is a good idea not to jump to the conclusion that your crankshaft is broken when you see this light. At the same time, you shouldn’t dismiss the possibility either.
Causes Of A Damaged Crankshaft
Once you know that something is wrong with your crankshaft, it is natural to be curious about why it happened. These 3 reasons are the most common culprits for a faulty crankshaft.
1. Excessive Torque
Are you someone who enjoys revving up their engine a bit too much? If that is the case, the amount of force you are putting on your crankshaft may just cause it to break. Not literally though, this part is strongly engineered.
2. Lack Of Lubrication
I cannot overstress the importance of adding enough engine oil. I’ve seen so many vehicles suffer from this issue. You can increase the lifespan of your engine greatly if you just follow this one rule: keep an eye on the engine oil level. If it drops too low, replenish your engine oil supply.
3. Wear And Tear
Unfortunately, no matter how careful you are with your engine, car parts do eventually succumb to wear and tear. Crankshafts last really long though so this is unlikely.
How To Repair A Faulty Crankshaft?
If you’re sure that your crankshaft is damaged and you know the source of the damage, there’s just one thing left to do: fix it. The best way to do that is crankshaft grinding.
Simply put, crankshaft grinding grinds and smoothens the main journals and crankpins on your crankshaft to a new lower OEM size. It chips away the outer layer so that the rods are a little smaller. It also polishes it to round it out. You need to put it back in place with new bearings.
This total rebuild ensures a tight fit with your bearings of choice. As it makes the rods slightly smaller, lubrication is improved as the oilways have less surface to spread the oil to. Best of all, it makes your crankshaft completely even, which leads to uniform rotations.
How Crankshaft Grinding Works
Back in the day, this was a long 25-step process that needed hours if not days of work from experienced mechanics. However, today, it takes 4 steps with CNC machinery in the picture.
The journals are grounded by either 0.005, 0.010, 0.020, or 0.030 inches to a minimum size of 0.050 inches. The reason for this is that there aren’t any bearings in the market that can lock in a main journal smaller than 0.050 inches.
Next, the journals are polished to remove any unevenness. This is done with emery paper or polishing belts. It is then locked in place with your new bearings.
Frequently Asked Questions (FAQs)
How Expensive Is Crankshaft Grinding?
You will need around $100 for the entire process. This price will vary greatly depending on the mechanic you are visiting, how much you need to grind away, and the model of your engine.
Can You Drive With A Faulty Crankshaft?
No. It is incredibly dangerous. One of the components that keep your wheels turning is now unreliable and so, you need to fix it as soon as possible. Also, if left ignored, there may be long-term damage to your vehicle.
Are There Any Alternatives To Crankshaft Grinding?
Unfortunately, the only alternative to crankshaft grinding is a complete replacement. This is much more expensive. The entire process will cost you over $2,000 with labor expenses. You better hope grinding works out.
Can I Do Crankshaft Grinding At Home?
Yes, you can. However, I highly doubt you would want to. Not only do you need a fair bit of expertise, but the machine is extremely expensive. The lowest price I found was around $20,000.
Can I Grind Any Crankshaft?
No. Some crankshafts are not built for grinding. The journals don’t have the thickness needed to be ground down to an OEM standard. If you are using a low-quality crankshaft, it simply isn’t strong enough for the process.
You now know the answer to the question: “What Is Crankshaft Grinding?” You should be proud of yourself as this is a highly complex procedure that even experienced mechanics struggle to understand fully.
Even though it won’t heal your crankshaft completely, it will delay an extremely expensive replacement. It is one of the best makeshift solutions in the automotive industry. However, you need to remember that this is not a permanent fix. Get your crankshaft replaced if it acts up again.