Can head bolts be reused?

Can You Reuse Head Bolts?

As I’ve spent too many hours under the hood of my various rides, it was inevitable that I would eventually wonder if head bolts can be reused. After doing some more digging, I came up with the answer to this question, and gained some valuable information on the topic along with it.

Can you reuse head bolts? Although it is not necessarily recommended by the manufacturer to reuse head bolts in your car, it can be done. As long as the bolts are in good condition and you follow a few safety tips, you should be able to use them multiple times.

If you have ever done work on the engine of a car, then you have probably come in contact with head bolts at some point. Based on the fact that they can come in different shapes and sizes that will fit particular automobiles, you might have wondered if you could just reuse the ones you have.

Take a look at this quick guide to find out everything you need to know about reusing head bolts and the best way to do so.

Can You Reuse Head Bolts?

Head bolts are an important feature of every automobile engine, keeping everything tightly secured in place and preventing any accidents from the inside of the car.

More specifically, the head bolts hold a piece of the engine together called the head gasket, which is a vital piece of the engine.

Head Bolts:

  • Made of stainless steel
  • Strong and elastic
  • Various sizes and shapes

When your car reaches a certain amount of miles or your head gasket blows, whichever one comes first, you will likely need to replace the head bolts along with it.

However, most people would be surprised to learn that you can actually reuse head bolts during this process. It is not the best practice, but it can work when you are in a tricky situation.

The list below will indicate when it is okay to use the same head bolts again when you are replacing other components of your car’s engine.

When Head Bolts Can Be Reused:

  • Good condition
  • Fairly new
  • Properly prepared for re-use

First and foremost, if the quality and condition of your current head bolts are relatively quality and somewhat new, it will be safe to use them again. In other words, if your head bolts look and feel good, you should have no problem re-installing the same ones.

Additionally, if you know that you have just recently purchased your head bolts and they are still fairly new, this should translate to the bolts being in good condition as well.

Whenever you remove your head bolts from the engine of the car, you will need to inspect them for all of these potential issues, as well as clean the surface to prepare it for re-installation.

The steps of preparing your head bolts for re-use will be described in more detail in the next section, along with some valuable safety tips that should be used before you implement old head bolts back into your engine.

Safety Tips for Reusing Head Bolts

While it is not recommended by automobile manufacturers to reuse old head bolts, it absolutely can be done when necessary. However, if you decide to take this risk, there are a few safety tips that you should adhere to for the best results.

The list below will give you a short outline of how you should go about reusing your head bolts, and the rest of this section will give you more details on how to successfully complete this task.

Tips for Reusing Head Bolts:

  • Clean the bolts
  • Inspect them for damages
  • Soak in oil
  • Clean the thread holes
  • Use a torque wrench
  • Stay away from bolt adhesives

The first thing you should do before reusing a head bolt is to clean it. They must be cleaned due to the fact that they will experience high levels of heat within the engine of the car. While cleaning them, they should also be inspected for cracks and other damages to the surface.

After they have been properly cleaned and inspected, you will want to soak them in motor oil. They should be completely submerged in the liquid for at least 24 hours, in order for the oil to sink into every area of the bolt.

Next, the thread holes of the bolt will need some individual attention. Using a tap and die set, you will need to clear out the bolt holes’ threads that are located within the heads. Before you begin this step, you will need to make sure the tap matches the bolts in size without causing any damage to the threads.

Finally, you will want to use a torque wrench to re-install the head bolts to get the quickest, easiest, and smoothest results when you have finished.

The process of tightening these bolts back into the engine will require setting them with a regular socket wrench, and then finishing off the process with a stronger torque wrench.

The last safety tip to remember when reusing head bolts is to stay away from bolt adhesives at all cost. Loctite and other similar products will be harmful to the engine and cause a lot of safety issues in the future.

When to Replace Head Bolts Instead of Reusing Them

While it is true that head bolts can be reused multiple times if they are in the right condition, there are certain circumstances in which you will need to fully replace the head bolts with new ones.

These reasons are outlined in the list below, and described in more detail throughout the rest of this section.

When Head Bolts Should Be Replaced:

  • Bolts are not in good condition
  • Bolts become resistant

The first, and most obvious, reason why head bolts would need to be replaced instead of reused would be a decline in quality and condition. If the bolts are visibly damaged in any way, you will not be able to use the same ones again.

A good way to test the quality of your head bolts before using them again is to put some motor oil on the outside and try to screw them in using just your hand.

If the head bolt is able to be screwed in smoothly and easily with the use of just your fingers, you will most likely be able to install it back into your engine.

However, if the bolt displays any kind of resistance or gets stuck in doing this, it will tell you that it needs a full replacement. In the most ideal situation, you should be able to almost secure the entire thing by twisting it with your fingers.

In general, if you complete the steps of cleaning and inspecting your head bolts and something looks off, you should never put them back into your engine.

When Should I Check My Head Bolts To Replace Them?

When Head Bolts Should Be Checked:

  • Every 200,000 miles
  • When head gasket is blown

In addition to the reasons why head bolts should be completely replaced instead of reused in some situations, you should also know when you should check them in the first place.

While there is no specific time frame in which you should check and replace head bolts in your automobile engine, you can follow the guidelines of the head gasket of the car.

Generally, you will want to check this every 200,000 miles that you have driven your car. Before this point, you shouldn’t have any issues, unless there is a direct problem with the gasket.

With that being said, if your head gasket is leaking or has blown completely, you will want to check your head bolts for quality and see if you might need to replace them.

Related Questions

Can you still drive a car with a blown head gasket?

If you are aware that the head gasket has been blown or damaged within the engine of your car, the problem should be fixed before you continue driving. This is due to the fact that leaking coolant and other gases from the engine can cause the area to crack and erode.

Is it difficult to replace a head gasket?

The task of replacing a head gasket is a very complicated process, and should be left to professional mechanics only. With so many complex steps involved in the replacement, you are likely to make a mistake somewhere if you do not have the proper training. So, if your head gasket ever needs replacement, you should pass it off.

Do head bolts need washers?

When head bolts are installed into any engine, washers are required to be placed directly under the heads. If the washers are not present during the installation, the head of the bolt is more likely to cut into the aluminum that is directly underneath it. This will cause problems with the torque of the bolt being uneven within the car’s engine.