Did your spark plug hole threads get stripped? Don’t worry, we’ll help you repair that easily.
It is not uncommon for your car’s spark plug hole threads to get stripped. When the spark plug hole has been attached to the cylinder head for too long without changing them, the aluminum thread may get stripped off. This usually happens over time as your car’s spark plug hole’s health starts to deteriorate. No matter whatsoever, the reason might be, we have a fix for that. You can easily rethread a spark plug hole, but you might need a professional’s help if you’re not familiar with the process of how an engine works.
But if you’re looking for a quick fix for your stripped spark plug hole or for how to rethread the same, then read ahead and learn how to repair it with minimal efforts.
How to Rethread a Spark Plug Hole
There are a few ways to rethread a spark plug hole, and one of the most commonly used is to insert a Helicoil. You can also try to track the old threads by purchasing a ‘thread chaser’ tap of the correct size, wash them off properly, and you’ll be good to go. But this will only work if the threads aren’t damaged extensively. If the thread has been damaged too badly, you’ll need to remove the cylinder head. A proper thread repair can last for a very long period of time.
STEP 1: Start from the Basics
The first thing you’ll need to do to repair your spark plug hole is to buy a thread repair kit or insert kit and simply install it into the spark plug hole. Thread repair kits are very easily found in auto stores, or you can easily buy them off of amazon. These kits usually consist of thin wall inserts, a drill, a tap, and an installation tool. Everything you’ll need to fix your spark plug hole.
STEP 2: A long way to go
Start by removing the spark plug so you can see the stripped threads in the hole. First of all, clean the damaged threads with the help of the tapping tool. To avoid getting aluminum chips and to catch all the shavings while re-tapping the threads, grease the tap. Greasing is necessary because if the aluminum chips get inside the engine, it can harm it.
Now, stick the tap inside the hole and turn it to start cutting the new threads and turn it slowly and smoothly to cut the threads as you don’t want to break anything inside the hole. While cutting the new threads, use the old damaged ones as a guide to get the correct alignment for placing the threads back. As you thread the tap into the spark plug hole, cut oversized threads and tighten the tap in the remains of your old spark plug threads.
Make sure that the new threads are parallel to the old damaged ones. It is essential to place your new threads properly over your old ones or a few of the remaining good ones for the spark plug to fit properly into the hole. Now take out the tap after you have threaded till the bottom, which is equivalent to the place where the old threads used to be inside the hole.
STEP 3: Some final touch
The last step is to screw the thread insert onto the installation mandrel and then tighten it. Now use the installation mandrel, which comes along with the recoil kit and insert the new oversized threads into the spark plug hole. Please take out the installation tool from the hole and clean it. Lastly, put the spark plug back into its place. And it’s done. You have finally accomplished this tedious task. Repairing a spark plug is not very simple but following these steps, you can easily rethread a spark plug hole.
Bottom Line:
Remember, this may seem simple and doable, but if you have no experience whatsoever, it’s best to go to your mechanic and let him do the work for you. Experts can help you professionally and easily rethread a spark plug hole. You must make sure that your engine is healthy and so are the plugs. Follow the simple steps and you can rethread your plugs.