So you discovered there’s a broken bolt inside your car engine block, and you’re looking for the best way to remove and replace it? Here’s a comprehensive guide on how to remove a broken bolt from an engine block.
You may accidentally break a bolt while trying to fasten or loosen an engine component, and once a bolt is broken, it becomes difficult to remove. However, there are a few not-too-easy tricks you can practice to remove the bolt.
Basically, the process involves drilling down the bolt and using an extractor bit to remove the bolt without messing with the threads. Removing a broken bolt can be done by individuals, but it’s best to have an experienced mechanic handle the job since it has to do with the engine block.
How To Remove A Broken Bolt From An Engine Block
There are a couple of ways to go about this, but majorly to drill down and extract the bolt using some specific hand or power tools.
For this method, you’d need a center punch, eye protector, file, gloves, drill/extractor set, lubricant (WD40), and a hammer. With these items, you can proceed with the steps below.
Use the filing tool you got to smoothen the surface of the broken bolt; it has to be even before you can proceed further. After smoothening the surface, get your center punch and hammer and create a mark on the center of the broken bolt. Make sure the mark is inflicted on the center of the bolt – this is very important.
Get your drilling tool and drill the center of the bolt; make sure the drilling tip is well placed at the center of the broken bolt – where you made the mark – and then drill carefully.
You should use a sturdy drill tool to avoid the tool breaking off during the drilling process. Remember to put on your eyewear to protect your eye from debris.
After the drilling, get your extractor kit and place the main extractor tool into the hole you just drilled – you may need to lubricate the hole so the extractor can penetrate easily.
Typically, bolt extractors are threaded anticlockwise, so when you fit in the extractor, you should use a spanner or a tap & die tool included in the set to rotate the extractor and remove the broken nut.
This method has worked for quite a lot of people, and it’s pretty easy when you’ve got all the required tools handy. Also, you may need to use a magnet to remove the metal shavings around the drilled area so they don’t get carried into the engine when the oil flows.
Second Method: Welding the Broken Bolt
If you know pretty much about metal welding and heat transfer processes, this may appear as the perfect method for you to remove broken bolts from engine blocks. For this method, you’d need a wrench, eyewear, MIG or TIG welder, a nut, and a flat washer.
Firstly, you need to thoroughly clean the surface of the broken bolt and its surroundings; this will help the welding to be more effective. After cleaning the surface, get a washer and nut with the same inside diameter as the stuck bolt.
Carefully place the washer and nut on the stuck bolt and start welding from the inside. This will force the stuck bolt to join with the nut, and that makes it quite easy to remove the bolt using a wrench or sizeable spanner.
Use the wrench you’ve got and turn the nut anticlockwise; this will also move the nut anticlockwise and loosen it from its stuck position, then you can finally remove the nut. The welding approach is the most cost-effective method, but it requires top-level expertise too.
Frequently Asked Questions
What Kind Of Drill Bits Go Through Metal?
There are quite different sturdy drill bits, but the Cobalt drill bits are typically exceptional for drilling through metals. You can use the Cobalt drill bits to drill through and remove stubborn broken bolts from engine blocks.
How Do You Remove A Broken Bolt Without An Extractor?
You can use tapered screws threaded anticlockwise or practice the welding method of removing broken bolts. However, the use of extractor bits is the preferred method for most DIYers faced with a broken bolt situation.
How Do You Remove A Bolt With The Head Snapped Off?
You either weld a nut to the bolt and then remove the bolt by rotating the welded nut or drill through the bolt and use an extractor bit to pull it off. Either way, removing a stuck bolt can be quite a stressful job, and you should wear all the necessary protective gear.
These are the two surest methods on how to remove a broken bolt from an engine block. Always remember to wear a helmet or, at least, eyewear to protect your eye while trying out any of these methods.
Also, ensure to put on all necessary protective gear with respect to each of the methods above. If this looks too technical for you to handle, you can call on a mechanic or a professional automotive technician to do it for you.