Removing A Broken Bolt: Transmission Pan Edition

Removing a broken bolt from your transmission pan can be a tricky task. There are several methods you can try, such as using a reversible drill, a screw extractor, left-handed drill bits, or a combination wrench. Some people have suggested using superglue or epoxy to temporarily fix the broken bolt, but this may not be a long-lasting solution. It's important to note that attempting to remove the broken bolt yourself may result in further damage to the pan or gasket, so it might be worth considering getting a professional to do the job for you.

Using a reversible drill and a screw extractor

Firstly, you need to mark the centre of the bolt. You can use an awl for this, and then use a centre drill or a countersink to make a small centre hole. It is important to note that the centre drill and countersink are different tools, so ensure you have the correct one.

Next, you can use your reversible drill as an extracting drill. If your drill is too large, you may need to use a smaller one to fit into the compartment. You can then use your extracting drill bit, which will be either a left-handed drill or a screw extractor.

If you are using a left-handed drill, you will need to use vice grips or the proper tap/die tool to back the bolt out. This process should be done slowly and steadily to ensure you do not cause further damage.

It is also worth noting that if you do not have access to a hoist, you will need a right-angled drill to get into the correct position and angle for drilling.

Using left-handed drill bits

To use a left-handed drill bit, start by ensuring the bolt is as flat as possible. File or grind the bolt if necessary. Once the bolt is flat, use a centre punch to mark the centre of the bolt, and drill a small centre hole with a centre drill.

Next, put the left-handed drill bit into the chuck of the drill and drill the hole in reverse. If the drill bit bites into the bolt, it will extract the screw and remove it from the hole. If it does not remove the damaged bolt, you can use a screw extractor or easy out.

It is important to note that left-handed drill bits are most useful when the broken bolt is in a blind hole (a hole that does not go all the way through the material). If the broken bolt goes through the hole in the material, a right-handed drill bit can be used to drill out the broken part.

Welding a nut on top

To begin, select a nut with an inner diameter roughly matching the size of the stuck threaded bolt. Place the nut on the bolt and weld the inside of the nut to the broken top of the bolt. It is important to ensure that the weld adequately penetrates the broken bolt. Use a wrench to remove the nut and bolt together. For added strength, you may need to weld a washer to the bolt first and then weld the nut to the washer.

It may take several attempts to successfully remove stubborn bolts. Drilling into the bolt can provide more surface area for the weld to adhere to and increase the chances of success. Additionally, soaking the bolt with a penetrating agent, such as PB Blaster, before welding may be sufficient to free the bolt without the need for welding.

Drilling halfway through the bolt and using a reverse thread extractor bit

First, you'll need to mark the centre of the broken bolt. Use an awl or a centre punch to create a small indentation at the centre of the bolt. This will help ensure that your drilling is accurate and centred. Once you've marked the centre, select a drill bit that is slightly smaller than the size of the broken bolt. You want to drill halfway through the bolt, so adjust the depth of your drill accordingly. Secure the drill bit in the drill and position it straight over the broken bolt. Start drilling slowly and with moderate pressure to maintain control. Use a steady hand and go slow to avoid slipping and damaging the transmission pan. Once you've reached halfway through the bolt, stop drilling and remove the drill bit.

Now, it's time to use the reverse thread extractor bit. Select a reverse thread extractor bit that matches the size of the broken bolt. Position the extractor bit into the hole you drilled, and use a hammer to gently tap it into the bolt. Make sure the extractor bit is securely seated in the bolt before proceeding. Once the extractor bit is in place, use a wrench or vice grips to turn the extractor bit counter-clockwise. This will help loosen the broken bolt. Turn the wrench or vice grips slowly and with controlled force to avoid breaking the extractor bit. As the bolt starts to loosen, continue turning the extractor bit until the bolt is completely removed.

It is important to note that this method requires some mechanical skill and the right tools. If you are not confident in your ability to perform this task, it may be best to consult a professional mechanic. Additionally, always wear appropriate safety gear, including eye protection and gloves, when attempting to remove broken bolts.

Using penetrating fluid

If you're trying to remove a broken bolt from your transmission pan, one method you can try is using penetrating fluid. This fluid is designed to loosen stuck or frozen bolts by penetrating the thread and breaking down rust and corrosion. Here's a step-by-step guide on how to use penetrating fluid effectively:

Step 1: Apply Penetrating Fluid

Locate the broken bolt on your transmission pan and apply a generous amount of penetrating fluid to the bolt and the surrounding area. Make sure the fluid comes into contact with the thread of the bolt. Allow the fluid to soak for several hours or, ideally, overnight. The fluid will start to break down any rust or corrosion that is holding the bolt in place.

Step 2: Attempt to Remove the Bolt

After allowing the penetrating fluid to soak, try to remove the bolt using the appropriate tool, such as a wrench or socket. It may also help to apply heat to the case and/or cool the bolt using a torch and ice spray. This temperature difference can help loosen the bolt. Be cautious when applying heat, especially if there is flammable oil in the transmission pan.

Step 3: Repeat as Needed

If the bolt still doesn't budge, repeat the process by applying more penetrating fluid and allowing it to soak again. You may need to repeat this step several times for the fluid to fully penetrate and loosen the bolt.

Step 4: Consider Other Methods

If penetrating fluid alone is not effective, you may need to combine it with other methods. One suggestion is to use a long handle to try and break the bolt free. Alternatively, consider drilling out the bolt and then repairing the thread. This will involve drilling the broken bolt out, re-threading the housing, and using a new bolt.

Frequently asked questions