Tapping Aluminum Oil Pan: Expert Guide To Thread Chasing

Tapping an oil pan is the process of creating a small hole in the side of the pan above the oil line, and then using a tap to create threads to secure a hose barb fitting. This allows for the attachment of an oil drain line, which is used to lubricate and cool the engine and supercharger. While it can be intimidating and time-consuming, it is not a difficult process. One of the main concerns when tapping an oil pan is getting metal shavings into the motor, which can be mitigated by using grease when drilling and tapping.

Drilling and tapping an aluminium oil pan

If you decide to keep the oil pan attached to the engine, there are several precautions you can take to minimise the risk of metal shavings getting into the engine. One method is to use a vacuum or air hose to suck out or pressurise the crankcase, respectively, to prevent metal shavings from entering. You can also use grease to catch any particles before they can enter the pan. Dip the drill bit into lithium grease and drill for a few seconds, then wipe off the grease. Repeat this process until you have drilled the required depth.

Once you have decided on a method to deal with the metal shavings, you can begin the drilling and tapping process. Mark the target hole on the oil pan using the provided measurements from the instruction manual. Use a centre punch to punch a hole at the marked location. The depth of the hole will depend on the size of the required hole, so keep punching until the desired depth is achieved. Then, use a tap to create threads to seat the hose barb. The tap has four channels called flutes and four threaded sections. Pack the flutes with multi-purpose grease to catch any particles.

After tapping the hole, it is important to drain the oil and change it to flush out any particles that might have gotten into the oil. Then, connect the supercharger oil drain hose to the oil pan fitting and refill the oil to the manufacturer’s recommended level.

Using grease to prevent metal shavings

Tapping an aluminium oil pan can be a tricky process, and one of the main concerns is the risk of metal shavings getting into the motor. This can cause serious damage to the engine, so it is important to take steps to prevent this from happening. One effective method to prevent metal shavings from entering the oil pan is to use grease.

When drilling and tapping the oil pan, applying grease to the drill bit and tap can help catch the metal shavings and prevent them from falling into the pan. It is recommended to stop frequently during the process to clean the bit or tap and reapply grease. This method ensures that the shavings stick to the grease and can then be wiped away, reducing the risk of them entering the oil pan.

Additionally, using grease inside the bung or on the tip of the punch before tapping the pan can also help prevent metal shavings. This creates a smooth surface for the tap to cut into, reducing the amount of shavings produced and providing a barrier to catch any loose particles.

Another technique to further minimise the risk of metal shavings is to use a vacuum or shop vac to suck out the shavings as you drill. This can be done by placing a PVC pipe or a similar tool over the drill bit and attaching a vacuum to it. This setup will prevent the shavings from falling into the pan and will help collect them for safe disposal.

By combining these techniques, such as using grease and a vacuum, you can significantly reduce the risk of metal shavings entering the oil pan during the tapping process. It is important to be cautious and meticulous when performing these steps to ensure the safety and longevity of your engine.

Removing the oil pan

To remove the oil pan, first prop up the motor, drop the K-member, and then remove the oil pan. This process typically takes about 30 minutes with air tools, but it can be done in less than an hour by hand. It is also important to note that removing the AC unit may be necessary to access one of the motor mount bolts.

Another option for removing the oil pan is to leave the transmission bolted to the x-member and support the motor with a hoist. This method involves dropping the K-member bolts and sliding the oil pan out. This process is relatively simple and can be completed in about 30 minutes.

It is also possible to drill and tap the oil pan while it is still attached to the engine. This can be done by using a drill with a slow speed and dipping the drill bit into lithium grease or a similar substance. The drill bit should be wiped off frequently to prevent metal shavings from entering the oil pan.

Welding a bung onto the pan

Welding a bung onto an oil pan is a feasible option, but it should be done with care. The oil pan is made of cast aluminium, so it is essential to use the TIG welding method for a secure and safe weld. Other welding methods may be used, but only by seasoned professionals.

It is important to prepare the bung correctly. A ready-made aluminium bung may not retain its shape during the welding process, so an alternative method is to cut a 3/8" wafer from 1" round stock. A 3/4" pan work hole should be drilled, with the bung placed on the outside of the pan. The weld can then be performed from the inside, with an additional bead around the outside. The bung can then be drilled and pipe-tapped.

There are other methods to consider. A compression fitting could be mounted through a hole drilled in the pan, but there is a risk of warping. Alternatively, a nut can be welded to the inside or outside of the pan, with a matching bolt and copper washer used to seal. If the nut is welded to the outside, more fluid can be drained, but there is a risk of leaks, and the weld will be more exposed. A thick pan can accommodate an internal nut with a wide shoulder, providing a large surface area for the weld, and allowing most fluid to escape.

Using a vacuum to remove metal shavings

Tapping an aluminium oil pan can be a tricky process, and one of the main concerns is the presence of metal shavings in the motor. To mitigate this, you can use a vacuum to remove metal shavings while drilling. Here is a step-by-step guide on how to effectively use a vacuum for this purpose:

Prepare the Work Area:

Before you begin, ensure you have a suitable work area with enough space to work comfortably. Gather all the necessary tools and safety equipment, including eye protection, gloves, and a respirator. Place a drop cloth or cardboard underneath the oil pan to catch any spills or debris.

Choose the Right Vacuum:

Select an industrial vacuum cleaner designed for recovering metal shavings and oils. Look for features such as a large tank capacity, the ability to vacuum both liquids and solids, and an efficient filtration system to separate metal shavings from oil. The EMULSIO vacuum cleaner, for example, is designed for machine shops and has these features.

Set Up the Vacuum:

Position the vacuum close to the work area, ensuring that the hose can reach the oil pan comfortably. Attach any necessary attachments or extensions to the hose to improve manoeuvrability and reach tight spaces. Ensure the vacuum bag or container is empty and ready to collect the metal shavings.

Start Drilling:

With the vacuum running, begin the drilling process. Go slow and use a drill bit dipped in lithium grease to minimise the creation of metal shavings. Stop frequently to wipe off the grease and check the progress. This will help prevent the build-up of metal shavings and reduce the risk of them falling into the oil pan.

Use the Vacuum:

As you drill, use the vacuum hose to suction up any metal shavings that are created. Move the hose around the drilling area to ensure all shavings are captured. The vacuum will separate the metal shavings from the oil, allowing for easy disposal of the shavings and the safe recovery of the oil.

Clean and Inspect:

Once the drilling is complete, thoroughly clean the area, ensuring no metal shavings are left behind. Inspect the oil pan for any signs of damage or debris. If necessary, change the oil and use a magnetic drain plug to capture any remaining metal particles.

By following these steps and using a vacuum to remove metal shavings, you can effectively tap an aluminium oil pan while minimising the risk of contamination and damage to your engine. Remember to work slowly, be cautious, and always put safety first.

Frequently asked questions