Turbocharged Engines Need Special Oil Pans: Why?

Turbochargers are used to enhance an engine's performance and optimise combustion. The core of the turbocharger is the rotating assembly, consisting of the turbine wheel with shaft and impeller. The turbine wheel is located on the exhaust side and is connected to the shaft, with the impeller mounted on the other end. The exhaust flow from the engine is directed through the turbine, which leads to a rapid rotational movement of the turbine wheel, subsequently driving the impeller. The turbine speed depends on the design and exhaust volume. In small turbochargers, the rotating assembly reaches speeds of up to 300,000 RPM.

Inadequate lubrication is one of the most frequent causes of turbochargers failing. If the turbocharger is not sufficiently supplied with oil, its very high speeds will cause damage within a short time. This can lead to issues such as the impeller and turbine wheel striking the turbocharger housing, the turbocharger boost pressure being too low, the exhaust system emitting black smoke, and the shaft shank exhibiting clear discoloration.

To avoid these issues, it is important to ensure that the turbocharger is properly lubricated and cooled. This can be achieved by using the correct type of oil, changing the oil regularly, and ensuring that the oil level in the engine is not too low. Additionally, it is important to avoid operating the engine with biodiesel or vegetable oil, as this can cause the engine oil to gel. By taking these precautions, you can help ensure that your turbocharger remains in good working condition.

Drilling and tapping the oil pan while it's on the car

Drilling and tapping the oil pan while it's still on the car is possible but not recommended. The main reason for drilling and tapping the oil pan is to install a fitting for the oil return line of a turbocharger. While it is possible to do this with the oil pan on the car, it is much easier to access the factory location to drill and tap the hole with the oil pan removed.

If you choose to drill and tap the oil pan while it's still on the car, there are a few things you should keep in mind. First, make sure you have the correct size drill bit and tap. For a 1/2" NPT tap, a 45/64" or 23/32" drill bit is typically used. You should also use plenty of grease on the tip of the drill bit and tap to help catch any metal shavings and reduce the risk of contamination. Take your time and go slow when drilling and tapping to avoid making the hole too big or damaging the oil pan.

Once you've drilled and tapped the hole, you'll need to clean out any metal shavings that may be inside the oil pan. One way to do this is to overfill the engine with oil before drilling, as the oil will help carry the shavings out into your oil bucket when you punch through the pan. You can also use a garden hose to run water through the pan, letting it trickle through to flush out any remaining shavings. Be sure to change the oil several times after drilling and tapping to remove any residual shavings.

In addition to the drilling and tapping, you'll need to lower the oil pan slightly to access the factory location. To do this, you'll need to raise the car and support it safely on jack stands. Drain the oil and remove the front wheels. Detach the brake line brackets from the side of the front subframe, then remove the nut from the long bolt in each motor mount. Place a floor jack under the oil pan with a block of wood to protect it, and lift just enough to take the stress off the motor mounts. Remove the motor mount bolts and support the motor with a jack stand under the crankshaft pulley. At this point, you should be able to lower the oil pan slightly and access the factory location for drilling and tapping.

While it is possible to drill and tap the oil pan while it's still on the car, it is a more difficult and risky process. It's important to take your time and follow the proper procedures to avoid damaging your engine or turbocharger.

Avoiding metal shavings getting into the oil pan

Metal shavings in the oil pan can cause serious damage to your engine. The oil in your vehicle passes through and around a lot of moving parts. Given the speed of these moving parts and the amount you use your engine, some metal is bound to slowly chip off over time. This is a part of normal engine wear.

The oil filter is responsible for catching metal flakes. This is why it’s key to check and replace the oil and the oil filter on a regular basis. However, the oil filter can't catch them all, so it's important to regularly replace the oil and oil filter to reduce the risk of metal flakes building up and causing issues for your engine.

Some signs of metal shavings in your oil include reduced engine power, ticking noises, rough idles, engine knocking, and white exhaust fumes.

If you discover metal shavings in your oil, it's important to take your car to a repair shop immediately. They will be able to diagnose the issue and perform any necessary repairs.

Using grease and drilling in small increments

Drilling into your oil pan can be a daunting task, but with the right tools and precautions, it is a manageable process. Here is a step-by-step guide to help you drill your oil pan safely and effectively:

Step 1: Gather Tools and Materials

Before you begin, make sure you have the necessary tools and materials:

• Sturdy jack stands and an extra tire for safety
• Drill with a 1/2" drive (or a borrowed one if you don't have that size)
• Tap wrench—a 3/8 NPT tap fits a 5/8" 12-point socket, and 16mm should also work
• Electrical tape to act as a bumper and prevent over-drilling
• A smaller bit for a pilot hole, such as a 1/4" bit, or a center punch to locate the large drill bit
• Grease—lots of it, like black moly grease
• Paper towels
• Q-tips (optional but helpful for cleaning)
• Mineral spirits for flushing the pan
• Thread sealant or JB Weld for installing the fitting

Step 2: Prepare the Work Area

Locate your oil pan and ensure your car is securely lifted, ideally using jack stands. Give the car a good shake to ensure stability, and place an extra tire underneath for added safety.

Step 3: Determine the Drilling Location

Different turbo kits will specify different locations for the hole. Generally, you should drill as far forward on the pan as possible, avoiding the AC compressor bracket. Aim for the highest point without interfering with other components.

Step 4: Drill a Pilot Hole

Use a smaller drill bit or a center punch to create a pilot hole that will guide your larger drill bit. Grease the drill bit to manage the shavings, and drill slowly and carefully. Stop to re-grease the bit often. You don't need to drill all the way through; just create a decent pilot hole.

Step 5: Drill the Main Hole

Now it's time to drill the actual hole. Use the large drill bit (37/64ths) and drill with confidence but also with caution. Take your time, and use grease and paper towels to manage the metal shavings. Remember to use the electrical tape as a bumper to prevent drilling too far and damaging the oil pickup. Drill until you have a clean hole, then clean up the edges as best you can.

Step 6: Tap the Hole

Apply grease to the tap, and begin tapping the hole. If your engine is mounted in a car, you'll likely have to drill at an angle, but try to tap the hole straight. Cut a few turns, then remove the tap, clean it, and re-grease before continuing. Leave only 2-3 threads of the tap visible outside the pan to maintain a safe distance from the oil pickup.

Step 7: Clean and Install the Fitting

Use a Q-tip or your finger, dipped in grease, to fish out any remaining shavings from the hole. Flush the pan with mineral spirits to ensure it's clean. Before applying JB Weld or thread sealant, thread the fitting into the pan to ensure it fits. Then, apply the sealant or JB Weld to install the fitting.

And that's it! You've successfully drilled and tapped your oil pan. Remember to take your time, use grease liberally, and drill and tap in small increments to avoid mistakes.

Welding a fitting to the oil pan

Before welding, it's crucial to thoroughly clean the oil pan to remove any oil residue. You can use a wire wheel on an angle grinder and solvents like acetone to get it clean. Preheating the oil pan to around 300°F can also help cook out any remaining oil and reduce the risk of hydrogen precipitation, which can lead to brittle welds.

When choosing a welding rod, ER70S2 or 309 are commonly used for steel oil pans. If you're concerned about porosity, you might consider using 70S6 or brazing rod. For aluminium pans, you'll need to use aluminium TIG welding techniques and ensure you have good gas coverage to prevent oxidation.

Finally, it's important to test the oil pan for leaks after welding. Fill the pan with oil and check for any leaks, especially around the weld joint and threads. If there are leaks, you may need to grind out the weld and start over or use a sealant like JB Weld or Teflon tape as a temporary solution.

Using a step bit to avoid creating more shavings

A step drill bit is a versatile tool that can be used to drill accurate holes in metal, wood, and plastic. It is particularly useful when drilling through thick materials, as it has a built-in stop that prevents the bit from slipping and allows you to work continuously without having to reset.

When using a step drill bit, it is important to take safety precautions. Wear protective gear such as goggles and gloves, and use a step drill guide attachment to prevent slipping and ensure accuracy. Mark the hole sizes on the bit to know where to start and stop drilling. Drill at a 90-degree angle to the chosen starting point, and avoid forcing the drill into the material, as this can cause breakage and flying debris.

To avoid creating more shavings when using a step drill bit, follow these tips:

• Use the correct direction of rotation: The flutes on the step drill bit are designed to force shavings out of your way. When drilling into wood or metal, use a clockwise step drill bit to prevent debris from getting into your hand.
• Be mindful of your speed: Work at a slow, steady pace, especially when drilling into metal or wood. Consider the hardness of the material and its effects on the bit.
• Be aware of the shavings: Sweep away any shavings that may become problematic, as more shavings will result in a messier drilling process.
• Use a lubricant: A step drill bit will heat up as you drill, so apply a lubricant to keep it cool and prevent excessive amounts from getting on your hands.
• Align the drill bit: Before starting, align the drill bit with the desired piercing point to avoid drilling at an angle, which can cause a mess and increase drilling time.

By following these instructions and tips, you can effectively use a step drill bit to create clean and accurate holes while minimising the amount of shavings produced.

Frequently asked questions