Measuring Oil Pan Depth: A Step-By-Step Guide

Measuring oil pan depth is a critical step in engine building, as it ensures sufficient clearance and oil pressure during engine operation. There are several methods to determine oil pan depth, which can be done with the pan on or off the car. One common approach is to use a straight edge and a measuring tape. The straight edge is placed across the pan rails, and measurements are taken from the straight edge to the block rail and the bottom of the pan. Another method involves using modelling clay to measure the clearance between the oil pump and the oil pan. A thin piece of tape is applied to the pickup to prevent clay from getting into the engine, and the pan is then bolted on. The thickness of the clay is measured after removing the pan.

Using a straight edge and tape measure

To measure the depth of an oil pan using a straight edge and a tape measure, follow these steps:

First, place the straight edge on the inside of the oil pan, ensuring that one end is flush with the top edge of the pan. This will serve as a reference point for your measurement. Hold the straight edge steady and perpendicular to the pan to ensure accuracy.

Next, take the tape measure and place it vertically inside the pan, starting from the reference point you just created. Let the tape measure reach the bottom of the pan, and then take note of the measurement where the tape meets the straight edge. This will give you the depth of the oil pan.

Make sure the tape measure is straight and not bent or curved during this process, as it will affect the accuracy of your reading. It is also important to use a tape measure with clear markings and a straight edge.

Additionally, you can measure the depth of the oil pan from the outside if needed. Place the straight edge across the top edge of the pan, ensuring it is flush with the pan's opening. Then, hold the straight edge steady and place the tape measure vertically outside the pan, starting from the reference point. Take note of the measurement where the tape meets the straight edge, and this will give you the depth of the oil pan from the outside.

These methods can be applied to various containers, such as frying pans or pie pans, by following the same principles of measuring the distance from the top edge of the container to the bottom using a straight edge and a tape measure.

Oil pump and oil pan clearance

Measuring the oil pan depth and ensuring the proper clearance between the oil pump and oil pan is crucial for the optimal performance of your engine. Here are some detailed instructions and tips for achieving the correct oil pump and oil pan clearance:

Measuring Oil Pan Depth:

• On the Car Method: Place a straight edge on the bottom of your oil pan, extending it past the sides. Using a measuring tape, measure upwards from the straight edge to the pan rail near the third bolt from the front. Report your findings accurately, rounding to the nearest 1/8".
• Off the Car Method: Lay a straight edge across the pan rails at the third bolt hole from the front. Measure downwards from the straight edge to the bottom of the pan. Again, ensure you report your findings to the nearest 1/8".
• It is essential to measure the clearance between the oil pump and the oil pan to ensure sufficient oil pressure during engine operation. This measurement is critical and can significantly impact your engine's performance.
• The recommended clearance between the oil pump and oil pan varies depending on the type of engine. For Ford and Chevy pans, a clearance of 5/16" to 3/8" (0.312" to 0.375") is suggested. For other engines, a similar clearance of 5/16" to 3/8" is recommended.
• Deep sump pans with pickups submerged deeper into the oil are less sensitive to clearances. In such cases, a clearance of up to 1/2" is acceptable.
• To measure the clearance, you can use methods suggested by companies like Moroso. One simple method involves dry-fitting the pan to the engine using clay and tape to prevent the clay from getting into the pickup. After bolting the pan, remove it and check the clay's thickness with calipers.
• Another method involves using a straightedge and a tape measure. Measure the distance from the straightedge laid on the pickup screen to the block rail on both sides. Then, measure the depth of the sump in the pan by laying the straightedge across the rear of the pan.
• Adjust the oil pump pickup as needed to achieve an even clearance within the recommended range.
• If your oil pump pickup is welded to the pump, you may need to bend it slightly to gain the desired clearance. Ensure any modifications do not affect the integrity of the pickup or its attachment to the pump.
• If your oil pan has a windage tray, ensure the oil level is below the tray when measuring and adjusting the clearance.
• Always refer to the manufacturer's instructions and recommendations for your specific oil pan and pump setup.

Measure from the pickup to the pan

Measuring the clearance between the oil pump and oil pan is critical to ensuring your engine runs smoothly. Here are four methods to measure the depth from the pickup to the pan:

Method 1: Using Clay

This method involves using clay to measure the clearance. First, place a piece of oil-based modelling clay on the pickup, forming a cone shape with one end flat. Oil the point of the clay to prevent it from sticking to the bottom of the pan. Next, dry-fit the pan to the engine, bolting it on at the four corners. Finally, remove the pan and measure the height of the clay cone to determine the clearance.

Method 2: Straightedge and Tape Measure

For this method, you will need a straightedge and a tape measure. Lay the straightedge on the pickup screen and measure both sides in relation to the block rail. Then, place the straightedge across the rear of the pan and measure the depth of the sump. These measurements will help determine the clearance and ensure sufficient oil pressure during engine operation.

Method 3: Measuring Pan Depth on the Car

Place a straight edge on the bottom of your oil pan, extending it past the sides. Measure up from the straight edge to the pan rail near the third bolt from the front. Ensure you report your findings accurately to the nearest 1/8".

Method 4: Measuring Pan Depth off the Car

Lay a straight edge across the pan rails at the third bolt hole from the front. Measure down from it to the bottom of the pan. Again, accuracy is important, so report your findings to the nearest 1/8".

Remember, the ideal clearance between the pickup and the pan is around 3/8" to 1/2". Too little clearance can restrict oil flow, while too much clearance may result in insufficient oil reaching the pickup.

Pan on or off the car

Measuring the depth of your oil pan can be done with the pan on or off the car. Here are the steps for both methods:

Measuring Pan Depth on the Car:

• Place a straight edge on the bottom of your oil pan, extending it out past the sides.
• Measure upwards from the straight edge to the pan rail, near the third bolt back from the front.
• Report your findings to the nearest 1/8 of an inch.

Measuring Pan Depth off the Car:

• Lay a straight edge across the pan rails at the third bolt hole back from the front.
• Measure downwards from the straight edge to the bottom of the pan.
• Report your findings to the nearest 1/8 of an inch.

It is important to ensure that you have the correct clearance between the oil pump and the oil pan to maintain sufficient oil pressure and avoid engine failure. Always follow the recommended clearance specifications for your vehicle.

Using clay to measure clearance

Measuring the clearance between the oil pump and oil pan is critical to ensure sufficient clearance and oil pressure while the engine is in operation. One of the methods to do this is by using clay.

First, before sticking the clay on the pickup, cover the pickup with a thin piece of racer's tape to prevent any of the clay from getting squeezed into the pickup and subsequently into the engine. Then, place a small amount of clay on the pickup. Next, bolt the pan on and snug it up at all four corners. After that, remove the pan and check the clay’s thickness with a pair of calipers. You can also try removing the gasket from the equation to test how much clearance is present using the one-piece gasket in case you need more or less clearance.

Another method is to use a straightedge and a tape measure. Lay the straightedge on the pickup screen and measure at both sides of the straightedge in relation to the block rail. Then, lay the straightedge across the rear of the pan and measure the depth of the sump in the pan using the tape. Finally, measure the gasket that will be used in combination with the pan to determine the total dimension you have to work with in the application.

The recommended clearance between the pickup tube and the oil pan is around 3/8".

Frequently asked questions