Oil Leak Diagnosis
Oil Leak Diagnosis

Step

Action

Yes

No

Note: You can repair most fluid leaks by first visually locating the leak, repairing or replacing the component, or by resealing the gasket surface. Once the leak is identified, determine the cause of the leak. Repair the cause of the leak as well as the leak itself.

1

  1. Operate the vehicle until it reaches normal operating temperature.
  2. Park the vehicle on a level surface, over a large sheet of paper or other clean surface.
  3. Wait 15 minutes.
  4. Inspect for drippings.

Are drippings present?

Go to Step 2

System OK

2

Can you identify the type of fluid and the approximate location of the leak?

Go to Step 10

Go to Step 3

3

  1. Visually inspect the suspected area. Use a small mirror to assist in looking at hard to see areas.
  2. Inspect for leaks at the following locations:
    • Sealing surfaces
    • Fittings
    • Cracked or damaged components

Can you identify the type of fluid and the approximate location of the leak?

Go to Step 10

Go to Step 4

4

  1. Completely clean the entire engine and surrounding components.
  2. Operate the vehicle for several kilometers, miles, at normal operating temperature and at varying speeds.
  3. Park the vehicle on a level surface, over a large sheet of paper or other clean surface.
  4. Wait 15 minutes.
  5. Identify the type of fluid, and the approximate location of the leak.

Can you identify the type of fluid and the approximate location of the leak?

Go to Step 10

Go to Step 5

5

  1. Visually inspect the suspected area. Use a small mirror to assist in looking at hard to see areas.
  2. Inspect for leaks at the following locations:
    • Sealing surfaces
    • Fittings
    • Cracked or damaged components

Can you identify the type of fluid and the approximate location of the leak?

Go to Step 10

Go to Step 6

6

  1. Completely clean the entire engine and surrounding components.
  2. Apply an aerosol-type powder, baby powder, foot powder, etc., to the suspected area.
  3. Operate the vehicle for several kilometers, miles, at normal operating temperature and at varying speeds.
  4. Identify the type of fluid, and the approximate location of the leak, from the discolorations in the powder surface.

Can you identify the type of fluid and the approximate location of the leak?

Go to Step 10

Go to Step 7

7

  1. Visually inspect the suspected area. Use a small mirror to assist in looking at hard to see areas.
  2. Inspect for leaks at the following locations:
    • Sealing surfaces
    • Fittings
    • Cracked or damaged components

Can you identify the type of fluid and the approximate location of the leak?

Go to Step 10

Go to Step 8

8

Use the J 28428-E High-Intensity Black Light Kit in order to identify the type of fluid, and the approximate location of the leak. Refer to the manufacturer's instructions when using the tool.

Can you identify the type of fluid and the approximate location of the leak?

Go to Step 10

Go to Step 9

9

  1. Visually inspect the suspected area. Use a small mirror to assist in looking at hard to see areas.
  2. Inspect for leaks at the following locations:
    • Sealing surfaces
    • Fittings
    • Cracked or damaged components

Can you identify the type of fluid and the approximate location of the leak?

Go to Step 10

System OK

10

  1. Inspect the engine for mechanical damage. Special attention should be shown to the following areas:
    • Higher than recommended fluid levels
    • Higher than recommended fluid pressures
    • Plugged or malfunctioning fluid filters or pressure bypass valves
    • Plugged or malfunctioning engine ventilation system
    • Improperly tightened or damaged fasteners in area of leak
    • Cracked or porous components
    • Improper sealant or gasket installation
    • Damaged or worn gaskets or seals
    • Damaged or worn sealing surfaces
  2. Inspect the engine for customer modifications.

Is there mechanical damage, or customer modifications to the engine?

Go to Step 11

System OK

11

Repair or replace all damaged or modified components.

Does the engine still leak oil?

Go to Step 1

System OK