How to Check Hydraulic Oil

Your manual clutch is operated by a complex system.

Some manual cars come with a hydraulic clutch. It's important to check the fluid in the hydraulic clutch at least every six months. Maintaining appropriate fluid levels increases the efficiency of the entire system. When you drive your car with an inadequate amount of hydraulic fluid over a long period of time, the clutch system in your car will operate poorly because of oxidation and rust, and it may be permanently damaged or ruined. To completely check the hydraulic fluid in your car, you will need to check the level, contaminants and chemical makeup of the fluid.

Things You'll Need

• Notebook
• Pen
• Turkey baster
• Small plastic container

Instructions

1. In the notebook, designate a place to track the last time you checked your hydraulic fluid, the results and the date of your next check.

2. Drive the car around the block several times so that the vehicle is at normal operating temperature.

3. Park the car, turn it off and put the parking brake on. Pop the hood.

4. Locate the master cylinder. This is located where the brake pedal meets the car wall. The fluid is contained in a small plastic cylinder.

5. Open the cap on the cylinder. Compare the fluid levels with the marks on the cylinder. There should be a mark for full, medium and low levels.

6. Draw a few drops of fluid from the filter with the turkey baster. Place the sample in a plastic container.

7. Examine the color of the fluid. Clean hydraulic fluid is a light amber color. If the fluid is dark or milky, it may have one or more contaminants in it and requires changing.

8. Smell the hydraulic fluid. If the smell is acidic, this may be another indication that the fluid is contaminated.

9. Take the sample to an automotive shop for analysis immediately if it appears and smells contaminated. Professional equipment can determine the viscosity; particle count; water percentage; iron, silicon and copper content; and oxidation of the oil. The entire system may need replacement if the oil is too contaminated.

10. Leave the hydraulic fluid in the cylinder if it appears and smells normal. Refill the fluid if it's below the full line marked on the cylinder. Pour the fluid directly into the cylinder, or drop it in with the turkey baster to avoid spilling.

11. Mark the date, time and results of your check in the notebook. Set the next check date for six months later.

Tips & Warnings

• Clean up spilled hydraulic fluid immediately. Hydraulic fluid can easily corrode the surfaces of your car.

References

• MTS: Hydraulic Fluid Care Guide