3408 TRUCK ENGINE Caterpillar

The BrakeSaver provides auxiliary braking to slow the truck and to control speed on long grades. Governing the deceleration or downgrade speed of a vehicle by using the BrakeSaver results in greater safety, and reduces wear on brake linings and brake drums. It helps save the service brakes for emergency stopping requirements.

Braking effort is a direct function of engine speed. The greater the engine speed the greater the braking effort.

The BrakeSaver utilizes the engine oil and cooling systems and eliminates the need for additional oil or cooling systems.

When changing the engine crankcase lubricating oil, it is also necessary to drain the oil from the oil cooler. Remove the drain plug located on the bottom of the BrakeSaver control valve.

Make a frequent check of coolant and oil lines for leakage and deterioration of hoses. If an oil or water leak develops, do not operate the engine until proper repairs can be made.

Scheduled maintenance on the BrakeSaver, or additional engine maintenance, is not required.

Trucks equipped with the BrakeSaver require an additional amount of engine lubricating oil. See the LUBRICATION AND MAINTENANCE CHART for service intervals.

At oil change intervals, fill the crankcase to the proper level. Operate the engine for a short period. Stop the engine and check the engine oil level. Be sure it is at the full mark on the dipstick. Add oil if necessary.

MANUAL CONTROL: The hand operated control lever, usually mounted on the steering column, provides a smooth modulated application of the BrakeSaver to apply any desirable retarding of the vehicle, up to engine rating. This controlled modulation of the BrakeSaver is especially desirable on slippery roads. Increasing or decreasing the BrakeSaver action is accomplished by moving the control lever.

AUTOMATIC CONTROL: The mode selector switch must be in the AUTOMATIC MANUAL position for automatic control. The BrakeSaver will then automatically shut off when the clutch is disengaged. It will engage again when the clutch is re-engaged.

Slight accelerator pressure will turn off the BrakeSaver. This will allow the truck to coast and be retarded only by engine friction and normal rolling resistance.

GAUGES: The BrakeSaver CONTROL AIR PRESSURE gauge indicates the pressure at the BrakeSaver control valve. Air pressure should not exceed 50 psi (345 kPa).

If the indicator shows reduced or no pressure, stop the vehicle or operate at a reduced speed. Control vehicle stopping with proper downshifting and service brakes until proper repairs are made.

The BrakeSaver oil temperature gauge indicator should register in the NORMAL (green) range. If the indicator moves to the red range, move the BrakeSaver manual control lever to the OFF position.

Operate the vehicle with the service brakes only, or stop the vehicle and let the engine idle until the oil temperature registers in the NORMAL range.

No special skills are required to operate a vehicle with a BrakeSaver. However, it requires the driver to watch the engine speed and the BrakeSaver oil temperature.

For maximum BrakeSaver effectiveness, select the proper gearing to keep the engine RPM as close to the rated speed as possible.

Manual operation adds modulation to the BrakeSaver control and allows the driver to match driving conditions to any load or hill. Do not control the vehicle speed with the accelerator while the manual control is on.

The BrakeSaver is not an emergency or quick stop brake.

Allow a 2 second delay for full engagement and full disengagement.

Use the service brakes for quick stops.

To prevent unnecessary fuel consumption and possible heat build-up, do not leave the BrakeSaver in operation when the engine is idling while parked. Place the control selector switch in MANUAL position, and the manual control lever in the OFF position.

DRIVER OPERATIONAL CHECKS: There are two quick operational checks the driver can make to determine if the BrakeSaver is operating properly. Also, if the control valve spool is operating freely in the control.

1. To check retarding horsepower:

a. Place the transmission in neutral.

b. Run the engine at high idle RPM.

c. Engage the BrakeSaver fully.

d. The engine speed should drop approximately 150 ± 50 RPM.

2. To check control valve spool free movement:

a. Start the engine and run it until the air system is at maximum pressure.

b. Shut off the engine and engage the BrakeSaver before the air pressure drops below 70 psi (480 kPa).

c. Disengage the BrakeSaver and listen for a "klunk" sound. This "klunk" sound is the control valve hitting the control valve end cover. This indicates that the control valve is free and the control springs are operating normally. Also, that the air is venting properly from the control valve.

Daily Care And Report

A daily inspection of the engine should be made to prevent premature engine failure. If corrective steps are taken immediately on discovery of a malfunction, fewer forced stops will be required. This will help obtain the most economical operation. If any abnormal readings or observations are found, be sure to report it. Points to be checked daily are:

1. Oil, air, water or fuel leaks.

2. Cooling system: Clean the radiator core and add coolant or antifreeze as necessary. Be sure the radiator cap seal is in good condition and the cap is installed tightly.

3. Unusual engine noise.

4. Excessive use of crankcase lubricating oil, coolant, battery fluid or fuel.

5. Fuel pressure gauge: Check with the engine running. Change the fuel filter if indicator is in the red range.

6. Air cleaner indicator, if equipped: Inspect with the engine running. Service the air cleaner when the red piston remains in the UP position.

7. Unusual turbocharger noise or vibration: A muffled high pitch whine is the normal sound.

8. Cleanliness: Dirt should not be allowed to accumulate on the engine.