Remove, Bench Bleed, and Reinstall Master Cylinder

Lesson Plan for

AUT 186-187/AUT 292

Automotive Service Technology Section C/Automotive Special Problems

Course HS Title: / Automobile Service Technology/Special Problems / Program:
KCTCS Courses included in HS Title: (Lesson is prepared for course highlighted.)
KCTCS Course No. / KCTCS Course Title
AUT 110 / Brake Systems
Introduction/Context / This lesson will instruct the student on how to Remove, Bench Bleed, and Reinstall Master Cylinder. Knowledge of these techniques and the skills required to correct problems associated with this task are necessary for a student to acquire if they wish to compete for high paying, high skilled jobs in an Automotive Repair Facility. Entry level technicians need to be able to perform this task to 100% accuracy. Incorrectly performing this task can lead to an automobile accident or create customer satisfaction issues.
Prepared By / School / Date:
Grade Level / No. Students / No.IEP's: / Lesson Length:
Task
Remove, bench bleed, and reinstall master cylinder.
No. / Objective
1 / Given the proper tools and instruction, the student will be able to Remove, Bench Bleed, and Reinstall Master Cylinder, and pass a written test covering the task with 100% accuracy.

Connections

Skills Standards:
OH 001
OH 002
OH 003
OD 002
OD 003
OD 005
Common Core Technical Standards:
TD-SYS-2
New Common Core Standards:
RST 11-12.2
RST 11-12 3
New Generation Science Standards:
HS-PS2-1.
HS-PS3-3.

INSTRUCTIONAL MATERIALS/TECHNOLOGY

Teacher Designed Materials and Other Handouts

Instruction sheet on master cylinder removal adhering to manufacturer's specifications. Tools include a brake bleeder Kit, flare-nut wrenches, a vise, cloths, a catch basin and the proper brake fluid.


Textbooks and Workbooks

Author / Title/ISBN No. / Edition / Publisher / Pages
Duffy / Modern Automotive Technology / Goodheart, Wilcox
Automotive Excellence,Vol. 1 / Glencoe
Automotive Brake Systems (Today's Technician) 2nd Edition / Delmar


Supplies

Quantity / Item / Source
As Needed / Bench Bleeder Kits / Various
As Needed / Brake Fluid / Various


Equipment

Quantity / Item / Source
As Needed / Brake Fluid / Various
As Needed / Flare-Nut wrenches / Various
As Needed / Bench Bleeder Kits / Various
As Needed / Vice / Various


Content/Presentation/Demonstration Outline

Demonstrate the proper way of removing master cylinder. Instruct students to remove the negative battery cable for safety. Be sure to use a towel to remove any dirt that might enter the open brake lines or the vacuum booster. If the master cylinder has an electrical connector to the fluid level sensor, unplug it. Place some sort of a container or catch basin under the master cylinder to catch brake fluid that will leak when the lines are disconnected. Use the proper sized flare-nut wrench to disconnect the brake lines from the master cylinder. Once you get the brake lines disconnected, plug the end of each line to keep dirt and debris out of the lines and help prevent excessive brake fluid loss. Remove the nuts that attach the master cylinder to the vacuum booster. Lift the master cylinder out of the vehicle. Clean the vacuum booster and master cylinder contact areas with a clean towel. Be sure to tell students that brake fluid can damage a vehicles paint job!
Bench Bleeding the Master Cylinder: Instruct students that bench bleeding is a method used to force all the air out of a unit. Mount the master cylinder in a vice. Tell students not to apply excess pressure. It can easily crack or shatter. Make sure to mount the master cylinder so that the bore is in a horizontal position. Connect fittings into master cylinder outlet ports and connect the tubing to the fittings. Master cylinder brake bleeding kits come with the tubing and fittings you will need. Bend the tubing lines so the ends are in the chambers of the master cylinder reservoir. Fill the chambers with fresh brake fluid, and make sure the level is above the ends of the tubes.
Using a wooden dowel or the blunt end of a punch, slowly push on the master cylinder pistons until they are bottomed out. Watch for bubbles to appear at the tube ends immersed in fluid. Release the cylinder pistons and let them return to their original position. Pump the cylinder piston until there are no bubbles appearing in the fluid. Remove the tubes from the outlet ports and plug the openings with some sort of temporary plug. You can use your fingers. Keep the ports covered until you install the cylinder. Install the master cylinder on the vehicle.
Installation is the reverse of removal. Attach the lines, but do not tighten. Depress the brake pedal several times to force out any air that might be trapped in the connections. Be sure to soak up the brake fluid with a rag to prevent any damage to the paint. When the air is gone, tighten up the connections, and fill the master cylinder with fresh brake fluid. Be sure students know they must bleed the whole system once this is done!


Applications/Practice

1 / Students can practice this task by using shop car and following the manufacturer's instructions on the proper removal of the unit off the vehicle. Students can put the master cylinder in a vise and practice techniques used for bench bleeding. When done, students can reinstall the master cylinder as per instructions, make sure all the air has been purged from the cylinder, and tighten the connections.


Evaluation and feedback Prior to Testing or Lab Work

1 / Objective 1. / Formative assessment / Instructor will observe students as they practice the procedure to assure correct procedure and safety practices are being followed. A checklist will be utilized to chart student progress on the task. Questioning techniques will be utilized as necessary to demonstrate student comprehension / Adaptations and/or accommodations for special needs students will be added if required.


STUDENT ASSESSMENT:(Assess student progress with performance criteria.)

1 / Objective 1 / Summative assessment / written test questions on stated objective / adaptation and / or accommodations for special needs students will be added if required
IMPACT--Reflection/Analysis of Teaching and Learning: (How did students’ progress in relation to the state objectives? Was the instruction successful? Analyze samples of student work particularly that which is unsatisfactory, for the purpose of planning further instruction.)
REFINEMENT--Lesson Extension and Follow-up: (To be filled in as the lesson is modified during initial planning and/or during the teaching learning process.)