Perform a Cooling System Inspection and Test

Transcription

1 ,JOB SHEET 25 Perform a Cooling System Inspection and Test Name: Station: Date: l.d.3 NATEF Correlation This Job Sheet addresses the following NATEF task(s): 7.C.2 7.A.2 8.A.l5 Perform cooling system pressure tests; check coolant condition, inspect and test radiator, pressure cap, coolant recovery tank, and hoses; determine necessary action. (P-1) Perform cooling system pressure tests; check coolant condition, inspect and test radiator, cap (pressure/vacuum), coolant recovery tank, and hoses; perform necessary action. (P-1) Identify and interpret heating and air-conditioning concern; determine necessary action. (P-1) Perform cooling system pressure tests; check coolant condition, inspect and test radiator, pressure cap, coolant recovery tank, and hoses; determine necessary action. (P-1) Performance Objecfive(s) pon completion of this Job Sheet, you will be able to understand how to check the cooling system for roblems, perform tests related to the cooling system's performance and ability to seal, and determine what action(s) need to be taken to keep the cooling system operating properly. Tools and Materials Service manual Shop rag Vehicle Hoist Coolant pressure tester Coolant dye Technician's tool set Correct type coolant 4 or 5 gas analyzer Protective Clothing/Equipment Goggles or safety glasses with side shields Describe the vehicle being worked on: 92 Year Make Model VIN Engine type and size

2 Job Sheet PROCEDURE I. Research the history of the vehicle and check to see if there have been any specific issues concerning overheating, undercooling, or coolant loss. 2. Check for any related TSBs on overheating or undercooling. 3. After letting the engine cool down, carefully remove the radiator cap (or coolant recovery reservoir cap). lvarning: Serious injury can occur if the cap is removed while the vehicle is still hot! 4. Check the coolant condition by following the steps outlined in Job Sheet #24. Explain what problems you found with the coolant. 5. Check the level of coolant. If it is low, add the correct type of coolant. Note: Also check the coolant level and condition in the overflow/recovery reservoir. 6. Add the coolant dye to the system. Note: Smne technicians will leave the dye in the system and then drive the car to get the dye well circulated throughout the system. 7. Visually inspect the engine and cooling system for leaks. Make sure to check the following: D Hoses D Radiator D Engine core plugs D Connections D Clamps D Heater core D Water pump D Thermostat housing D Cylinder head gasket area D Intake manifold gasket area D Engine oil dipstick D Automatic transmission dipstick (if equipped) Note: You may need to raise the vehicle on the hoist to see all of the cooling system's components and hoses.

3 94 Job Sheet Did you find any leaks visually? 9. Using the coolant pressure tester, pressurize the cap to the manufacturer's recommended system pressure. What pressure did you use? Figure 21.4 A pressure tester is used to test the pressure cap. Figure 21.5 Cooling system pressure is printed or stamped on the cap. Imported cars often have a barometric pressure rating. Did the cap open properly at the right pressure?

4 Job Sheet Using the coolant pressure tester, pressurize the system to the manufacturer's recommended system pressure. Figure A pressure tester installed on a radiator filler neck. 12. The system should hold that pressure for at least 15 minutes. During that time visually inspect the components from the list in step 7. Explain if you found any leaks. 13. Does the system hold the pressure for 15 minutes? 14. If the cooling system did not hold the pressure for 15 minutes, and no external leaks were found, what areas/problems would you focus on? 15. Before disconnecting the pressure tester, apply 5 psi of pressure and start the engine. Did the reading go up almost immediately? 16. What could be the cause of such a problem?

5 96 Job Sheet 25 Remove the pressure tester, leave the radiator cap off, and start the engine. Use a 4 or 5 gas analyzer to detect if there is any presence of combustion gases coming from the radiator opening. Note: Make sure tlzat the exhaust gas analyzer tip (in let) does not touch the coolant. chamber Figure When there is an internal leak. coolant migrates into the cylinder when the engine is off and also during the intake stroke. During combustion. exhaust gas will leak into the cooling system. Figure A block check test samples air above the coolant. 18. What condition could cause combustion gases to be present in the cooling system? Problems Encountered ~

6 Job Sheet INSTRUCTOR EVALUATION 0 4 Mastered Task 0 3 Able to Perform Task Independently; Some Additional Training Suggested 0 2 Able to Perform Task with Close Supervision; Requires Additional Training 0 1 Unable to Perform Task 0 0 Not Attempted Comments Instructor Name: Date: Instructor Signature:

7 JOB SHEET 32 ~ Inspect! Adjust, or Replace Engine Drive Belts, Tensioners, Pulleys, and Hoses Name: Station: Date: NATEF Correlation This Job Sheet addresses the following NATEF task(s): l.d.4 l.d.5 6.D.3 7.C.3 Inspect, replace, and adjust drive belts, tensioners, and pulleys; check pulley and belt alignment. (P-1) Inspect and replace engine cooling and heater system hoses. (P-1) Inspect, adjust, or replace generator (alternator) drive belts, pulleys, and tensioners; check pulley and belt alignment. (P-1) Inspect engine cooling and heater system hoses and belts; perform necessary action. (P-1) Performance Objective(s) Upon completion of this Job Sheet, you will be able to understand how to inspect, replace, and adjust drive belts, tensioners, and pulleys. You will be able to check the pulley and belt alignment. Tools and Materials Shop rag Vehicle Service manual Technician's tool set Fluid catch pan/basin Correct type coolant Serpentine belt removal tool Cricket belt tensioner tester Pulley alignment laser (if available) Protective Clothing/Equipment Goggles or safety glasses with side shields Describe the vehicle being worked on: Year Make Model VIN Engine type and size , Cengage Learning, Inc. Licensed for one-time use by the purchaser onl y; no additional copying or retransmission is permitted.

8 122 Job Sheet 32 PROCEDURE 1. If the vehicle you are working on has a serpentine belt, remove the drive belt using the serpentine belt removal tool. If the vehicle you are working on has multiple drive belts, remove them according to the manufacturer's procedures. Warning: Do not bmd tlze belt smaller them the smallest pu ll ey~5 diameter. Do not twist the belt more than 90 degrees. Note: You will have to release the belt tension before removing the belt. There are several types of tensioning systems. See the pictures below. Square hole Off-center bolt Spring canister _ " g_ 0 u 0 -~ l Tensioner pulley Figure To install a V-ribbed belt with a spring-loaded belt tensioner, pull the pulley in the direction of the arrow to release belt tension. Figure To loosen tension on this belt. turn the off-center bolt in the direction of the arrow. alternator Whiteout Figure This belt is tensioned by an adjustable screw. Figure This belt is tensioned by the alternator. 2. Draw a picture of the drive belt routing in the space below. Note: Sometimes you can (ind the belt routing on a label under the hood or in the service manual. 2012, Cengage Learning, Inc. Licensed for one-time use by the purchaser only; no additional copying or retransmission is permitted.

9 Job Sheet With the belt(s) removed, count how many cracks there are in a 3-inch span. 4. Based on your visual inspection, should the belt be replaced? 5. With the belt removed, inspect the tensioner (if equipped). If it is an automatic tensioner place a wrench or ratchet on it and move it back and forth. It should not make any noises or have any looseness. The bearing should also not make any noises when the pulley is spun. Does it? 6. Remove the tensioner and inspect the surface of the mount. Clean the surface of the mount. 7. With the tensioner removed, inspect it for any damage. 8. If the tensioner is in good condition, reinstall it. Torque the fastener to specification. 9. Visually check the pulleys for any cracks, bends, damage, or worn bearings. 10. Mount the pulley alignment laser tool on the crankshaft pulley and check the alignment of the other pulleys. Note: If a pulley alignment laser tool is not available you can use a straightedge to check pulley alignment by placing the straightedge along both sides of one of the pulleys and lining it up to another pulley. 11. Are any of the pulleys bent? 12. Replace any bad pulleys and belt(s). Install the belt in the reverse order of removal. 13. If the system has a manual tensioner, check the service manual for the procedure to adjust the belt, and adjust it , Cengage Learning, Inc. Licensed for one-time use by the purchaser only; no additional copying or retransmission is permitted.

10 124 Job Sheet Measure and record the installed belt tension with the cricket belt tension tester. Note: Some manu(acturers require the belt deflection to be measured along the fi-ee span part o(the installed belt. N 0 N "' ] m f Figure Using a belt tension gauge to adjust a V-belt. Figure A c lic k-type belt tension gauge is used for measuring tension on V-ribbed and timing belts. 15. If the belt is not in the correct tension on a manual tensioning system, adjust it accordingly, 16. Explain what may need to be done if an automatic tensione<;l. belt system has less tension than the specification, 17. After installing the belt(s), start the engine and make sure that it does not squeak or jump. W a 1-ning: On se1pentine belt S)'Stems, make sure that the belt is secured and installed properly on each pulley. Failure to do so m ay shred the belt when the engine starts. 18. Visually check all of the hoses externally for any signs of cracking, wear, or bulging near their connections. Check the center of all of the hoses for softness. Explain any signs of wear. 19. Place a coolant catch basin under the radiator, open the petcock, and drain the radiator. 20. Remove all of the coolant hoses and inspect the inside of the hoses for wear, cracks, and buildup. Explain your findings. 2012, Cengage Learn ing, Inc. Li ce nsed for one-time use by the purchaser only; no additional copying or retransmission is permitted.

11 Job Sheet Figure 21.8 A special tool for loosening radiator hoses. Wet the tool first by dipping it in the radiator coolant. Figure The end of this radiator hose was damaged on the inside by electrochemical degradation. 21. Check the hose clamps to ensure that they are in good condition and are of the correct size. Task Completed 22. Using a steel brush, clean the hose fitting. Figure Clean the hose fitting before installing the new hose. 23. Reinstall the hose. Coat the inside part of the hose that touches the fittings with a nonhardening sealer. 24. Add the correct type and mixture of coolant to the system and bleed the air out. Note: See Job Sheet #27 for more information and directions on bleeding the air out of the system. 2012, Cengage Learn ing, Inc. Li ce nsed for one-time use by the purchaser only; no additional copying or retransmission is permitted.

12 126 Job Sheet 3 2 ~ Problems Encountered INSTRUCTOR EVALUATION D 4 Mastered Task D 3 Able to Perform Task Independently; Some Additional Training Suggested D 2 Able to Perform Task with Close Supervision; Requires Additional Training D 1 Unable to Perform Task D 0 Not Attempted Comments Instructor Name: Date: ~ fu~ructm~gn~ure: ~ 2012, Cengage Learn ing, Inc. Licensed for one-time use by the purchaser only; no additional copying or retran smission is permitted.

13 JOB SHEET 29 Inspect, Test, and Replace a Thermostat Name: Station: Date: NATEF Correlation This job Sheet addresses the following NATEF task(s): l.d.6 Inspect, test, and replace thermostat and gasket/seal. (P-1) 7.C.4 Inspect, test, and replace thermostat and gasket/seal. (P-1) 8.A.14 Verify engine operating temperature; determine necessary action. (P-1) 8.F.3 Remove and replace thermostat and gasket/seal. (P-1) l.d.13 Identify causes of engine overheating. (P-1) Performance Objective(s) Upon completion of this job Sheet, you will be able to understand how to inspect, test, and replace a thermostat. Tools and Materials Service manual Vehicle Scan tool Infrared temperature gun Hoist Technician's tool set Fluid catch pan/basin Correct type coolant RTV or new thermostat gasket Protective Clothing/Equipment Goggles or safety glasses with side shields Describe the vehicle being worked on: Year Make Model VIN Engine type and size , Cengage Learning, Inc. Licensed for one-time use by the purchaser only; no additional copying or retransmission is permitted.

14 110 Job Sheet 29 PROCEDURE 1. Research the history and TSBs of the vehicle and check to see if there have been any specific issues concerning overheating, undercooling, or coolant loss. Task Completed 2. Find the correct operating temperature using the service manual. Let the engine warm up and check the temperature of the engine using the dash gauge, a scan tool, or their gun. 3. Check the operation of the thermostat by watching the scan tool data or using the IR gun on the upper radiator hose. Is the thermostat opening and closing properly? 4. Let the engine cool down. Then carefully remove the radiator cap (or coolant recovery reservoir cap). Wa rning: Serious injur)l can occur i(t:he cap is removed while the vehicle is still hot! 5. Open the radiator petcock and drain the coolant from the radiator into the catch basin until the level of coolant is below the thermostat. Note: Make sure to use the sa(e and appropriate m ethods o( disposing and reqcling o( coolant. 6. Remove the correct radiator hose. 7. Remove the thermostat housing and clean the gasket mating surface. 8. Remove the thermostat and inspect it. Is there anything wrong with the thermostat visually? 9. Clean the mating surfaces of the thermostat housing. 10. Optional: You can test the operation of the thermostat by placing it in a canister filled with an antifreeze and water mixture. Hand the thermostat in the canister with a piece of wire. Heat the canister and watch the temperature. Check to see if the thermostat opens when it should. Explain what happened. 2012, Cengage Learning, Inc. Licensed for one-time use by the purchaser only; no additional copying or retransmission is permitted.

15 Job Sheet Check temperature when thermostat Figure Checking thermostat operation. 11. Reinstall the new thermostat in the same position it came out of. Note: Compare the old thermostat to the new one. Make sure they are the same. Task Completed 12. What is the torque specification for the thermostat housing? 13. Install the thermostat housing with a new gasket or a manufacturer-approved RTV. Torque it to specification. 2012, Cengage Learning, Inc. Licensed for one-time use by the purchaser only; no additional copying or retransmission is permitted.

16 112 Job Sheet 29 Recess Figure This thermostat fits into a recessed area. 14. Reinstall the upper radiator hose. 15. Add the correct type and mixture of coolant to the system and bleed the air out. Note: See fob Sheet #27 for more information and directions on bleeding the air out of the system. 16. Based on your testing, was the thermostat a cause of overheating?

17 Job Sheet Problems Encountered INSTRUCTOR EVALUATION 0 4 Mastered Task 0 3 Able to Perform Task Independently; Some Additional Training Suggested 0 2 Able to Perform Task with Close Supervision; Requires Additional Training 0 1 Unable to Perform Task 0 0 Not Attempted Comments Instructor Name: Date: Instructor Signature:

18 JOB SHEET Flush and Refill a Cooling System Name: Station: Date: NATEF Correlation This Job Sheet addresses the following NATEF task(s): l.d.7 7.C.6 Test coolant; drain and recover coolant; flush and refill cooling system with recommended coolant; bleed air as required. (P-1) Flush system, refill system with recommended coolant; bleed system. (P-2) Performance Objective(s) Upon completion of this Job Sheet, you will be able to understand how to properly drain the coolant, flush and refill the cooling system, and bleed the air out of the system. Tools and Materials Service manual Shoprag Vehicle Hoist Coolant pressure tester Technician's tool set Correct type coolant Fluid catch pan/basin Coolant recycling machine Air bleed device (if available) Protective Clothing/Equipment Goggles or safety glasses with side shields Describe the vehicle being worked on: Year Make Model VIN Engine type and size PROCEDURE 1. Let the engine cool down. Then carefully remove the radiator cap (or coolant recovery reservoir cap). 102 Warning: Serious injury can occur if the cap is removed while the vehicle is still hot!

19 Job Sheet Check the coolant condition by following the steps outlined in Job Sheet #24. Explain what problems you found with the coolant. 3. Determine whether you should drain the coolant and refill the system with new coolant or if you should flush the cooling system. Note: Steps 4-8 are for draining and refilling the system. 4. Hoist the vehicle in the air and prepare the coolant catch basin. 5. Drain the coolant into the catch basin by opening the radiator petcock and the engine block drain plug. 6. Reinstall the engine block drain plug with the appropriate sealant and close the radiator petcock. 7. Lower the vehicle and describe the correct type and mixture of coolant you need to add. 8. After filling the system you will need to bleed the air out. See steps for directions on bleeding the air out. Note: Steps 9-13 are for flushing the system. 9. Prepare the coolant flush machine by installing the hoses in their appropriate places. Figure A coola nt exchanger.

20 104 Job Sheet Fill the flush machine with the correct type and mixture of coolant and describe the type and mixture of coolant you added. 11. Turn the coolant flush machine on and flush the old coolant out of the system. Watch as the container fill s. 12. Using the flush m achine, fill the system to the correct level. 13. If the coolant flush machine can bleed the air out of the system, do so. For those machines that cannot, follow steps N ote: Steps are for bleeding the air out of the system. 14. You will need to bleed the air out of the system. Some vehicles have air bleed screws in the cooling system. If the vehicle you are working on has bleed screws, bleed the air out by running the engine with the heater on high and continually opening the bleed screws to check for air. Figure This water pump has cavitation damage. which happens when air bubbles form and then explode in the coolant. 15. If the radiator cap opening is significantly higher than the rest of the cooling system the air can be bled out through that opening by gravity. Either jack the front wheels off the ground and support it with jack stands or drive only the front wheels of the car onto a drive-on rack. Continue to run the engine until you do not see any air bubbles coming out of the radiator. 2012, Cengage Learning, Inc. Licensed for one-time use by the purchaser only; no additional copying or retransmission is permitted.

21 Job Sheet Another way of removing air from the system uses a coolant pressure tester. Using the coolant pressure tester with the engine off, pressurize the system to the manufacturer's recommended system pressure. Then loosen the upper radiator hose clamp until coolant starts coming out. Note: You may need to repressurize the tester a second or third time. This depends on how much a ir is in the system. 17. If you have an air bleed device, install it in the radiator opening and siphon the air out of the system. This process works on the venturi principle of air pressure and movement. Problems Encountered INSTRUCTOR EVALUATION 0 4 Mastered Task 0 3 Able to Perform Task Independently; Some Additional Training Suggested 0 2 Able to Perform Task with Close Supervision; Requires Additional Training 0 1 Unable to Perform Task 0 0 Not Attempted Comments Instructor Name: Date: InstructorSignature:

22 JOB SHEET 9 < Perform an, " h, ~ I and Filter Change Name: Station: Date: NATEF Correlation This Job Sheet addresses the following NATEF task(s): l.d.13 8.F.6 Perform oil and filter change. (P-1) Perform engine oil and filter change. (P-1) Performance Objective(s) Upon completion of this Job Sheet, you will be able to perform an engine oil and filter change. Tools and Materials Shop rag Correct amount and type engine oil Service manual Wrenches Oil filter wrench or removal tool Protective Clothing/ Equipment Goggles or safety glasses with side shields Describe the vehicle being worked on: Year Make Model VIN Engine type and size PROCEDURE 1. What are the API service rating, SAE viscosity, and quantity of oil you will need for this vehicle? Refer to the service manual or the owner's manual for the correct specifications. API Rating ILSAC Rati.PS:f t SAE Viscosity ACEA Rating.m Quantity 38

23 Job Sheet Check the container of oil that you are planning on using for this oil change. Do the ratings meet the requirement for the vehicle you are working on? Figure The viscosity and API rating of the oil are printed on the oil container using this standard industry symbol. 3. Make sure that the engine is at or near operating temperature. For the best results you should drain the crankcase when the engine is near operating temperature. The oil will flow faster and more deposits will be suspended in the oil that is to be drained, instead of collecting at the bottom on the pan. Warning: Before starting the engine check the oil level and ensure that it is safe to start. Task Completed _ 4. Roll the window down and then open and stabilize the hood. Then place fender covers on the front body parts. 5. Check the oil level and condition before draining it. Describe what condition it is in and how that may relate to a possible engine problem. 6. Remove the oil fill cap. u t Figure 12.6 The dipstick ind icates the oil level in the crankcase. N 0 N <> ~. 3 " 2012, Cengage Learning, Inc. Licensed for one-tim e use by the purchaser only; no additional copying or retransmission is permitted.

24 40 Job Sheet 9 Raise the vehicle using a hoist or floor jack. Warning: Be sure to operate the hoist proper!)' and sa{el)'. I{ )'OU are using a floor jack, place the vehicle so that it is level on jack stands. 8. Place the oil drain collection pan under the oil drain plug. 9. What condition is the oil drain plug in? Is the bolt head rounded? Are there any notches or markings on it? 10. Find the correct size wrench to fit the oil drain plug. What size is it? 11. Remove the oil drain plug carefully while adjusting the position of the oil catch pan. As more oil is drained from the pan the oil stream running out of the pan will change to a slow drip. The oil catch pan position may need to be changed. Do not leave the oil catch pan unattended until the oil stream.12. has slowed to a slow drip. Task Completed Check the condition of the oil drain plug. What condition are the threads in? If there is a gasket on it, what condition is it in? Note: I{ the gasket is not usable, replace it. Figure Check the condition of the gasket on the drain p lug. 2012, Cengage Learning, Inc. Licensed for one-time use by the purchaser only; no additional copying or retransmission is permitted.

25 Job Sheet Allow the oil to drain until it no longer drips and thread in the oil drain plug and tighten it to the manufacturer's specifications. 14. Locate the oil filter. Describe h ow you are planning on removing it (Do you have to remove it from the bottom or top, are there any special covers to remove first, or is there a special socket or tool that needs to be used?). 15. Position the oil catch pan and then using either your hand or the oil filter wrench remove the oil filter. Note: Make sure that the oil filter wrench or adapter does not come in contact with any electrical connections such as the starter or alternator. Task Completed Figure This type of oil filter wrench should be placed as close to the filter base as possible. 16. Check to make sure that the oil filter gasket was removed with the old oil filter. What do you think could happen if it is not removed? 17. Clean the oil filter housing gasket surface with a clean shop rag to ensure a good gasket mating surface. 18. Compare the old oil filter and gasket to the new one. What do you think could happen if the incorrect oil filter or gasket were accidentally installed?

26 Job Sheet 9 Place a small amount of oil on and around the new oil filter gasket and then install it by hand until it contacts the mating surface. Task Completed Figure Lubricate the filter 0-ring before installing the filter. 20. If there is a manufacturer's specification to tighten the oil filter to, then use it. Otherwise refer to the oil filter installation instructions on the box it came in or use the accepted industry standard of tightening it Vz to 1 full turn past the contact point. This will allow for the gasket to remain sealed until the next oil change. 21. Add the correct type and quantity of oil (refer to step 1). 22. When you are done filling the oil replace the oil filler cap and check the dipstick to ensure that it is above the minimum level. 23. Start the engine and watch the oil pressure gauge to make sure it goes up within a few seconds (or watch the oil pressure warning light and make sure it goes off within a few seconds). Watch under the vehicle to make sure that there is no large oil leak. Warning: If the oil pressure does not go up within a few seconds or if you see a large leak under the car turn the engine off immediately and see your instructor. 24. Turn the engine off and recheck the oil level on the dipstick. Draw a picture of the oil dipstick, the marking on it, and the current oil level. 2012, Cengage Learning, Inc. Licensed for one-time use by the purchaser only; no additional copying or retransmission is permitted.

27 Job Sheet Check for oil leaks on the floor, especially around the oil drain plug. If any leaks were noticed, explain where you think they were coming from. 26. After completing the oil change, dispose of the oil and oil filter properly. What is the shop's method for disposing of used oil and oil filters? Problems Encountered INSTRUCTOR EVALUATIO N 0 4 Mastered Task 0 3 Able to Perform Task Independently; Some Additional Training Suggested 0 2 Able to Perform Task with Close Supervision; Requires Additional Training 0 1 Unable to Perform Task 0 0 Not Attempted Comments Instructor Name: Date: Instructor Signature: