cooling systems auto 1 if you did your homework, this will make more sense! if you didn’t, get it...

COOLING SYSTEMSAUTO 1

If you did your homework, this will make more sense!

If you didn’t, get it turned late tomorrow.

We will take notes in a little bit.

WHAT MAKES AN ENGINE RUN?

NO! WHAT REALLY MAKES AN ENGINE RUN?

HEAT

•WHERE DOES THE HEAT COME FROM?

•HEAT CAUSES EXPANSION WHICH CAUSES?

•PRESSURE PUSHES PISTON DOWN WHICH MAKES THE WHEELS GO ROUND AND ROUND

•PRESSURE!

ENERGY……….

THAT’S RIGHT, BURNING FUEL

TYPES OF ENERGY

• ELECTRICAL

• CHEMICAL

• NUCLEAR

• THERMAL

• RADIANT

• MECHANICAL

• FUEL IS CHEMICAL ENERGY– WHEN BURNED COVERTS TO...

• THERMAL ENERGY (HEAT)– WHICH CAUSES EXPANSION

(PRESSURE)– WHICH COVERTS TO…

• MECHANICAL ENERGY– WHICH WE USE TO MOVE THINGS

• THIS IS ENERGY CONVERSION

ENERGY CONVERSION?• REMEMBER, YOU CAN’T CREATE OR

DESTROY ENERGY• YOU CAN ONLY CHANGE ITS FORM

– THIS IS ENERGY CONVERSION

• IN OTHER WORDS, THERE IS ONLY SO MUCH ENERGY HERE ON EARTH AND WE CAN’T ADD TO IT OR RUN OUT OF IT. NEVER USE IT UP!

• WOW

WE HAD BETTER WRITE THIS DOWN IN OUR FUEL NOTES.

• FUEL IS CHEMICAL ENERGY– WHEN BURNED COVERTS TO...

• THERMAL ENERGY (HEAT)– WHICH CAUSES EXPANSION

(PRESSURE)– WHICH COVERTS TO…

• MECHANICAL ENERGY– WHICH WE USE TO MOVE THINGS

• YOU CAN’T CREATE OR DESTROY ENERGY, YOU CAN ONLY CHANGE ITS FORM!

• ITS FORM IS CHANGED BY A CHEMICAL REACTION.

• THE MOST COMMON TYPE OF CHEMICAL REACTION IS COMBUSTION

• LETS MOVE ON

LETS CONCENTRATE ONWE HAD BETTER WRITE THESE DOWN IF WE DON’T ALREADY KNOW THEM

• HEAT IS THE RAPID MOVEMENT OF ATOMS OR MOLECULES IN A SUBSTANCE ABSOLUTE 0 IS-460F (-273C)

• HEAT IS A FORM OF ENERGY

• HEAT IS MEASURED BY……….– TEMPERATURE

• DEGREES IN FAHRENHEIT OR CELSIUS

– BTU’s• VOLUME OF HEAT

HEAT

BTU,s ????

• BRITISH THERMAL UNIT– ONE (1) BTU WILL RAISE THE

TEMPERATURE OF ONE (1) POUND OF WATER ONE (1) DEGREE FAHRENHEIT (F)

WHAT IS THE DIFFERENCE BETWEEN TEMPERATURE AND

BTU,s ?• TEMPERATURE IS THE DEGREE OF

HEAT OR HOW HOT.– FOR EXAMPLE, A MATCH MIGHT BURN AT

400 DEGREES F.

• BTU IS THE VOLUME OF HEAT OR HOW MUCH, BUT NOT TEMPERATURE.– EXAMPLE, THE AMOUNT HEAT IT TAKES

TO HEAT THIS ROOM, OR RAISE THE TEMPERATURE OF THIS ROOM

• COMBUSTION TEMPERATURES CAN REACH UP TO __________ DURNING THE COMBUSTION PROCESS. PAGE 92 OF YOUR HOMEWORK.

• THINK ABOUT THIS QUESTION BEFORE YOU FORM AN ANSWER. WOULD YOU WANT THE VOLUME OF HEAT FROM ONE 6000 DEGREE F POWER STROKE TO HEAT THIS ROOM?

• NOT IN THE WINTER TIME

DO WE HAVE THE IDEA OF THE DIFFERENCES

BETWEEN TEMPERATURE OF HEAT AND VOLUME OF

HEAT?

GALLON OF GASOLINE• ONE GALLON OF GASOLINE HAS

APPROXIMATELY 115,000 BTU,s.• THAT MEANS THE AVERAGE GALLON OF

GASOLINE HAS THE ENERGY TO RAISE THE TEMPERATURE OF ONE POUND OF WATER 115,000 DEGREES F. (IMPOSSIBLE) OR…

• RAISE 115,000 LBS OF WATER ONE DEGREE F. OR

• RASIE 1,150 LBS OF WATER (ABOUT 150 GALS.) 100 DEGREES F.

• OTHER FUELS HAVE DIFFERENT BTU,s

• DIESEL HAS APPROXIMAELY 135,000 BTU,s PER GALLON

• ALCOHOL HAS APPROXIMATELY 85,000 BTU,s PER GALLON

HOW DOES THE ENGINE USE THIS ENERGY?

ONE GALLON115,000 BTU

COST $1.30 - $1.60

35% LOST OUT EXHAUST

LOST TO EXHAUST

35% LOST TO COOLING SYSTEM

LOST TO EXHAUST

LOST TO COOLING

15% LOST TO FRICTIONAL LOSSES

LOST TO EXHAUST

LOST TO COOLING

FRICTIONAL LOSSES

APPROXIMATELY 15% LEFT TO MOVE THE CAR.

LOST TO EXHAUST

LOST TO COOLING

FRICTIONAL LOSES

WOW

WHAT A WASTE!!!!!

IF TODAYS VEHICLES CAN AVERAGE 20 MILES PER GALLON NOW USING JUST 15% OF THE ENERGY IN A GALLON OF FUEL...

WHAT KIND OF MILAGE COULD THEY GET IF WE COULD IMPROVE

IT TO 50% OF THE ENERGY IN A GALLON OF FUEL???

• TODAY – 20 MPG USING 15%

OF ENERGY

• TOMMOROW??– 70 MPG USING 50%

OF ENERGY

MILES PER GALLON AVERAGES

SO WHY DO WE HAVE TO REMOVE 35% OF THE HEAT WITH A COOLING SYSTEM?

•LIMITED BY CURRENT MATERIAL TECHNOLOGY

•LIMITED BY CURRENT LUBRICATION TECHNOLOGY

WE JUST PAID BIG MONEY TO BUY FUEL TO CREATE HEAT!

CYLINDER WALL TEMPERATURE MUST BE

KEPT BELOW 500 DEGREES F.WHY?

OIL BREAKS DOWN (BURNS)

CAN YOU SAY DRY FRICTION?

HEAT TRANSFERMAKE SURE YOU GET THIS IN YOUR NOTES

THE MOVEMENT OF HEAT FROM ONE PLACE TO

ANOTHER

THREE TYPES OF HEAT TRANSFER

•CONDUCTION

•CONVECTION

•RADIATION

CONDUCTION

TRANSFER OF HEAT THRU SOLIDS

CONVECTION

TRANSFER OF HEAT THRU LIQUIDS OR VAPORS

RADIATION

TRANSFER OF HEAT THRU LIGHT RAYS

EXPERIMENTTIME

DAY TWO

LETS REVIEW

• CAN’T DESTROY OR CREATE ENERGY– ENERGY CONVERSION

• SIX TYPES OF ENERGY– IN AUTOMOBILES WE USE, ELECTRICAL,

THERMAL, CHEMICAL, RADIANT, AND MECHANICAL. DON’T USE NUCLEAR

• HEAT– WHAT IT IS AND HOW IT IS MEASURED– DIFFERENCES BETWEEN TEMP AND BTU

• DIFFERENT FUELS HAVE DIFFERENT ENERGY CONTENT (BTU)

• TODAYS ENGINES ARE NOT VERY EFFICIENT

APPROXIMATELY 15% OF THE ENERGY IN GASOLINE

IS USED TO MOVE THE CAR.

LOST TO EXHAUST

LOST TO COOLING

FRICTIONAL LOSES

WHICH TYPE OF HEAT TRANSFER DO WE USE IN

AN ENGINE?

• DURING COMBUSTION– EXPLOSION WOULD HAVE TRANSFER

THRU RADIATION TO HEAD, CYLINDER WALL, AND TOP OF PISTON

– ALSO TRANSFER THRU CONVECTION TO HEAD, CYLINDER WALL AND TOP OF PISTON and….

• FROM INSIDE OF CYLINDER WALL AND HEAD…– HEAT TRANSFER THRU CONDUCTION TO

OUTSIDE OF CYLINDER WALL AND HEAD

• FROM OUTSIDE OF CYLINDER WALL AND HEAD…– HEAT TRANSFER THRU CONVECTION

• TO SURROUNDING AIR ON AIR COOLED• TO SURROUNDING LIQUID IN WATER JACKET

ON LIQUID COOLED

SO WE USE ALL TYPES OF HEAT TRANSFER TO COOL

AN ENGINE

TYPES OF COOLING SYSTEMS

AIR COOLED

LIQUID COOLED

LETS TAKE THE SIMPLE SYSTEM FIRST

TYPES OF AIR COOLING

FORCED DRAFT

OPEN DRAFT

WE WILL NEED THIS IN OUR NOTES

FORCED DRAFT

USUALLY USED ON ENGINESTHAT ARE STATIONARY OR

THAT AREN’T MOVEDVERY FAST

HAS A FAN TO FORCE AIRACROSS ENGINE

USES SHROUDS TO DIRECTAIR TO PROPER PLACES

ALL YOUR ENGINES AREFORCED DRAFT

YOUR FLYWHEEL ACTS ASTHE FAN

LETS ADD THAT TO OUR ENGINE PARTS LIST PURPOSES FOR THE

FLYWHEEL

A. TO KEEP ENGINE MOVING THRU NON POWER STROKES

B. ACTS AS A FAN FOR THE COOLING SYSTEM

C. WE WILL GET

D. C. AND D. LATER

SHROUDS FOR FORCED DRAFT

WHAT WOULD HAPPEN IF WE LEFT ONE OFF?

NOTICE THE FINS.

WHAT WOULD HAPPEN IF WE BROKE ONE OFF?

THESE ARE CALLED HEAT DISAPATING FINS.

THEY ADDSURFACE AREA

SO MOREHEAT CAN

BE REMOVED.

LETS LOOK AT AN OPEN DRAFT AIR COOLED ENGINE

HAS NO FAN

ENGINE MUST MOVETHROUGH AIR FOR

AIR MOVEMENT

MAY OR MAY NOT HAVESHROUDS

TYPCIAL AIR COOLEDMOTORCYCLE ENGINE

REMEMBER ENGINEMUST MOVE THROUGH

AIR TO GET PROPERCOOLING ON THE

OPEN DRAFT DESIGN!

WITHOUT AIR MOVEMENT,ENGINE CAN OVERHEAT.

ESPECIALLY ON HOT DAYS.

MUST HAVE HEATDISAPATING FINS AS WELL

CHECK OUT THE HEAT DISAPATING FINS ON THIS

CUT AWAY ENGINE.

LETS MAKE SURE WE HAVE THIS IN OUR NOTES

• OPEN DRAFT– NO FAN, ENGINE HAS TO MOVE THRU

AIR FOR COOLING

• FORCED DRAFT– HAS FAN TO FORCE AIR FLOW FOR

COOLING

SO WHAT DO WE NEED TO DO TO TAKE CARE OF AIR COOLING SYSTEMS ?

AIR COOLING MAINTENANCE

LETS MAKE SURE WEGET THIS IN OUR NOTES.

• KEEP FINS CLEAN OF GREASE AND DEBRIS– CLEAN WITH SOLVENT OR HOT SOAPY

WATER OR CAN CLEAN WITH DEGREASERS– DON’T CLEAN WHILE ENGINE IS HOT– MAY HAVE TO REMOVE SOME SHROUDS TO

GET TO ALL FINS

• KEEP ALL SHROUDS IN PLACE DURING USE

That’s All folks!That’s All folks!

FOR AIR COOLING MAINTENANCE

IT IS THAT SIMPLE

NEXT, WE ARE READY FOR LIQUID COOLING?

LIQUID COOLING

HERE WE COME!

LIQUID COOLING IS MUCH MORE EXPENSIVE THAN

AIR COOLING.

PURPOSE OF COOLING SYSTYEM

BETTER GET THIS IN OUR NOTES

• KEEP ENGINE AT MOST EFFICIENT OPPERATING TEMPERATURE– TOO COLD = WASTED ENERGY (BTU)– TOO HOT = LOSS OF LUBRICATION

• AIR COOLED IS NOT ACCURATE– DESIGNED TO OVERCOOL

• LIQUID COOLING IS DESIGNED TO GET THE ENGINE TO WARM UP QUICKLY YET NOT OVERHEAT

HERE ARE THE COMPONENTS OF THE LIQUIDCOOLING SYSTEM.

WHAT IS THE LIQUID?

• COOLANT IS MADE UP OF A MIXTURE OF WATER AND ANTIFREEZE

COOLANTLETS GET THIS IN OUR NOTES

DAY THREE

LETS REVIEW• ENERGY

– ENERGY CONVERSION– TYPES OF ENERGY

• HEAT– WHAT IT IS AND HOW IT IS MEASURED– DIFFERENCES BETWEEN TEMP AND BTU

• WHY WE HAVE COOLING SYSTEMS• AIR COOLING

– TYPES– FINS, SHROUDS, AND FANS– MAINTENANCE

FOUR PURPOSES OF USING ANTIFREEZE

1. LOWER FREEZING POINT OF WATER

PURE WATER = 32F

25% ANTIFREEZE = 10F

50% ANTIFREEZE = -34F

68% ANTIFREEZE = -92F

PURE ANTIFREEZE = -10F



2. RAISE BOILING POINT OF WATER

WATER BOILS AT 212F

25% ANTIFREEZE BOILS AT 218F

50% ANTIFREEZE BOILS AT 225F

PURE ANTIFREEZE BOILS AT 320F




3. PREVENT RUST/CORROSION AND DEPOSITS

IS AN ADDITIVE THAT EVENTUALLY NEEDS REPLACED

RUST/CORROSION AND DEPOSIT SLOW DOWN THE HEAT TRANSFER

ACTS AS A BLANKET




3. PREVENT RUST/CORROSION AND DEPOSITS


4. LUBRICATES WATER PUMP SEAL


THERE ARE DIFFERENT KINDS OF COOLANT

• GREEN (CONVENTIONAL)– RECOMMENDED TO BE CHANGED

ONCE A YEAR

• PINK (DEX COOL)– RECOMMENDED TO BE CHANGED

EVERY 5 YEARS (SOME PROBLEMS)

• ORANGE

DON’T MIX DIFFERENT KINDS

DISPOSE OF PROPERLYSMELLS SWEETCHILDREN AND ANIMALS WILL DRINKIS TOXIC

COMPONENTSLETS GET THESE IN OUR NOTES UNDER LIQUID COOLING

• WATER JACKETS– PASSAGES MADE (CAST) INTO CYLINDER

BLOCKS AND HEADS– SPACES WHERE COOLANT FLOWS

•CAUSES COOLANT TO FLOW•USUALLY DRIVEN BY BELT FROM CRANK•SHAFT SUPPORTED BY BEARNING•SEAL PREVENTS COOLANT LEAKAGE

WATER PUMP

WEEP HOLE TO PREVENT LEAKING COOLANT AWAY FROM BEARING

OVER TIGHTING BELT WILL CAUSE BEARING FAILURE

UNDER TIGHTING WILL CAUSE BELT SLIPAGEENGINE OVER HEAT WILL RESULTBELT FAILURE WILL RESULT

RADIATORS

DAY FOUR

LETS REVIEW• AIR COOLING

• LIQUID COOLING– COOLANT

• PURPOSES OF ANTIFREEZE• HOW TO HANDLE

– WATER JACKETS– WATER PUMPS

HAVE LARGE SURFACE AREA FOR HEAT TRANSFER. FINS ON RADIATOR ADD SURFACE AREA FOR HEAT TRANSFER. COOLANTUSUALLY TRAVELS FROM TOP TO BOTTOM.

PRESSURE CAPS

SEALS COOLING SYSTEMTO ALLOW PRESSURE

TO FORM FROM EXPANDINGCOOLANT

PRESSURE RAISES BOILINGPOINT OF WATER

1 LB OF PRESSURE RAISESBOILING POINT 3 DEGRES F

PREVENTS A VACUUM FROMFORMING AS COOLANT

COOLS AFTER SHUT DOWN

WARNING! WARNING! WARNING!

NEVER REMOVE CAP FROM HOT RADIATOR

PRESSURE CAP OPERATION

SEALING, COOLANT HEATING AND EXPANDINGCREATING PRESSURE

PRESSURE EXCEEDESSPRING, VALVE OPENSAIR AND COOLANT LEAVEOVERFLOW TUBE

AS COOLANT LOSSES TEMPERATUREIT CONTRACTS. A VACUUM IS PREVENTED

SO RADIATOR AND HOSES WON’T COLLAPSE.

ALLOWS COOLING SYSTEM TO REMAIN FULL AT ALLTIMES. PREVENTS CORROSION AND ALLOWS CHECKINGOF COOLANT LEVEL WITHOUT REMOVING CAP.

CAP FORRECOVERY

SYSTEM HAS TOHAVE TWO SEALS.

THERMOSTAT OPERATION

NOTE! WATER PUMP CIRCULATES ANYTIME ENGINE IS RUNNING

ENGINE UP TO TEMPERATURE

WAX PELLET EXPANDSPUSHING VALVE OPEN.

VALVE OPEN, COOLANTCAN FLOW TO RADIATOR

TO COOL.

THERMOSTAT NOTES

• CLOSED = COOLANT TRAPED IN ENGINE, GETS HOT

• OPEN = COOLANT CAN FLOW TO RADIATOR TO COOL

• ALLOWS JUST THE RIGHT AMOUNT TO FLOW TO KEEP EVEN TEMPERATURE

• MOST MODERN VEHICLES CALL FOR 195 F.

• USED TO BE AS LOW AS 140 F.• MORE HEAT = MORE POWER

AND GAS MILAGE (BTU’s)

• STUCK CLOSED– ENGINE OVERHEATS

• STUCK OPEN– LESS POWER– LESS EFFIENCY (MPG)– CONTAMINATED OIL– MORE EMISSIONS– HEATER BLOWING COLD

AIR

DAY FIVE

HEATER CORE• HOW WE HEAT PASSENGER

COMPARTMENT– CONTROLLING HEAT

• HEATER CONTROL VALVE

• BLEND DOOR

– LEAKS– LOSS OF HEAT

• THERMOSTAT STUCK OPEN

• PLUGGED

• LOW COOLANT LEVEL / NO FLOW

SOFT PLUGS

• ALSO CALLED– FREEZE PLUGS– EXPANSION PLUGS– SAND PLUGS– CORE PLUGS

• LEAKS

• CHANGING

HOSES• TYPES

– PRE-FORMED– FLEX

• SPRINGS• WHEN TO CHANGE

– HARD– SOFT– BULGING– BEFORE THEY BREAK

• RECOMMENDED EVERY 6 YEARS

FANS• PURPOSE

– PROVIDE AIR FLOW THRU RADIATOR AT LOW SPEEDS. NOT NEEDED AT HIGH SPEEDS

• TYPES– SOLID– ENERGY CONSERVING

• FLEX

• CLUTCH

• ELECTRIC

ONE MORE TIME, COMPONENTS OF THE LIQUIDCOOLING SYSTEM.

TOOLS

• HYDROMETER

• BELT TENSION GAUGE

• PRESSURE TESTER

• THERMOMETER

• Ph TEST STRIPS OR METER

THAT’S ALL

cooling systems auto 1 if you did your homework, this will make more sense! if you didn’t, get it...

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