chap17 pps Automotive technology at University of Cambridge

This means that any oil or air filter, spark plug, or other service part can be used unless the vehicle manufacturer furnishes these parts for free during the warranty period.. This mean

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start

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certification test content area “A” (General

Engine Diagnosis) and content area “D”

(Lubrication and Cooling Systems Diagnosis

and Repair).

nuts using a torque wrench and the proper

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• Describe the proper procedure for changing

the engine oil and performing complete

chassis system lubrication and under-vehicle

inspection.

often required to perform routine service

operations It is the purpose of this chapter to

introduce the reader to these various service

procedures.

OBJECTIVES:

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air filter • alamite fittings • algorithm • American

Petroleum Institute (API) • American Society for Testing

Materials (ASTM)

antidrainback valve • Association des Constructeurs

Européens d’Automobiles (ACEA) • automatic

transmission fluid (ATF) • brake fluid • bypass

cabin filter • dipstick • DOT 3 • DOT 4 • DOT 5 • National

Lubricating Grease Institute (NLGI) • penetration test •

polyglycol • serpentine

(Poly V) • silicone brake fluid • syncromesh transmission fluid (STF) • viscosity • winter (W) • Zerk fittings

KEY TERMS:

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GETTING READY FOR SERVICE

Before service work is done, protect the vehicle inside by using

commercially available plastic or paper protective coverings for

seats, floor, and steering wheel.

As stated in the Hippocratic oath, a doctor agrees first to do no harm to the patient during treatment Service technicians should also try to do no harm

to the vehicle while it is being serviced.

As stated in the Hippocratic oath, a doctor agrees first to do no harm to the patient during treatment Service technicians should also try to do no harm

to the vehicle while it is being serviced.

Do No Harm

The hood must be opened, and often struts holding a hood are weak

or defective Therefore, always make sure the hood is securely held Connect an exhaust system hose to the tailpipe(s) before work is

started that will involve operating the engine.

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Figure 17–1 Before service

begins be sure to cover the

seats, floor, and steering

wheel with protective covering.

Figure 17–2 An exhaust hose should be connected to the tailpipe(s) whenever the engine is being run indoors.

Continued

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The Magnuson-Moss Act was passed into law in 1975 and allows the use

of nonoriginal equipment replacement parts during the service or repair of

a vehicle without losing the factory warranty This means that any oil or air filter, spark plug, or other service part can be used unless the vehicle manufacturer furnishes these parts for free during the warranty period The vehicle manufacturer cannot deny paying a warranty claim for a fault unless the replacement part is proved to be the cause of the condition needed to be covered by the warranty Therefore, it is up to the business owner, service manager, or the technician to determine if the replacement part is of good quality While this is very difficult or impossible, unless defects are obviously visible, the best solution is to use the original equipment manufacturer (OEM) parts or service parts from a well-known company.

The Magnuson-Moss Act was passed into law in 1975 and allows the use

of nonoriginal equipment replacement parts during the service or repair of

a vehicle without losing the factory warranty This means that any oil or air filter, spark plug, or other service part can be used unless the vehicle manufacturer furnishes these parts for free during the warranty period The vehicle manufacturer cannot deny paying a warranty claim for a fault unless the replacement part is proved to be the cause of the condition needed to be covered by the warranty Therefore, it is up to the business owner, service manager, or the technician to determine if the replacement part is of good quality While this is very difficult or impossible, unless defects are obviously visible, the best solution is to use the original equipment manufacturer (OEM) parts or service parts from a well-known company.

What is the Magnuson-Moss Act?

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WIPER BLADE INSPECTION & REPLACEMENT

Windshield wiper blades are constructed of rubber and tend to

become brittle due to age Wiper blades should be cleaned

whenever the vehicle is cleaned using water and a soft cloth

Continued

Figure 17–3 Installing a wiper

blade insert into a wiper arm.

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Wiper blade or blade insert replacement includes:

Turn the ignition switch to on (run).

Turn the wiper switch on and operate the wipers.

When the wipers are located in an easy-to-reach location, turn

the ignition switch off The wipers should stop.

Remove the insert or the entire arm as per the instructions on

the replacement windshield wiper blade package.

After double-checking that the wiper is securely attached, turn

the ignition switch on (run).

Turn the wiper switch off and allow the wipers to reach the

park position Check for proper operation.

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CABIN AND AIR FILTER REPLACEMENT

A cabin filter is used in heating, ventilation, and air-conditioning

(HVAC) systems in the outside air passage Some could include

activated charcoal to eliminate odors The cabin air filter should be changed about every two years or every 24,000 miles (39,000 km) The cabin filter can be accessed from:

Under the hood at the cowl (bulkhead)

Under the dash, usually behind the glove (instrument panel)

compartment

Figure 17–4 A cabin filter can be

accessed either through the glove

compartment or under the hood on

most vehicles.

Continued

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Figure 17–5 (a) A typical dirty air filter (b) Always check the inlet passage leading to the air filter for debris that can reduce airflow to the engine.

(a)

An air filter filters dirt

from the air before it enters the intake system It should

be replaced according to manufacturer’s

recommendations.

Many recommend replacing

the filter every 30,000 miles

(50,000 km) or even more

frequently under dusty

conditions Many techs

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BRAKE FLUID LEVEL INSPECTION

Brake fluid transmits the force of the driver’s foot on the brake

pedal to each individual wheel brake It should be checked when

engine oil is changed (every 3,000 miles [4,800 km] or every three months, whichever occurs first) Two types of master cylinders:

Transparent Reservoir Allows viewing of brake fluid (and

hydraulic clutch master cylinder if so equipped) without

having to remove the cover of the reservoir The level should

be between the MIN (minimum) level indicated and the MAX

(maximum) level indicated on the clear plastic reservoir

Metal or Nontransparent Plastic Reservoir Used on older

vehicles; requires the cover be removed to check the fluid

level The level of fluid should be 1/4”(6 mm) from the top.

Continued

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Figure 17–6

A master brake cylinder with transparent reservoir The brake fluid should be between the “MAX” and “MIN” levels indicated on the reservoir.

CAUTION: Do not overfill a brake master cylinder The brake fluid gets

hotter as the brakes are used and there must be room in the master cylinder reservoir for the brake fluid to expand.

CAUTION: Do not overfill a brake master cylinder The brake fluid gets hotter as the brakes are used and there must be room in the master cylinder reservoir for the brake fluid to expand.

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Figure 17–7 DOT 3 brake fluid Always use brake fluid from a sealed container because the

fluid absorbs moisture from the air Such contaminated brake fluid has a lower boiling point

and can cause rust to form in the brake system components.

BRAKE FLUID TYPES

Continued

Brake fluid is made from a combination

of various types of glycol, which is a

non-petroleum-based fluid It is a

polyalkylene-glycol ether mixture

called polyglycol.

All polyglycol brake fluid is

clear to amber in color.

All brake fluid must meet Federal Motor

Vehicle Safety Standard 116 The SAE

and DOT have established brake fluid

specification standards.

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Dot 3 The brake fluid most often used is DOT 3 It can absorb

2% of its volume in water per year Moisture is absorbed by the

brake fluid through microscopic seams in the brake system and

around seals.

Over time, water will corrode the system and thicken brake fluid

The moisture also can cause a spongy brake pedal action due to

reduced vapor-lock temperature.

CAUTION: DOT 3 brake fluid is a very strong solvent and can remove

paint! Care is required when working with DOT 3 brake fluid to avoid

contact with the vehicle’s painted surfaces It also takes the color out of

leather shoes.

CAUTION: DOT 3 brake fluid is a very strong solvent and can remove

paint! Care is required when working with DOT 3 brake fluid to avoid

contact with the vehicle’s painted surfaces It also takes the color out of

leather shoes.

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Dot 4 Formulated for use by all vehicles, imported or domestic is

type DOT 4 brake fluid Commonly called LMA (low moisture

absorption) because it does not absorb water as fast as DOT 3

The cost of DOT 4 is approximately double the cost of DOT 3.

Dot 5 Commonly called silicone brake fluid, DOT 5 is made

from polydimethylsiloxanes It does not absorb water and is called nonhygroscopic DOT 5 fluid does not mix with DOT 3 or DOT 4

brake fluids DOT 5 brake fluid is purple ( violet ) in color

NOTE: Even though DOT 5 does not normally absorb water, it is still

tested using standardized SAE procedures in a humidity chamber After a

fixed amount of time, the brake fluid is measured for boiling point Since it

has had a chance to absorb moisture, the boiling point after this sequence

is called the minimum wet boiling point.

NOTE: Even though DOT 5 does not normally absorb water, it is still

tested using standardized SAE procedures in a humidity chamber After a

fixed amount of time, the brake fluid is measured for boiling point Since it

has had a chance to absorb moisture, the boiling point after this sequence

is called the minimum wet boiling point.

Continued

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Dot 5.1 A non-silicone-based polyglycol fluid, DOT 5.1 is clear

to amber in color This severe duty fluid has a boiling point of

over 500°F, equal to the boiling point of silicone-based DOT 5

fluid Unlike DOT 5, DOT 5.1 can be mixed with DOT 3 or DOT

4 according to the brake fluid manufacturer’s recommendations.

CAUTION: Some vehicle manufacturers such as Chrysler do not

recommend the use of or the mixing of other types of polyglycol brake

fluid and specify the use of DOT 3 brake fluid only Always follow the

CAUTION: Some vehicle manufacturers such as Chrysler do not

recommend the use of or the mixing of other types of polyglycol brake

fluid and specify the use of DOT 3 brake fluid only Always follow the

Brake Fluid Boiling

Points

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ENGINE OIL LEVEL AND CONDITION

The oil level should be checked with the vehicle is on level

ground and after the engine has been off for several minutes

Remove the oil level indicator, called a dipstick, wipe the oil

off, and reinsert it all the way down

Figure 17–8 A typical engine oil

level indicator (dipstick).

Continued

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Once again remove the dipstick and check where the oil level

touches the indicator The “add” mark is usually at the one quart

low point If oil needs added, use the proper oil and add to the

engine through the oil fill opening

Figure 17–9 The oil level should read no higher than the “MAX” level and no lower than the

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ENGINE OIL CHANGES

Most experts recommend that engine oil be replaced and a new

filter installed every 3,000 miles (4,800 km) or three months

Most vehicle manufacturers recommend that the oil be changed

according to a “normal” or “severe use” schedule.

See this chart on

Page 123 of your

textbook.

Continued

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VISCOSITY OF OIL (SAE RATING)

The word viscosity means resistance to flow An oil with a high

viscosity has a higher resistance to flow and is thicker than a viscosity oil.

lower-Oil is tested and assigned a viscosity number according to standards

by the SAE Tested at two different temperatures, it is assigned a

number based on flow characteristics Thin oil is assigned a lower

number and thicker oil is a higher number.

Oil tested at 0°F (-18°C) has the letter W after its number The W

represents winter For example, a SAE 10W engine oil was tested

at 0°F and assigned a thickness rating of 10 Oil tested at 212°F

(100°C) has no letter after its number SAE 30 oil is tested at 212°F.

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Multi-Viscosity Engine Oils Viscosity index (VI) improvers can

be added to engine oil to prevent it from becoming thin at higher

temperatures.

For example, SAE 5W oil with the VI improvers added can be rated

as a SAE 30 when tested at 212°F Because of the wide range of

temperatures at which this oil can function, multi-viscosity oils such

as 5W-30 and 10W-30 are often the only oils recommended for use.

Continued

NOTE: Some vehicle manufacturers such as Ford and Honda recommend

the exclusive use of SAE 5W-20 or SAE 0W-20 engine oil The owner’s

manual warns that this is the only viscosity that is acceptable to use under

all temperatures and operating conditions Always follow the vehicle

manufacturer’s recommended engine oil and viscosity.

NOTE: Some vehicle manufacturers such as Ford and Honda recommend

the exclusive use of SAE 5W-20 or SAE 0W-20 engine oil The owner’s

manual warns that this is the only viscosity that is acceptable to use under

all temperatures and operating conditions Always follow the vehicle

manufacturer’s recommended engine oil and viscosity.

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QUALITY OF OIL (API RATING)

Although generally difficult to purchase low-quality oil, it is

possible to select the incorrect grade for the intended application.

The quality rating is established by test procedures set up by the

American Petroleum Institute (API), formerly the American

Society for Testing and Materials (ASTM), with the cooperation

of the SAE.

In gasoline engine oil ratings, the letter “S” means service, but it

can be remembered as standing for oil to be used in spark ignition

engines.

The rating system is open-ended, so newer, improved ratings can

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Diesel classifications begin

with the letter

“C”, which stands for

commercial, but can

also stand for oil to be

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ILSAC OIL RATING

The International Lubricant Standardization and Approval

Committee (ILSAC) developed an oil rating that consolidates

the SAE viscosity rating and the API quality rating

If an engine oil meets the standards,

a “starburst” symbol is displayed on the front of the oil container.

The original GF-1 (gasoline fueled) rating was updated to GF-2 in 1997,

to GF-3 in 2001, and GF-4 in 2004

Figure 17–11 The International Lubricant Standardization and Approval Committee (ILSAC)

starburst symbol This symbol is on the front of the container means the oil is acceptable for

use in almost any gasoline engine.

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How Does an Oil Life Monitor Work?

1 Vehicle mileage The most commonly used vehicle service monitoring

system When a certain number of miles has occurred since it was reset,

the control (usually the power train control module—PCM) will turn on a

dash light that states that maintenance is required.

2 Oil life computer program A computer program is used to determine

the life of the engine oil For example, when the oil change warning light

is reset, the oil life is reset to 100% Then the power train control module

(PCM) tracks the number of engine starts, outside temperature, intake air temperature (IAT) sensor input, as well as miles traveled Because long

drives are easier on engine oil than short stop-and-go driving, the PCM

deducts numbers faster during this condition.

While some manufacturers such as Mercedes, use a sensor to measure

oil temperature, most vehicle oil change monitors function two ways:

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SYNTHETIC ENGINE OIL

According to SAE publications, engine oil is classified into groups:

Group I—Mineral, nonsynthetic, base oil with few if any

additives Suitable for light lubricating and rust protection;

not to be used in an engine.

Group II—Mineral oils with quality additive packages.

Most of the conventional engine oils are Group II.

Group III—Hydrogenated (hydroisomerized) synthetic

compounds commonly referred to as hydrowaxes or

hydrocracked oil The lowest cost synthetic engine oils, such

as Castrol Syntec.

Continued

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Group IV—Synthetic oils made from mineral oil and

monomolecular oil called polyalphaolefin or PAO Mobil 1 is an

example of a Group IV synthetic oil.

Group V—Non-mineral sources such as alcohol from corn

called diesters or polyolesters An example is Red Line synthetic.

Figure 17–12

Mobil 1 synthetic engine oil is used by

several vehicle manufacturers in new

engines.

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Groups III, IV, and V are all considered to be synthetic because the molecular structure of the finished product does not occur naturally and is man-made through chemical processes.

All synthetic engine oils perform better than Group II (mineral) oils especially when tested to the Noack Volatility Test ASTM D-5800 This procedure measures the ability of an oil to stay in grade after

being heated to 300°F (150°C) for one hour.

The oil is measured for percentage of weight loss As the lighter

components boil off, the viscosity will increase If you start with an SAE 5W oil, it could test as a 15W or even 20W the end of the test

It is important that the oil you buy stays in grade for the proper

lubrication of your engine.

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Most 4-cycle lawn and garden equipment engines are air cooled and

operate hotter than many liquid cooled engines Lawn mowers and other

small engines are often operated near or at maximum speed and power

output for hours at a time These operating conditions are hard on any

engine oil Try using a synthetic oil The cost is not as big a factor because most small 4-cycle lawn mower engines require only about 1/2 quart ( 1/2

liter) of oil The synthetic oil is able to perform under high temperatures

Most 4-cycle lawn and garden equipment engines are air cooled and

operate hotter than many liquid cooled engines Lawn mowers and other

small engines are often operated near or at maximum speed and power

output for hours at a time These operating conditions are hard on any

engine oil Try using a synthetic oil The cost is not as big a factor because most small 4-cycle lawn mower engines require only about 1/2 quart ( 1/2

liter) of oil The synthetic oil is able to perform under high temperatures

Use Synthetic Engine Oil in Lawn Equipment

An advantage of using synthetic engine oil is ability to remain fluid

at very low temperatures This characteristic of makes it popular in

climates where cold-engine cranking is important.

A major disadvantage is cost Synthetic engine oils can cost four or five times as much as Group II mineral engine oils Some synthetics

are blended with Group II oils and must be labeled blends.

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EUROPEAN OIL RATING SYSTEM

Association des Constructeurs

Européens d’Automobiles

(ACEA) rates oil:

See these charts on Page 125

of your textbook.

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Some oils can meet the industry specifications, such as SAE, API, and/or

ILSAC ratings, but not pass the tests specified by the manufacturer The

standard should meet those of the manufacturer, which include:

Some oils can meet the industry specifications, such as SAE, API, and/or

ILSAC ratings, but not pass the tests specified by the manufacturer The

standard should meet those of the manufacturer, which include:

Make Sure the Oil Meets Specific Vehicle Specifications

BMW—Longlife 98 and longlife-01 (abbreviated LL-01), LL-04

General Motors—GM 6094M, GM 4718M (synthetic oil specification)

General Motors—GM LL-A-25 (gasoline engines) & GM LL-B-25 for

GM vehicles equipped with diesel or European-built engines

Ford—WSS-M2C153-H, WSS-M2C929-A (low viscosity rating—

SAE 5W-20), WSS-M2C930-A, WSS-M2C931-A, and WSS-M2C934-A

Chrysler—MS-6395 (2005 vehicles, MS-10725

Mercedes—229.3, 229.5, 229.1, 229.3, 229-31, 229.5, and 229.51

Volkswagen (VW & Audi)—502.00, 505.00, 505.01, 503, 503.01, 505,

506 diesel, 506.1 diesel, and 507 diesel

Honda—HTO-06

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ENGINE OIL DISPOSAL

All used engine oil should be disposed or recycled according to

federal, state, or local rules and regulations Used engine oil is

considered hazardous due to dissolved metals and acids created

in an operating engine.

Vehicle owners often forget when they last changed the oil This is

particularly true of the person who owns or is responsible for several

vehicles A helpful method for remembering when the oil should be

changed is to change the oil at the start of each season of the year.

Remembering that the oil needs to be changed on these dates helps

owners budget for the expense and the time needed.

Vehicle owners often forget when they last changed the oil This is

particularly true of the person who owns or is responsible for several

vehicles A helpful method for remembering when the oil should be

changed is to change the oil at the start of each season of the year.

Remembering that the oil needs to be changed on these dates helps

owners budget for the expense and the time needed.

Follow the Seasons

• Fall

• Winter

(September 21) (December 21)

• Spring

• Summer

(March 21) (June 21)

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Figure 17–14 A cutaway of a typical spin-on oil filter Engine oil enters the filter through the small

OIL FILTERS

Oil is pumped from the oil pan through the filter before it goes

into the lubricating system passages The filter is made from

either closely packed cloth fibers or a porous paper.

These particles are so small they can flow through the bearing oil film and not touch the surfaces, and so do no damage

Large particles are trapped by the filter while microscopic particles will flow through the filter pores.

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Many oil filters are equipped with an antidrainback valve that prevents oil

from draining out of the filter when the engine is shut off This valve keeps oil

in the filter and allows the engine to receive immediate lubrication as soon as

the engine starts.

Continued

Figure 17–15 A rubber diaphragm acts as an antidrainback valve to keep the oil in the filter

when the engine is stopped and the oil pressure drops to zero.

The engine or filter has a bypass that

will allow oil to go around the filter

element It allows the engine to be

lubricated with dirty oil, rather than

having no lubrication, if the filter

becomes plugged

The oil also goes through the bypass

when the oil is cold and thick.

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Many persons believe oil filters will remove all dirt from the oil being

circulated through the filtering material Most will filter particles that are

about 10 to 20 microns in size A micron is a millionth of a meter, or

0.000039 inch Most dirt and carbon particles that turn engine oil black are less than a micron in size In other words, it takes about 3,000,000 (three

million) of these carbon particles to cover a pinhead To help visualize how small a micron is: a typical human hair is 60 microns in diameter In fact,

anything smaller than 40 microns is not visible to the human eye

Dispersants are added to engine oil to prevent dirt from adhering together

to form sludge It is the same dispersant additive that prevents dirt from

being filtered or removed by other means If an oil filter could filter particles down to one micron in size, the engine would not receive sufficient oil

through the filter for lubrication Oil recycling companies use special

chemicals to break down dispersants, which permits dirt in the oil to