MAHLE RTI Laser 4 User Manual

®

Laser 4

®

Laser 4 Plus

OPERATION MANUAL

Four Wheel Alignment

RTI Technologies, Inc.

York, PA 17402

800-468-2321 (Ext. 259)

Manual No. 040-80152-00

TABLE OF CONTENTS

Four Wheel Alignment, Basics...................3

Pre-Alignment Checks .........................4

Four Wheel Alignment Procedures

Install Wheel Clamps .....................5

Compensating Wheel Runout ...............5

Camber Reading .........................7

Caster Reading ..........................9

Steering Axis Inclination (SAI) Reading.....11

Instrumentation Set-up ...................13

Front Wheel Toe Reading ................14

Front Wheel Alignment to Vehicle Centerline 16

Thrust Angle Alignment..................17

Total Vehicle Four Wheel Alignment .......18

Calibration Procedure.........................19

Battery Replacement ..........................22

CONGRATULATIONS: You have purchased one of the finest Four-wheel Alignment Systems available at

any price.
Fill out and return the Warranty Card within 90 days to activate the warranty and

free lifetime technical support.

Laser 4 & Laser 4 Plus - Instrumentation Only

Factory Technical Support

( 8 AM to 5 PM Eastern )

800-468-2321

(Consult the shop manual concerning methods for making alignment adjustments.)

Page 1

The Laser 4 Plus is a four-wheel alignment system t h a t uses three Class II laser products. These lasers have a
maximum output power of 5.0 milliwatts. The laser tubes meet all government safety standards, although
common sense dictates that one should not stare directly into the beam. Laser precision is unaffected by light,
temperature, and the concentrated light beam is clearly visible anywhere. The following precautions have been
taken to insure the safety of the system (See Fig. 1):

1) Serial Number label is located on underside of casting on power supply cover. Each serial number is
recorded for future identification.

2) LED light comes on as soon as power is activated to laser beam.

3) Slide cover must be slid toward casting to uncover laser beam (LH Toe Gauge only).

4) Caution decals are located on the unit.

5) Flip-open protective cap protects laser unit when not in use.

CAUTION: Use of controls or adjustments or performance of procedures other than those specified herein

may result in hazardous radiation exposure.

Page 2

FOUR WHEEL ALIGNMENT

Rear wheels must track and foll ow the front wheels in
a parallel direction with all four wheel adjusted to the
common centerline of the vehicle. (See Fig. 2)

1)Front wheel alignment and

front wheel toe on car
manufacturer’s
specifications.

2)Rear wheel alignment and
rear wheel toe on car
manufacturer’s
specifications.

3)Front wheels track to rear
wheel thrust lines and to
centerline of vehicle.

4)Steering wheel centered in
straight ahead position.

BASIC STEPS TO DO FOUR WHEEL ALIGNMENTS

Step 1
Adjust front wheel camber and caster to car manufacturer’s

settings. (See Fig. 3)

Step 2
Center steering wheel. Adjust front wheel toe to

manufacturer’s setting. (See Fig.4)

Step 3
Adjust f ront wheels to rear wheel in relation to rear axle

position. (See Fig. 5)

Step 4
Adjust rear wheel camber and toe to car manufacturer’s

setting.

Page 3

PRE-ALIGNMENT CHECKS

To mai ntain a true alignme nt job; ensure maximum tire mileage a nd steering safety , it is important to p erfor m
certain pre-alignment checks before doing wheel alignment adjustments. They are:

1. Inflate tires to proper inflation pressures.

2. Check car spring height.

3. Check shock absorbers and struts.

4. Inspect steering/suspension parts for wear or looseness. Replace
parts which are worn beyond manufacturer’s accepted tolerances.

5. Check calibrations of the Laser 4 wheel alignment equipment. See
Calibration Procedure section of this manual.

FRONT WHEEL SETBACK

Front wheel setback is a condition in which
one front wheel has been driven or pushed
back, out of alignment, from the opposite
wheel. It is caused by one wheel of the vehicle
striking a curb or pothole in the road forcing
that wheel back from the other (See Fig. A).

To measure front wheel setback with the Laser
4 wheel alignment system, adjust front wheel
toe; center steering wheel, and note the
location of the Laser beam on the wheel
setback scale (See Fig. B) of the passenger side
laser toe gauge. Make sure that the Laser toe
gauges are centered on the wheel clamps. The
scale reads eith er right or left wheel setback.
The front wheel suspension should be adjusted
if the setback is greater than 1/4 inch.
Excessive front wheel setback will cause a
change in caster.

The Laser 4 alignment system automatically
compensates for front wheel setback because
of the use of the tapered, precisely ground
magnets. When toe is adjuste d to zero, the tube
of the optical toe gauges become parallel to
each other. Front wheel toe reading is
unaffected by front wheel setback.

Page 4

INSTALL WHEEL CLAMPS

Install Wheel Clamps on each wheel. (See Fig. 6) Adjust
the four bars in each clamp for t he best fit to the wheel
rim. Two sets of notches on one end or a threaded pin on
the other end provide for inside or outside mounting to the
wheel rim. Use d ouble-sided foam tape at contact points
on decorative or soft metal rims. Make sure that th e Wheel
Clamps are securely attached.

Select th e configuration which gives the most secure fit
with the least amount of pressure on the wheel rim.

COMPENSATING WHEEL RUNOUT (Laser 4 Plus)

Wheel Clamps must be adjusted to compensate for wheel
runout. This adjustment is made using the three Runout
Adjusting Knobs.

1) Raise wheel and tire from turning gauge or rear wheel
slip plate. Turn wheel so the large wheel clamping
knob is at the top (12 o’clock position).

2) Mount the Electronic Gauge on the Wheel Clamp as
shown (See Fig.7). Center the magnet on the Wheel
Runout Compensating Adapter. Turn the Electronic
Gauge so it is level.

3) Set the selector to CASTER and press the rocker
switch to ON. Press the Zero Button. (See Fig. 8)

4) Rotate the wheel so the wheel clamp adjusting knob
is at the 2 o’clock position. Turn the El ectronic gauge
so it is once ag ain level. Note the value on the Digital
Readout Screen. Ignore the + or - which appears
before the numbers.

Repeat at the 4, 6, 8, and 10 o’clock positions. Re­level the Electronic gauge at each position.

5) Turn the wheel to the position where the largest
numeric reading was observed. Turn the Runout
Adjusting Knobs to decrease this reading by one -half.
Press the Zero Button and repeat step 4, checking for
the largest numeric reading at each of the six
positions.

6) The wheel clamp is properly adjusted when the
Electronic Gauge reads within 0.1 at all six positions.

Page 5

COMPENSATING WHEEL RUNOUT (Laser 4)

Wheel Clamps must be adjusted to compensate for wheel
runout. This adjustment is made using the three Wheel
Runout Adjusting Knobs.

1) Raise wheel and tire from turning gauge or rear wheel
slip plate. Turn wheel so the large wheel clam ping
knob is at the top (12 o’clock position).

2) Mount t he Spirit Level Gauge on the Wheel Clamp.
(See Figure 9) Center the magnet on the Wheel
Runout Compensating Adapter. Turn the Spirit L evel
Gauge so it is level.

3) Zero the Caster Spirit Level using the adjusting knob
on the bottom of the unit.

4) Rotate the wheel so the wheel clamp adjusting knob
is at the 2 o’clock position. Turn the Spirit Level
Gauge so it is once again level. Note the amount of
movement of the bubble away from zero.

Repeat at the 4, 6, 8, and 10 o’clock positions. Re­level the Spirit Level Gauge at each position.

5) Turn the wheel to the position where the largest
movement of the bubble was observed. Turn the
Runout Adjusting Knobs to decrease this reading by
one-half. Zero the Caster Spirit Level and repeat step
4, checking for the largest movement of the bubble
away from zero at each of the six positions.

6) The wheel clamp is properly adjusted when the
bubble does not move away from zero at all six
positions.

Page 6