Laser 4212 User manual

4212

Instructions
Cam Belt Tensioner Gauge
Measure the tension on most cam belts

LASER TOOLS Cam Belt Tensioner Gauge 3
The electronic belt tension gauge can be used to measure
and adjust the tension of timing and auxiliary belts fitted to
motor vehicles and other machines.
Tension can be displayed in a variety of standard and
manufacturers’ units. Tension limits can be programmed into
the instrument, either manually or automatically.
During belt tension measurement and adjustment, the belt
tension is displayed. A visual and audible indication of
whether the tension is within or outside the set limits is also
given. This avoids the user having to read the display whilst
adjusting the belt.
The selected tension limits, measurement units and calibration
parameters are stored in a non-volatile memory, and will be
remembered even when the instrument is switched off and
the batteries removed.
Note: Tension checking should always be carried out in
accordance with the vehicle manufacturers’ instructions.
BMW | FORD | ROVER | SEAT | VAG | VAUXHALL | VOLVO
KILOGRAMS | LOWENER | NEWTONS | PEISELER
POUNDS | SEEM
Introduction
Measurement Units
CCoonntteennttss
Introduction Page 3
Principle of operation Page 4
Controls and indicators Page 4
Precautions Page 5
Operation Page 5
Getting the best results Page 8
Menus Page 8
Calibration Page 9
Auto power off Page 10
Low battery warning Page 10
Maintenance Page 10
Warranty procedure Page 10
Specification Page 11

LASER TOOLS Cam Belt Tensioner Gauge
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The measuring head is placed on the belt and the clamp is
tightened using the clamping knob. This deflects the belt
through a known angle defined by the anvil and the fixed
pillars. A load cell attached to the clamp measures the force
required to deflect the belt, which is proportional to the
tension in the belt. The output voltage from the load cell is
digitised and scaled to give the correct tension reading on the
instrument display.
The main unit has a 16-character liquid crystal display, three
indicator LED’s, a beeper, and a keypad with five keys.
The display is used for setting up the instrument and
displaying the measured tension. To avoid the user having to
read the display whilst adjusting the belt, the beeper and
LED’s give an audible and visual indication of whether the
tension is within or outside the preset limits.
Four of the five keys on the keypad have dual functions:
The ‘I’ key switches on the instrument. During operation of the
instrument, it functions as an ‘ENTER’ key.
The ‘SET’ key switches the instrument from measurement
mode to setting mode. It also functions as an ‘UP’ key to
increment a value or scroll up through a menu.
The ‘ZERO’ key switches the instrument from measurement
mode to zero mode. It also functions as a ‘DOWN’ key to
decrement a value or scroll down through a menu.
The ‘MENU’ key puts the instrument into ‘MENU’ mode, or
exits from it if a menu operation is not required. In some
operating modes, pressing this key backs up one step in the
procedure.
The ‘0’ key switches off the instrument.
In measurement mode, the three LED’s and the beeper
indicate if the measured tension is below, within, or above the
pre-set limits. If the tension is low, the yellow LED will light
and the beeper will emit a single beep after each
measurement. If the tension is OK, the green LED will light
and the beeper will not sound. If the tension is high, the red
LED will light and the beeper will emit a double beep after
each measurement.
Principle of operation
Controls and indicators

LASER TOOLS Cam Belt Tensioner Gauge 5
1. This is a precision measuring instrument. To ensure
accurate results it is essential that the operating
procedure is correctly followed.
2. The instrument must only be used with the measuring
head with which it has been calibrated. When the unit is
supplied, the main unit and the measuring head will have
the same serial number, for example:
Main unit H101000
Measuring head H101000
3. If the instrument is used with a different measuring head,
it must be re-calibrated before using.
4. To avoid potential irreparable damage, never clamp the
measuring head onto a belt unless the head is plugged
in and the instrument is switched on.
5. The instrument warns of a head overload condition, but
is unable to if the head is unplugged or the instrument is
switched off.
6. Never clamp the measuring head onto an inflexible
object such as a metal or wooden bar.
7. Never drop the instrument or subject it to sharp impacts.
8. Never allow the instrument or measuring head to hang
by the connecting cable.
1. Before using the instrument for the first time, remove the
battery compartment cover, and fit four AA size 1.5V
alkaline batteries. Ensure that the batteries are inserted
correctly, as printed inside the battery compartment.
2. Plug the DIN connector of the measuring head into the
DIN socket of the main unit.
3. Switch on the instrument by pressing the ‘I’ key. The
three LED’s will flash for about two seconds whilst the
unit initialises. If the LED’s do not flash, then the batteries
may be flat or incorrectly fitted.
4. The message ‘LASER' will appear for one second.
5. This is followed by the message ‘DISPLAY CONTRAST’
then the prompt ‘LIGHT / DARK / OK
6. If the display is too light or too dark, the contrast may be
adjusted by pressing and holding down the key to
darken it, or the key to lighten it.
When the display contrast is OK, press the ‘*’key.
The display contrast is remembered when the instrument
is switched off, even if the batteries are removed.
Precautions
Operation
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LASER TOOLS Cam Belt Tensioner Gauge
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The contrast should not require further adjustment unless
there is a large change in temperature, or the batteries
are nearing the end of their life. If no display is visible,
check that the contrast has not been set too low.
8. After setting the contrast, the unit checks if the
measuring head is connected. If it is not, the message
‘HEAD MISSING!’ will be displayed and the LED’s
will flash.
9. This message will also be displayed if the head becomes
disconnected at any time during the setup and
measurement procedure.
10. The message ‘SET UNITS’ will be displayed for one
second, followed by the currently selected
measurement unit, for example: NEWTONS
11. Use the and keys to scroll up and down through
the alphabetical list of measurement units.
BMW | ROVER | FORD | SEAT | VAG |
VAUXHALL | VOLVO
KILOGRAMS FORCE SEEM | LOWENER UNITS
NEWTONS | PEISELER UNITS | POUNDS FORCE
12. When the required unit appears on the screen, press the
key to select them. The first time the instrument is
used, the default unit is Newtons. If the units are
changed, they will be remembered when the unit is
switched off, even if the batteries are removed.
13. Where applicable, the part number of the relevant
manufacturers’ tensioning tool will be displayed
alongside the measurement unit.
For example: ROVER KM4088AR
14. BMW tension settings are dependent on belt thickness
and cylinder head temperature. Therefore, to ensure
accuracy, the vehicle manufacturers’ tension checking
instructions MUST be followed.
15. After selecting the measurement units, the message
‘HIGH LIMIT: 250’ will be displayed. This shows the
currently set high limit for the tension measurement.
16. Use the and keys to increase or decrease the
tension to the required setting. Note: To make the setting
quicker, if a key is held down, the count will speed up
after about ten seconds.
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LASER TOOLS Cam Belt Tensioner Gauge 7
17. When the tension is correct, press the key to confirm
the setting. After setting the high limit, the message
‘LOW LIMIT: 200’ will appear. This shows the currently
set low limit for the tension measurement. The low limit is
displayed and set in the same way as the high limit.
(a) The first time the instrument is used, the default high and
low limits are 250 and 200 Newtons respectively.
(b) The maximum value to which the high limit can be set is
the maximum value that the unit will display in the
currently selected units (see Specifications).
(c) The maximum value to which the low limit can be set is
the high unit. The low limit cannot be set higher than the
high limit.
(d) If the measurement unit is changed, the previously
stored high limit is erased and replaced with the
maximum value for the selected unit. After setting the
limits, the message ‘TO ZERO, PRESS will be
displayed. At this point the measuring head should not
be clamped onto the belt, nor have any load applied to
it. Ensure that the clamping knob is fully unscrewed.
18. Press the key to zero the instrument.
19. Next, the message ‘MEASURE, PRESS
will be displayed.
20. Press the key to start the measurement.
21. To ensure that the tension applied to the belt is correctly
distributed, turn the crankshaft until the engine is in the
position that would be appropriate for valve timing
checking/belt replacement. This is normally TDC on the
compression stroke for No.1 or No.4 cylinder.
22. Slide the clamping hook of the measuring head over the
belt at the measurement position indicated by the vehicle
manufacturer, so that the edge of the belt touches the
two locating lugs. If no position is indicated, position the
measuring head in the centre of the longest free section
of the belt. Ensure that the clamping hook rests in the
‘trough’ between the belt teeth.
23. Turn the tensioning knob clockwise until the flat side of
the belt contacts the anvil, and the
24. knob is finger-tight. Do not over tighten.
NOTES:
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LASER TOOLS Cam Belt Tensioner Gauge
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825. If at any time whilst tightening the clamp, the three LED’s
illuminate, the beeper sounds continuously and the
message ‘WARNING-OVERLOAD’ appears on the
display, stop tightening the clamp immediately. If the
load exceeds 850 Newtons or the equivalent, the
message ‘HEAD DAMAGED’ will appear. If this happens,
the instrument must be returned to the manufacturer for
head replacement and re-calibration.
26. The display will now show the belt tension and the LED’s
and beeper will indicate if the measurement is within or
outside the limits. The yellow LED lights if the tension is
too low, and the beeper emits a single beep after each
measurement. The red LED lights if the tension is too
high, and the beeper emits a double beep.
27. If the tension is OK, the green LED lights and the If
necessary, adjust the belt tension until it is within limits.
Then re-check the tension as described in ‘Getting the
best results’.
28. If it is required to change the measurement unit, target
tension or limits, the instrument can be switched from
measuring mode to set mode by pressing the ‘SET’ key,
then setting the units, tension and limits, as described
from step 7.
The belt tension between the measuring points will vary as the
engine is rotated due to differing internal loads on the
crankshaft, camshaft etc. For this reason, it is recommended
that at least four measurements are taken with the crankshaft
turned to four different positions.
Do not forget to remove the measuring head before rotating
the crankshaft.
Always zero the instrument every ten minutes if the instrument
is being used for a long time.
Do not forget that the zeroing must be done with the
measuring head removed from the belt, and the clamp fully
unscrewed.
The instrument has the following menus, which can be
accessed at any time by pressing the ‘Menu’ key.
When menus are selected, the menu header will appear.
MENUS, PRESS
Use the and keys to scroll up and down through
the menu.
Getting the best results
Menus
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LASER TOOLS Cam Belt Tensioner Gauge 9
DISPLAY CONTRAST
RESTORE DEFAULTS
TURN BEEPER ON [OFF]
TURN LEDS ON [OFF]
Press the key to select the required option.
This performs the menu operation and returns to the menu
header screen, except for the calibration procedure, which
had several steps. To exit the menus without making a
selection, press the ‘Menu’ key again.
This allows the user to access the display contrast setting if it
requires adjustment at any time other than at switch-on. The
procedure for adjustment is the same as at switch-on.
This restores the following default settings:
Contrast
Units
Tension high limit
Tension low limit
50%
Newtons
250
200
When ‘TURN BEEPER ON’ is displayed, pressing the key
turns the beeper on for out of-limit indication.
When ‘TURN BEEPER OFF’ is displayed, pressing the key
turns the beeper off.
Note: The beeper always sounds to confirm a key press
or a fault condition.
When ‘TURN LEDS ON’ is displayed, pressing the key
turns the LED’s on for out-of limit indication. When ‘TURN
LEDS OFF’ is displayed, pressing the key turns the
LED’s off.
Note: The LED’s always light for a fault condition.
Calibration should be carried out after every 250 operations of
the unit, or at 6 month intervals.
After 220 operations the message ‘CAL. DUE: 30’ will be
displayed whenever the instrument is switched on. This
indicates that calibration will be due after the unit has been
switched on 30 more times. This figure will decrease every
time the unit is switched on. After 250 operations, the
message ‘CAL. OVERDUE: 01’ will be displayed whenever
the instrument is switched on.
CALIBRATION
DISPLAY CONTRAST
RESTORE DEFAULTS
TURN BEEPER ON [OFF]
TURN LEDS ON [OFF]
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LASER TOOLS Cam Belt Tensioner Gauge
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This will not prevent use of the instrument, but calibration
should be carried out as soon as possible.
FAILURE TO RE-CALIBRATE THE UNIT WHEN
REQUIRED WILL RESULT IN INCORRECT VALUES
BEING DISPLAYED. THIS WILL RESULT IN INCORRECT
TENSION BEING APPLIED TO A BELT, AND THE BELT
COULD SUBSEQUENTLY FAIL. THE CONSEQUENCE OF
WHICH COULD BE EXTENSIVE ENGINE DAMAGE.
Calibration should only be carried out by a service centre
equipped with the appropriate calibration equipment.
An invalid or failed calibration attempt will result in the
instrument defaulting to ‘failsafe’ mode, where the only
options available to the user are to switch off or re-calibrate
the unit. If the ‘CALIBRATION’ option is inadvertently
selected, the message ‘ARE YOU SURE?’ will be displayed.
Press the ‘Menu’ key to abort the calibration procedure.
If no key is pressed for approximately 30 minutes, the
instrument will switch itself off to save the battery. The unit
can also be switched off at any time by holding down the ‘0’
key until the display disappears.
If the battery needs changing, the red LED will flash and the
display will show the message ‘LOW BATTERY!’
Note: If the battery is completely drained, the instrument
will not operate at all.
The tension gauge requires no maintenance, other than the
unit should be periodically wiped over with a clean cloth.
The keypad is a sealed membrane type, which can easily be
cleaned without damage. Do not clean with solvents.
The Tension Gauge is warranted against defects in material
and workmanship under normal use and service for the period
of one year from the original date of purchase.
Should the instrument become inoperative a repair will be
carried out free of charge to the original purchaser within a
one year period from the original date of purchase.
The warranty shall not apply and will be void if, in the opinion
of the manufacturer, the tension gauge or any of its
components have been damaged or subjected to misuse.
The tension gauge should be calibrated as described in this
manual. The manufacturer reserves the right to refuse any
warranty claim if it is a result of not complying with the
calibration procedures.
Complete and return enclosed registration card.
Calibration procedure
Auto power off
Low battery warning
Maintenance
Warranty procedures

LASER TOOLS Cam Belt Tensioner Gauge 11
Specification
Belt width
Measurement range
Overload warning
Maximum load
Measurement resolution
Measurement accuracy
Display
Audible warning
Key pad
Power source
Battery life
Piezoelectric sounder
5 key tactile membrane keypad
Up to 36mm
0 – 750
0 to 77
0 to 170
0 to 12.0
0 to 53
0 to 14.5
0 to 114
750
850
+/- 10 (or at least 1 sig. digit)
+/- 5% of full scale
16 Characters LCD/3 LEDs
Piezoelectric sound
5 key tactile membrane
4 x 1.5v AA Battery
100 hours approximately
Newtons
Kilograms
Pounds
Ford/Lowener/Vauxhall
BMW
Peiseler/Seat/VAG/Volvo
Seem
Newtons
Newtons
Newtons
Supplied
NOTE:
The tension head is calibrated to this unit.
Calibration can be carried out by D-ZIGN UK LIMITED: 0161 621 5880