jost JSK 39 User manual

JSK 36 & JSK 37
EN Installation and operating instructions
JSK 36 & JSK 37
EN Installation and operating instructions
9
39

Table of contents
1 Explanation of symbols......................................... 3
2 Safety information.................................................. 4
2.1 Safety information for operation................................ 4
2.2 Safety information for servicing................................. 4
2.3 Safety information for installation.............................. 5
3 Proper usage........................................................... 6
3.1 Application................................................................. 6
3.2 Unintended use......................................................... 6
3.3 Design........................................................................ 7
4 Operation................................................................. 9
4.1 Fifth wheel coupling closed and locked..................... 9
4.2 Fifth wheel coupling ready for engagement............... 9
4.3 Opening the fifth wheel coupling............................... 10
4.4 Coupling up a semi-trailer......................................... 10
4.5 Uncoupling a semi-trailer........................................... 11
4.6 Checking the locking mechanism.............................. 11
5 Installation............................................................... 12
5.1 General installation instructions................................. 12
5.2 Assembling the fifth wheel coupling on the mounting
plate........................................................................... 13
5.3 Fastening material and tightening torques................ 14
6 Servicing and testing............................................. 15
6.1 Servicing instructions................................................. 15
6.1.1 Fifth wheel coupling with manual lubrication.. 15
6.1.2 Fifth wheel coupling with central lubrication
connection (version Z).................................... 16
6.1.3 Low-maintenance fifth wheel coupling with
top plate liners (version W)............................ 16
6.1.4 Grease specification....................................... 17
6.2 Lubrication instructions.............................................. 18
6.3 Test instructions......................................................... 20
6.4 Wear test................................................................... 20
6.5 Adjusting the locking mechanism.............................. 21
6.6 Wear limit – top plate liners....................................... 22
EN
2MUB 002 004 M01 (REV-C) 04-2019 JSK 36 & JSK 37
JOST IND (REV-A) 06-2019 JSK 39
..............................
6.4.1 Wearing ring, lock jaw ,rubber bush wear limit 21
6.4.2 To remove and install locking mechanism 22
6.4.3 To remove and install pedestal, rubber bush
& swivel pin.......................................................23
6.4.4 Locking mechanism wear limit..........................24
6.5 Adjusting the locking mechanism...................................25
Trailer rubbing plate guideline- JOST
recommendation........

1 Explanation of symbols
WARNING!
Means that death, serious physical injury or significant
material damage can occur if the relevant safety instruc-
tions are not followed.
ATTENTION!
Means that slight physical injury or material damage can
occur if the relevant safety instructions are not followed.
ADVICE!
Contains additional important information.
EN
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2 Safety information
ATTENTION!
The safety instructions are summarised in a single sec-
tion. Where the user of the fifth wheel coupling is in dan-
ger, the safety information is repeated in the various sec-
tions and marked with the danger symbol shown here to
the side.
The relevant safety regulations in your country (for example Health
& Safety at Work) apply for working with fifth wheel couplings, trac-
tor units and semi-trailers. The appropriate safety information in the
operating manual for the tractor unit and the semi-trailer continues
to remain valid and must be followed. The following safety informa-
tion applies to the installation, servicing and mounting work. Items
of safety information directly linked to the activity are listed again
individually.
2.1 Safety information for operation
The fifth wheel coupling may only be operated by authorised
personnel.
Only use the fifth wheel coupling and skid plate on the se-
mi-trailer if they are in perfect technical condition.
The front edge of the skid plate must not be sharp, otherwise it
may damage the fifth wheel coupling or the top plate liners.
Comply with the relevant safety regulations when connecting a
semi-trailer, for example the Health and Safety at Work Regu-
lations. Only couple up a semi-trailer on firm, flat ground.
When coupling up a semi-trailer, the skid plate must be at
the same height as or ideally max. 50 mm lower than the
coupling plate on the fifth wheel coupling. Pressure losses in
the air suspension may change the height of the semi-trailer.
Check the locking mechanism before starting your journey to
ensure that it is properly locked. Only drive the vehicle with the
locking mechanism locked and secured, even when driving
without a semi-trailer (solo driving).
2.2 Safety information for servicing
Only use the specified lubricants for servicing work.
The servicing work should only be conducted by skilled per-
sonnel.
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2 Safety information
2.3 Safety information for installation
The installation area defined by the manufacturer of the tractor
unit may not be changed.
The installation work may only be conducted by authorised
specialists.
Refer to the instructions issued by the vehicle manufacturer,
for example the method of fastening, fifth wheel position, fifth
wheel height, axle load, cavity, mounting plate, slider, etc.
Follow the installation instructions supplied by the mounting
plate and slider manufacturers.
An earth connection must be provided between the fifth wheel
coupling and the vehicle chassis in vehicles that are used for
transporting hazardous substances.
In general, bolt connections are to be tightened to the tightening
torque specified as a setpoint for torque wrenches as per DIN ISO
6789 in classes A or B.
The fifth wheel coupling must be installed on the vehicle in accor-
dance with the requirements of Annex 7 of Regulation ECE R55-01.
It may also be necessary to comply with the licensing regulations of
the appropriate country.
All welding on fifth wheel couplings and their parts is strictly prohib-
ited and will render the type approval void.
EN
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JSK 39
AIS- 091

3 Proper usage
3.1 Application
JOST fifth wheel couplings are mechanical connection devices and
establish the connection between the tractor unit and semi-trailer.
They are designed for mounting on a tractor unit.
Fifth wheel couplings, mounting plates and king pins are connecting
parts that must comply with very high safety requirements and must
also undergo design approval tests. Modifications of any kind will
render both the warranty and the design approval void and therefore
also cancel the vehicle's operating licence.
JOST fifth wheel couplings are specified to comply with Regulation
ECE R55-01 Class 50 and are exclusively to be used in combina-
tion with king pins of Class H50 and Class J steering wedges and
mounting plates or with comparable licensed equipment.
JOST fifth wheel couplings are suitable for use with power steering
systems.
ADVICE!
Technical modifications reserved. The latest information
can be found at www.jost-world.com
3.2 Unintended use
The following will be deemed to be unintended use:
Use of king pins which do not comply with the ISO 337 or DIN
74080 standards
Use of defective king pins. Defects may include, for example,
damage to the king pin, incorrect dimensions and installation
on uneven or damaged skid plates
Use with plastic discs mounted on the semi-trailer
Use with an imposed load or D value above the maximum per-
mitted values
Incorrect towing procedures which adversely affect the smooth
functioning of the fifth wheel coupling
Attachment or fastening of lifting equipment
Other applications which do not comply with the manufactur-
er's recommendations
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AIS-091
JOST fifth wheel couplings are specified to comply with regulation
AIS-091-1 Class G50-X and are exclusively to be used in combination
with king pin Class H50-X and Class J non steering wedges and mou-
nting plates or with comparable licenced equipment.

3 Proper usage
3.3 Design
The fifth wheel coupling is designed in combination with the vehicle
by the vehicle manufacturer (the design must comply with Regula-
tion ECE R55-01, Annex 7).
In addition to the imposed load, the D value is a criterion for the load
capacity of fifth wheel couplings and mounting plates.
It can be calculated using the following formula:
D = Drawbar value [kN]
g = 9.81 m/s2
R = Permissible gross weight of the semi-trailer [t]
T = Permissible gross weight of the tractor unit including U
[t]
U = Maximum imposed load [t]
D =
g x [kN]
0.6 x T x R
T + R - U
Sample calculation:
R = 33 t
T = 17 t
U = 10.5 t
D =
9,81 x = 83,6 kN
0,6 x 17 x 33
17 + 33 - 10,5
Please see the adjacent table for the permitted load data for JOST
fifth wheel couplings. This information is also listed in the relevant
JOST catalogue sheets and stamped on the type plate. This load da-
ta is applicable for proper usage pursuant to regulation ECE R55-01.
EN
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JSK 39
AIS-091-1).
(Just for reference)
AIS-091-01.

3 Proper usage
If they are subject to additional dynamic forces, for example if they
are used on uneven road surfaces or on construction sites, do not
use the complete fifth wheel load and D value, or use a heavier fifth
wheel coupling. Alternatively, consult JOST.
Every fifth wheel coupling has a serial number, which is embossed
on the type plate. This gives the coupling a unique identity.
4
6
5
1
2
3
JSK38/50_15
Example of a type plate
1ECE approval
2Maximum D value in kN
3Maximum imposed load U in t
4Article no.
5Factory number
6Type
Permissible load data
ECE
Test symbol and
approval
number
Type Fifth wheel
coupling
Im-
posed
load U
[t]
D value
[kN]
E
1
55R-01 0116
JSK37C JSK37C,
JSK37CW 20 152
JSK37E,
JSK37EW,
JSK37ER,
JSK37ERW
20 152
JSK37EA,
JSK37EAW 18 135
E
1
55R-01 0294
JSK37E
JSK37ME140,
JSK37ME140W 15 126
E
1
55R-01 1929
JSK37CX JSK37CX 24 170
E
1
55R-01 1927
JSK37CX-1 JSK37CX-1 20 152
E
1
55R-01 0301
JSK36D JSK36D 20 152
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AIS Class
Customer Part number
Type
Production number
AIS approval number7
JSK39DV28 18028
AIS091/16-17/
OC-3327(16-17) JSK39DV1-28
AIS

4 Operation
4.1 Fifth wheel coupling closed and locked
4
1
2
3
5
G50/19
1Handle
2Locking bar
3Lock jaw
4King pin
5Safety catch
4.2 Fifth wheel coupling ready for engagement
G50/18
1
2
3
4
5
1Handle
2Locking bar
3Lock jaw
4King pin
5Safety catch
EN
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12 3
4
latch latch
JSK 39 JOST IND (REV-A) 06-2019
1
2
3
4
JOST IND (REV-A) 06-2019
JSK 39

4 Operation
4.3 Opening the fifth wheel coupling
G50/20
1
Lift the catch (1).
G50/21
A
B
2
Swing the handle (2) towards the
front into position A (to release
the lock).
Pull out the handle (2) as far as
possible into position B.
G50/22
C
2
With the handle (2) pulled out,
swing it forwards into position C
and engage it on the edge of the
plate.
When opening the fifth wheel coupling without a semi-trailer
engaged, the fifth wheel coupling is to be opened as per Fig-
ures G50/20 and G50/21.
The fifth wheel coupling must be ready to engage before cou-
pling up (see section 4.2).
When opening the fifth wheel coupling with a semi-trailer en-
gaged, the fifth wheel coupling is to be opened as per Figures
G50/20, G50/21 and G50/22.
4.4 Coupling up a semi-trailer
Secure the semi-trailer to prevent it rolling away.
The fifth wheel coupling must be ready to engage (see section
4.2). If it is not, open the fifth wheel coupling (see section 4.3).
Check the height of the semi-trailer. The skid plate must ideal-
ly be at the same height as or no more than 50 mm lower than
the fifth wheel coupling plate.
Drive the tractor unit under the semi-trailer.
The locking mechanism will close automatically.
Perform a moving-off test in a low gear.
Check the locking mechanism (see section 4.6).
Connect the supply lines.
Retract the landing gear as described in the operating manual.
Release the parking brake and remove the chocks.
ATTENTION!
Check that the locking mechanism is closed before start-
ing any journey (see section 4.6).
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L

4 Operation
4.5 Uncoupling a semi-trailer
Park the vehicle on flat, firm ground.
Secure the semi-trailer to prevent it rolling away.
Extend the landing gear as described in the operating manual
until the fifth wheel coupling has almost no strain on it.
Disconnect the supply lines.
Open the fifth wheel coupling (see section 4.3).
Drive the tractor unit out from under the semi-trailer.
The fifth wheel coupling is automatically ready for engagement
again (see section 4.2).
4.6 Checking the locking mechanism
G50/23
1
The catch (1) must be down as
shown.
JSK40/15
!
ATTENTION!
The skid plate must rest
on the fifth wheel coupling
without a gap.
G50/31
ADVICE!
To prevent the fifth wheel
coupling being opened
without authorisation, a se-
curity device (for example
a padlock) can be inserted
into the hole of the catch
holder in the handle as
shown.
EN
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latch

5 Installation
5.1 General installation instructions
To fasten the JOST fifth wheel coupling (pursuant to Regulation ECE
R55-01) on the mounting plate or on the auxiliary frame, at least
8 M16 bolts, ideally M16 x 1.5 of strength class 8.8, must be used.
These must be positioned in a symmetrical pattern to the longitudinal
and lateral axes of the fifth wheel coupling.
If the coupling is used in harsh conditions (for example on construc-
tion sites), with trailers with forced steering or with trailers that use
the full D value and/or imposed load, we recommend that you use
all 12 bolts.
Fifth wheel couplings with a design height of over 250 mm and a D
value of over 133 kN must be secured with 12 bolts with strength
class 10.9. This also applies to fifth wheel couplings with a D value
of more than 152 kN or an imposed load of more than 20 t.
We recommend that you use JOST fastening kits (see JOST cata-
logue for order numbers).
The pedestals should make contact with the mounting plate over as
wide an area as possible. With undulating mounting plates, it is nec-
essary to have a support in the middle area as well as the contact in
the screw connection area. We recommend securing the pedestals
in the longitudinal and lateral directions and the mounting plates in
the longitudinal direction using pre-welded thrust plates with zero
play. Use the welding methods set out by the manufacturers of the
vehicle and mounting plate for this purpose (see section 5.2).
There is no need to use thrust plates, however, if it can be ensured
that the correct tightening torque for the bolts and therefore the per-
fect friction contact can be generated and maintained at all times.
The bolt connections are therefore to be designed so that the pre-
scribed tightening torque values or pre-stressing forces can be ap-
plied permanently.
The general rule is that the coating thickness of the paintwork
around the securing area of the bolts must be no more than 120 µm
per component.
The bolt connections are to be secured using state-of-the-art meth-
ods to prevent them coming loose.
Appropriate reinforcement must be made in accordance with the ap-
plication. The fifth wheel coupling must be able to move freely and
must not be in contact with either the mounting plate or parts of the
chassis or auxiliary frame when the vehicle is being driven. If you
use a different installation method (for example chassis installation),
follow the instructions supplied by the vehicle manufacturer.
ATTENTION!
The fifth wheel coupling must be able to move freely and
must not be in contact with any parts of the frame or flitch
when the vehicle is being driven.
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AIS
091 Directive 94/ISO3842ISO
ISO3842
12 10.9
180 28
nos.of M16 bolts,ideally M16*1.5 of strength class 10.9 must be used

5 Installation
5.2 Assembling the fifth wheel coupling on the
mounting plate
1
11
9
3
2
4
5
10
7
9
10
6
8
12
G50/09
1Fifth wheel coupling
2Mounting plate
3Thrust plate to secure the pedestals
4Thrust plate to secure the mounting plate
5Vehicle chassis
6Vehicle auxiliary frame
7Hexagonal bolt DIN EN 28765/28676 (DIN 960/961)
M16 x 1.5-8.8
8Washer 17 DIN7349 6 thick (min. HV295)
9Optional washer (min. HV295) or disc spring
10 Hexagonal nut DIN980 M16 x 1.5-8.8 or M20 x 1.5-8.8
11 Hexagonal bolt DIN EN 28765/28676 (DIN 960/961)
M16 x 1.5-8.8 or M20 x 1.5-8.8
12 Optional washer/disc spring
ADVICE!
Tightening torques must absolutely be adhered to; see
section 5.3
EN
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10.9
10.9 10.9
10.9 10.9
10.9
10.9
11

5 Installation
5.3 Fastening material and tightening torques
Fastening material Strength
class 8.8
Strength
class 10.9
Hexagonal bolt DIN EN 24014/24017 (DIN 931/933) standard thread M16
M20
Hexagonal bolt DIN EN 28765/28676 (DIN 960/961) fine thread M16 x 1.5
M20 x 1.5
Hexagonal bolt DIN 7991 M16 or M16 x 1.5
M20 or M20 x 1.5
210 Nm
410 Nm
225 Nm
460 Nm
170 Nm
330 Nm
260 Nm
500 Nm
280 Nm
500 Nm
250 Nm
400 Nm
ADVICE!
The values shown above are guide values for a coefficient of friction µ tot. = 0.14. Further information is available in VDI 2230.
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6 Servicing and testing
6.1 Servicing instructions
The skid plate on the semi-trailer that engages with the fifth wheel
coupling must meet the following conditions to provide a long service
life and trouble-free function:
Max. 2 mm unevenness
Adequate reinforcement must be assured
Smooth and groove-free surface if possible, without weld
bumps (smooth existing groove burr)
Rounded or chamfered front and side edges
Complete coverage of the fifth wheel coupling support area.
ATTENTION!
Effective lubrication of the top of the fifth wheel coupling
plate (apart from on the W version), the locking mecha-
nism, the pivot bearings (only for the D version) and the
king pin (before using for the first time and after cleaning)
is essential to ensure their long service life. In the W ver-
sion, we recommend applying a thin coat of grease to the
skid plate.
ADVICE!
Before installation, the skid plate must be checked to en-
sure it is even, and the skid plate thickness must also be
checked. The unevenness of the skid plate must be no
more than 2 mm in the load-bearing section of the fifth
wheel coupling. The skid plate must cover the fifth wheel
coupling's set-down surface in every position.
6.1.1 Fifth wheel coupling with manual lubrication
At short intervals, at the latest every 5,000 km:
Uncouple the semi-trailer
Clean the fifth wheel coupling and the skid plate.
Grease the fifth wheel coupling plate, locking mechanism parts
and king pin with high-pressure grease (EP), JOST high-per-
formance lubricant (article no. SKE 013 440 000).
Grease the pivot bearing of version D via the hole on the
top part of the plate (see Figure G50/27) with paste-like high-
pressure grease (EP), JOST high-performance lubricant
(article no. SKE 013 440 000).
G50/27
Grease the pivot bearing of ver-
sion D on both sides (lubrication
adapter SKE 013 440 000).
ADVICE!
The pivot bearings on the C and E versions require no
servicing. The grease nipples on the edge of the fifth
wheel coupling plate are only designed for additional
greasing of the locking mechanism between service in-
tervals.
EN
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6 Servicing and testing
6.1.2 Fifth wheel coupling with central lubrication con-
nection (version Z)
Depending on the conditions in which it is used, the grease spec-
ification and metering, at the latest every 50,000 km or every six
months:
Uncouple the semi-trailer
Clean the fifth wheel coupling and the skid plate.
Check the function of the central lubrication system as de-
scribed in the manufacturer’s instructions.
Lightly grease the fifth wheel coupling plate, locking mecha-
nism parts and king pin with high-pressure grease (EP), JOST
high-performance lubricant (article no. SKE 013 440 000).
Grease the pivot bearing of version D via the holes on the top
part of the plate (see Figure G50/27) with paste-like high-pres-
sure grease (EP), JOST high-performance lubricant (article no.
SKE 013 440 000).
ADVICE!
The pivot bearings on the C and E versions require no
servicing.
6.1.3 Low-maintenance fifth wheel coupling with top
plate liners (version W)
At the latest every 50,000 km or every six months, in harsh condi-
tions every 25,000 km:
Uncouple the semi-trailer
Clean the skid plate and the king pin.
Lightly grease the king pin and the locking mechanism parts
with high-pressure grease (EP), JOST high-performance lubri-
cant (article no. SKE 013 440 000).
Check the top plate liners for signs of wear and damage (see
section 6.6).
ADVICE!
The pivot bearings on the C and E versions require no
servicing.
G50/26
1
In addition, grease the locking
mechanism – with a trailer at-
tached – every 10,000 km using
the grease nipple (1) on the edge
of the fifth wheel coupling plate.
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Trailer rubbing plate guideline- JOST recommendation
Rubbing plate dimension
Length-- 1050mm
Width--- 1050mm
Thickness-12mm (2" king pin)
-14-16mm(3.5" king pin)
Material- ST52-3/Q345D
The skid plate must cover the fifth wheel coupling’s
set-down surface in every position.
Trailer manufacturer must ensure adequate reinforcement
above skid plate.
Rounded or chamfer front and side edges of skid plate.
Maximum 2mm unevenness of skid plate is permissible.
for complete servicing & routine check-up should
be schedule in every 10,000 km.
60,000
30,000

6 Servicing and testing
You can also install automatic lubricant dispensers. To prevent cor-
rosion on the skid plate, we recommend that the skid plate is
greased lightly during the above service intervals.
ADVICE!
When you clean the fifth wheel coupling, you may pro-
duce waste products that contain polluting substances.
We would like to point out that you must comply with the
various national waste regulations for the disposal of this
waste.
6.1.4 Grease specification
We recommend high-pressure grease (EP), e.g. JOST high-perfor-
mance lubricant (article no. SKE 013 440 000).
EN
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6 Servicing and testing
6.2 Lubrication instructions
KSK37/051
2
1 1
3
4
5
6
1Handle 2Fifth wheel coupling plate 3Lock jaw
4Locking bar 5Hinge joints and lever guide 6Wearing ring
Lubricate areas marked in yellow:
Side of handle (1), hinge joints and lever guides (5).
Generously lubricate the top side (2) and completely fill the lubricating groove (except W version – the top plate liners do not have to
be greased; JOST top plate liners are resistant to lubricating greases).
Lubricate lock jaw (3) and locking bar (4) with the fifth wheel coupling closed.
With the standard version (not the low-maintenance version), the centre area around the wearing ring (6) must be completely filled
with grease (see marked area).
Grease specification: We recommend JOST high-performance lubricant (article no. SKE 013 440 000).
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(Ideal Fifth Wheel Coupler Picture)
1
24
3
45
6
(5). .

6 Servicing and testing
ATTENTION!
A second person is needed to close the lock.
A tool such as a large slotted screwdriver can be used to
swivel the lock jaw (1). The lock jaw (1) must never be
swivelled by hand. There is a risk of crushing.
2
1
G50/040
Have a second person pull
handle (2) until the lock jaw
(1) is free.
Hold handle (2) in this posi-
tion.
3
1
G50/041
Swivel lock jaw (1) forward,
e.g. with a large slotted
screwdriver, until the locking
bar (3) is free.
3
2
1
G50/042
Slowly move handle (2) into
closed position.
Grease all sides of lock jaw
(1) and locking bar (3).
ATTENTION!
Open the fifth wheel coupling before it is next coupled up
(see section 4.3).
EN
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1
2
1
2
3
1
3

6 Servicing and testing
6.3 Test instructions
Depending on the conditions of use, but no later than every 50,000
km or every six months, the fifth wheel coupling, the mounting plate,
the slider and the king pins should be checked for:
Function
Wear
Correct position of the fastening elements (check prescribed
torque values)
Damage or distortion
Cracks
Corrosion
To ensure adequate lubrication
To ensure the smooth running of the mechanisms
and repaired where necessary (see the appropriate JOST repair in-
structions at www.jost-world.com).
6.4 Wear test
Fifth wheel couplings and king pins are subject to more or less wear
depending on the conditions in which they are used, and this wear
is noticeable by play towards the front of the vehicle. Excessive play
causes shocks and may lead to instability on the road and damage to
the fifth wheel coupling, mounting plate, sliders and vehicle chassis.
JOST fifth wheel couplings have a manual infinite adjustment facility
for the locking mechanism to extend their service lives.
ATTENTION!
The wear on the king pin must not be compensated for
through adjustment.
71
-73 mm
84-82.5 mm
49
-50.8 mm
JSK40/05
When the wear limit on the king pin has been reached, it must be
replaced. After the king pin has been replaced, the locking mecha-
nism must be adjusted again.
Play caused by wear on the king pin should either be accepted if
within the permitted wear limit for the king pin (see Figure JSK 40/05)
or should be rectified by fitting a new king pin.
ADVICE!
After work on the locking mechanism or after replace-
ment of the lock jaw, wearing ring or locking bar, the lock-
ing mechanism must always be readjusted in order to en-
sure the base clearance of 0.3 mm.
20 MUB 002 004 M01 (REV-C) 04-2019 JSK 36 & JSK 37
JOST IND (REV-A) 06-2019 JSK 39
& tear(wearing ring, lock jaw, locking bar & rubber bush,etc.)