MCi Crusader II 1989 User manual

MC-9
CRUSADER :0:
--
. ...
\.
MAINTE . NANCE
· MANUAL
0anuary 1 888

THIS DOCUMENT HAS BEEN PROVIDED IN THE ADOBE PDF FORMAT AS A
SERVICE TO THOSE WHO MAY NOT BE ABLE TO LOCATE A HARD COPY OF
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IVl.41NTl:I\IAI\ICE
. 'MANUAL,-·
.. Jantiary 1989
Fl.,IN 3G"-15-176E', · 1-1!!1119, -
PRINTE!) IN U,SA
i ...
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MC-9 MAINtENUJCE
MANUAL
. • • . . . .
~
.. . . - . I
. ,
··Front,_
Axle
._:
_· -Rear.
·Al(1e·
-Bo(.iy...
Brakes &
Ai_r
System
. _ . . .Clutch
'
.
'
.Cooling ·Syst~llJ
•_.•
E·lectrical',_
~System
':
,_
:
-·
·_·.:
··
-·.
En_girie
Fuef·"SysteO,
Lubrication
..
·
'•
steenn9
·
·.
··
.·
.Susj.)ensiora
. .
Trans~jssio"r-1
· -
:Propeller:>
SJ1~'"1
Wheels,-·
-H_ub~f
:J-·•;_Tires·
Heating
·a
Air·
·conditioning
. Lavatory
1
2i
3
4·
s·
6
7-
8
9
10
1~
12
1:3_
14
~
..
15
16
17

Me~9:,M.AI.NTENANCE MANUAL
WELDING CAUTION
Since welding is a procedure which may be carri_ed out either as allowed
(explicitly -or implicitly) by instructions in this manual or carried out by an
independent decision
of the coach owner/operator, the following information
pertaining-to welding
should be read before beginning any welding procedure.
Theprohibitionsand requirementscontainedtherein
must befollowed during the
' Welding:procedure. ·
1. Welding ~~st be done only ,by a qualified and experienced person.
2. Adequateground contacts andbarriers must bepositioned as required to
pro,tect- components (wiring, brake lines, hydraulic lines, etc.) from
damage
due to heat contact by weld splatter arcing or other potentially
damaging events associated with welding.
3. On any coach. turn battery switch to "OFF."
4. Forcoach.es equipped with a battery equalizer. after performing step 3
above:
a. Disconnectthe ground at the equalizer.
b. Disconnect the battery leads.
5. If coach has ATEC or DDEC, remove the ATEC/DDEC power control
fuses.
6. Anyapplicablewelding instructions or prohibitionsgiven bya procedure
must be heeded.
ii

Date
January 1989.
INTRODUCTION
Thismanual contains operation, maintenance andoverhaul information on MC-9 Model Coach.Information in this manual pertains_,,,)
to standard and commonly used optional equipment
Vehicle operation from the driver's standpoint is contained in a separate operator's manual. Detroit Diesel engine information is
found inaseparateservicemanual. Allison transmission infonnationiscontained in the appropriate vendor servicemanual which, like
the engine manual, is supplied separately. .
Allinformation containedin this manualis basedon the latestproductinformation available at time of publication. We reserve the
right
to make publication changes at any time.
HOW TO USE THIS MANUAL
This manual is divided into major sections in the sequence shown on the section index. Ail major sections are divided into
sub-sections
containing descriptions, operation, maintenance, replacement, overhaul and specificatipn information on. related
systems and components. A section
index appears on the first page of each major'section.
PAGE ANO ILLUSTRATION NUMBER
Manual pages and illustrations are numbered consecutively within each major ~ction.
SPECIFICATIONS
Servicedata, torque limits and tolerances are listed at the end of most sections under the headi11g "Specificatioris." !'llanufacturer's
model orpart
numbers areprovided where applicablefor component identification.Detail service partnumbers must be obtainedfrom
the MC-9
Model Parts Manual.
SERVICE INFORMATION BULLETINS
Service Bulletins are issued, when required, to supplement or supersede infonnation in this manual. Information in the bulletins
should be noted and filed for future use.
CUSTOMER SERVICE
Universal Coach Parts of Northlake, IL and Motor Coach Industries, Ltd., Service Parts Division of Canada, know your coach best _j
and are interested in your complete satisfaction. Both offer genuinefactory parts for this MC-9 Model and aii other TMC/MCI Coach
Models. · .
.• .
Servicedepartmentsin both Roswell, N.M.
(U.S. service)and in Winnipeg, Canada{all Canadian service)stand ready to serve you.
Their addresses are:
Transportation Manufacturing Corporation
Service Department
P.O. Box 5670 (R.1.A.C.)
Roswell, N.M. 88202-5670
Motor Coach Industries, Ltd.
Service Parts Division
of Canada
1149 St Matthews Ave.
Winnipeg, Manitoba, Canada R3G0J8
Proper maintenance is important to the safe and reliable operation of the
MC-9 Model coach. The service procedures recommended and described in
this manual are effective methods for performing service operations.
In so.me
instances, the use of special tools is recommended. These tools iiiould be
used when
and as recommended.
Various WARNINGS, CAUTIONS and NOTIC_ES. are contained In this
manual. Theyshouldbe read carefullytom~nimizetherisk of personal injury or
the possibility that improper service methods may be used whic,h could
damage the coach and render it-unsafe. It is important to note that these
cautions and notices are
not all inclusive. We could not evaluate and·advise
users
of all conceivable ways in which service may be done or'ofthe'possible
hazardous consequences of each way. We have not attempted _to· do )his.
Therefore, anyonewho uses aservice procedure or tool not reconimended'by.
the manufacturershouldfirst satisfy himselfthat neitherhissafety riorvehicle
safety
will be jeopardized by the particular method he selects. REFER TO
PAGE ii FOR CAUTIONARY INFORMATION PERTAINING TO WELDING.

Date 1-1-89
MC-9 MAINTENANC.E.,MANLJP.L-
.~.:·•-.-.\(1',-r:::w!"NQ& ..... " it
.FRONT .AXLE
EF:FECTIVE
W:ITH UNIT 41089
STEERING GEAR
FRONT AXLE
PRIOR
TO UNIT 41089
STEERING ARM
Figure 1-1. Front Axle Assemblies.
FRONT AXLE ASSEMBLY
DESCRIPTION
Effectivewith unit41089 the frontaxleassembly is atubu,lar
type of Reversed Elliotdesign. Axle construction consists
of a
tempered seamlesssteel tube with forged steel king pin ends.
On units
prior to 41089, the front axle is a forged steel drop
centerI-beam type.King pin ends are integral parts of the axle
center. See figure 1-1.
Steeringknuckleshavegreasefittingsinbothkingpin bosses
f~r lubrication of the knuckle bushings.The bushingsareof the
sy Steer" type on all models after September 1986. Prior to
·that. the bushings are bronze. Covers and prugs prevent dust
and moisture from entering bushings and serve as seals.
The brakeshoe
spider isdoweledand bolted to the steering
knuckle. Dowel pins are also used to
locate air suspension
mountings.
The
two steering knuckleassemblies are connectedto each
other by a tie rod. Tie rod is threaded at each end and held in
position by clamp bolts. i":iight-hand and left-hand threads are
provided on the tie rod to facilitate toe-in adjustment. Stop
screwsinstalled
at each end ofaxlecenterlimitturningangleof
front wheels.
On the tubular style axles. to detectdevelopment of fatigue
cracks. approximately two quarts of diesel fuel·are installed in
the
hollow tube section. Any axle which leaks should be
replaced.
,mr ■

Date Page
1-2
MC-9 MAINTENANCE MANUAL
Steering knuckles are bushed in the upper and lower pm
bosses
so thatthey mayturn fr:eel¥.about the pins. Bushings are
grooved on the inside to allow grease to flow uniformly to
high-pressure areas. Grease fittings areinstalled at both upper
and lower king pin bosses.
On the earlierMC-9 front axles the tapered steering knuckle
pins are drawn into the axle center by tightening the nut at the
upper end of the pin. Onthe laterMC•9s a straight type knuckle
pin is used. The straighttype pin i~ held in placeby draw keys in
the knuckle. "
Wheel bearings. air suspension. steering and brake parts
which are mounted on thefrontaxlearedescribe<;l in the appli-
cable sections of this manual.
LUBRICATION
Periodic lubrication according to the recommendations in
the
lubrication section of this manual should be carried out.
Points
which require lubrication are the steering knuckle pins.
tie-rod ends and drag link ends. These are provided with
grease fittings for pressure lubrication.
MAINTENANCE
Periodic mspection of the front axle assembly should be
made
to see that all. bolts are tight and that no damage or
distortion has taken place. Suspension support stud nuts.
U-bolt nuts. tie-rod armand steering arm nuts. and stop screws
should be checked and tightened 1f necessary to the torque
specifications shown at the end of this section.Attention should
also be given ·to the condition of the steering knuckle pin and
bushings. If excessive looseness is found• at this point. the
bushings and pins should be replaced.
The
axle manufacturer recommends that the bronze or
"Easy Steer" king pin bushings be replaced when the range of
side-to-side tire movement reaches .030 inch or when the
bushings are worn to amaximumof .010 inch on their diameter.
NOTE: These measurementsaremade with
thewheel bearingstightened on
the spindle.
With new bushings installed. the range of side-to-side tire
movement should not exceed .010 inch maximum. Refer to
Figure 1-2.
Looseness in the steering linkage under normal steering
toads is
sufficient cause to immediately check all pivot pomts
tor wear. regardless of accumulated m!leage. Steering
linkage
p,vot points should be checked each time the axle assembly ,s
lubricated. If any 1nd1cat1on of lateral movement is found. cross
tube ends should be removed for inspection. Looseness at the
steering
linakge pivot points can be visually detected during
movement of the ven1cle steering wheel.
Steering knuckles. king pins. and
bushings may be replaced
without removing the axle from the coach.
.010 INCH MAX.
SIDE-TO-SIDE
TIRE MOVEMENT
FRONT OF TIRE
NEW
BUSHINGS
.030 INCH MAX.
SIDE-TO-SIDE
TIRE MOVEMENT
(OR BUSHING
DIAMETER
WORN .010")
..,&.-·----
FRONT OF TIRE
WORN
BUSHINGS
Figure 1-2. Side-To-Side Tire Movements With New And
With Worn King Pin Bushings.
If extensive overall work or straightening of the front axle
center ,s necessary. the axle should. of course. be removed.
WARNING: Do not attempt to repair,
remove or reinstall front axle with the vehi-
cle supported by jacks only.
FRONT AXLE REMOVAL (Prior to unH 41089)
To remove the entire front axle assembly first block the rear
wheelsto preventthevehiclefrom rolling.Raisethe frontend of
the coach with jacks until the bottom of the coach body is
approximately
18" (45 7.2 mm) from the floor. Block the body in
this position as indicated in Section 3
under Coach Jacking
Points.
CAUTION: Do not raise the body in such a
way that the entire weight of the front axle
will hang on the suspension bellows
assemblies. Damage to the bellows may
result.

Date 1-1-89 Page
1-3
MC-9 MAINTENANCE MANUAL
1. -Remove tires and wheels from axle. See Section 15.
2. Exhaust air pressure from the suspension air tank by
opening the drain
cock at the bottom of the air filter.
3. Disconnect the heightcontrol valve link, and pull down on
height control valve arm to exhaust air from the front inner
beams.
4. Disconnect the hose from the front brake chambers.
5. Disconnect the steering drag link.
6. Disconnect both ends of all radius rods as outlined in this
section
under Radius Rods.
7. Remove nuts from all bolts attaching air springs to the
bracket assel"[lblies.
8. Remove shock absorbersasoutlined in this section under
Shock Absorbers.
9. Lower the axle assembly on jacks until air spring bead
ring bolts are cleared ofthe suspension supports. The axle can
now be carefully removed from
under the vehicle.
Reinstallation
of the axle assembly isthe reverse of removal.
Make sure that air springs mounting pads on axle towers are
-:lean.
FRONT AXLE REMOVAL (Effective with Unit 41089)
To remove the entire front axle assembly first block the rear
wheelsto preventthe
vehicle from rolling. Raise thefrontend of
the
coach with jacks until the bottom of the coach body is
approximately 18" (457.2 mm) from the floor. Block the body in
this position as ir:idicated in Section 3
under Coach Jacking
Points.
CAUTION: Do not raise the body in such a
way that the entire weight of the front axle
will hang
on the suspension bellowsassem-
blies. Damage
to the air springs may result.
1. Remove tires and wheels as detailed in Section 15.
2. Exhaust air pressure from the suspension air tank by
opening drain tank
at bottom of ,he air filter.
3. Disconnect the height control valve link, and pull down on
the
height control valve arm to exhaust air from the front inner
beams.
4. Disconnect the hose from the front brake chambers.
5. Disconnect the steering drag link.
6. Disconnect both ends of all radius rods as outlined in this
section
under Radius Rods.
7. Remove nuts from all bolts attaching a,r spririgs lower
bead rings to the axle tower.
8. Remove shock absorbers as outline-dinthis section under
Shock Absorbers. iit.- ••
9. Lower the axle assembly on Jacks until air spring bead
ring
bolts are cleared of the suspension supports. The axle can
now be carefully removed from under the vehicle.
Reinstallation
of the axle assembly isthe reverse c,f removal.
Make sure that air springs mounting pads on axi•e towers are
clean.
STRAIGHTENING AXLE CENTER -Before Unit 41089
The earlier MC-9 front axle center is a steel forging, heat
treated for strength and
resistance to bending and torsional
strain. If the
center is bent or twisted less than approximately 5
degrees from the original shape, it may be straightened. How-
ever. itis recommended that this work be done only by mechan-
ics who are thoroughly familiar with such operationsand where
the proper facilities are available. Parts whjch are distorted
more than approximately 5 degrees from the original shape
must be replaced, since such distortion exceeds theelastic limit
of the material causing fractures which may result in failure
under ordinary operating conditions.
CAUTION: Do not attempt to straighten
front axles with tubular style axle centers.
Never apply heat
to a front axle forging.
Front axle should be straightened cold
only.
STEERING KNUCKLE
DESCRIPTION
Later MC-9 coaches have front axles w:!h straight knuckle
pins. The earlier MC-9 models have axles with tapered knuckle

Date 1-1-89 Page
1-4
MC-9 MAINTENANCE MANUAL
pins. Figures 1-3 and 1-4 show the steering knuckle construc-
tion
of the two differentaxles.
1. Draw Key -Upper
2. Knuckle Pin
3. Knuckle Bushing • Upper
4. King Pin Cap -Upper
S. Shims
6. Draw Key • Lower
7. Thrust Bearing
8. King Pin Cap • Lower
9. Knuckle Bushing • Lower
10. Knuckle/Spindle
Figure 1-3. Steering Knuckle (Later MC-9)
1. Knuckle Upper Bushing 7. Expansion Plug Lock Ring
2. Knuckle Pin Sleeve ·
8. Expansion Plug
3. Upper Dust Cap 9. Knuckle Lower Bushing
4. Knuckle Pin Nut 10. Tapered Knuckle Pin
5. Shims
11. Knuckle/Spindle
·
6. Thrust Bearing
Figure 1-4. Steering Knuckle {Earlier MC-9).
STEERING KNUCKLE REMOVAL
1. Block the·rear wheels to prev·ent the vehicle from rolling.
Jackupfront
of coach so thattiresclearfloor. Block up securely
at this position and remove jacks. Refer to Section
3. Coach
Jacking Points.
WARNING: Do not attempt
to disassemble
orperform knuckle repairwith vehicle sup-
ported by jacks only.
2. Remove front wheels. hubs and bearings as directed 1n
Section 15.
3. Remove brakechambers and brake shoe hardwarefrom
steering t\!1uckle. Detach brake shoe spider from knuckle and
remove spider. camshaft and slack adjuster as
an assembly.
4. Remove drag link and tie rod from steering arm. Refer to
Steering. Section 11.
5. Remove nuts from steering arms and drive arms out of
steering knuckles.
NOTE:
It is not necessary to remove steer0
ing arms unless service or inspection is
necessary.
6. Upper and lower knuckle pin covers are present on the
newer style axles with straight type knuckle pins. The original
MC-9 axle, withthetapered knucklepin, hasacoveronthe top of
the pin only. Remove the capscrews from the cover(s) and the
gasket(s) beneath the
cov_er. See figure 1 -5. ·
Figure 1-5. Removing Knuckle Pin Cover.
The tapered type knuckle pin has an expansion plug and
lock ring at its tower end. Remove the lock ring with a pair of
snap ring pliers. Dislodge and remove the expansion plug with
a small drift.

Date 1-1-89 ·Page
__:_ __ ,-_
5
__
MC-9 MAINTENANCE MANUAL
7. Thestraightstyleknucklepin is retained in the knuckle by
means of threaded draw keys at the top and bottom of the
knuckle. Remove the draw keys as follows:
a. Loosen locknuton keyand turn it out to the end ofthe
threads. The end of the nut should be flush with the
draw key
end.
b. With a brassdriftand ahammer.firmly striketheend of
the nut to loosen the draw key.
NOTE: Failure to strike the draw key
squarely may result
in a damaged key,
causing removal difficulties.
c. Remove the nut and key from the axle center.
The tapered styleknucklepin is retained intheknuckle by
a nuton thethreaded upperend. Removethe knucklepincotter
pin and
nut Refer to figure 1-6.
Figure 1-6. Removing Nut From Top ofTaperedKnuckle Pin.
8. The knuckle pin. straight or tapered. is removed from the
knuckle by tapping it out using a bronze drift. See figures 1-7
and 1-8.
Figure 1-7. Removal of Straight Style Knuckle Pin.
Figure 1-8. Removal of Tapered Style Knuckle Pin.
The following precautions and procedures will allow the
pins to be removed
with minimum danger of personal injury or
damage to the knuckle pins and bushings.
a. Straight type knuckle pins may be removed through
either
the top or bottom of the.knuckle. Tapered pins can only
be removed through the bottom of the knuckle.
b. Do not strike the knuckle pin directly with a steel
hammer. The pinsare
made of hardened steel. Personal injury
can resultfrom flying
chips and splintersand. inthecase of the
tapered style pin.thethreads
on theupperendwill be damaged.
c. Ifthe bushingsarenotto bereplaced.precautionsmust
betaken
not todamagethem withthe bronzed rift. Grind offany
flaring on the end of the
drift which will contact the pin. Wrap
tape around the drift1/16"
thick forthefirst inch from the end of
the drift. This is especially importantwhen the bushings
are of
the "Easy Steer" type us~d with the straight type.knuckle pin.
9. Ifservicingthestraight pin type knuckle.liftoffthe knuckle
assembly. thrust bearing
and shims. If servicing thetapered pin
style knuckle. remove the
knuckle pin sleeve. and lift off steer-
ing knuckle. thrust bearing. spacing washers. and backplate
assembly. Refer to figure 1-9. ·

Date
1-1-89 Page
---'-_
1
_-s __
MC-9 MAINTENANCE MANUAL
Figure 1-9. Removing Steering Knuckle From Axle.
STEERING KNUCKLE SEALS
Inspectthe grease seals fortears. rips and deterioration. Do
notremove thesealsfrom the steering knuckleunlessreplace-
mentisnecessary
or ifthe knuckleis to berebushed.If seal is to
be removed. pry it out with ascrewdriver. Refer to figure 1-10.
Figure 1-10. Grease Seal Removal.
If seal is being installed in a knuckle which has bronze
bushings:
1. Place steering knuckle bottom side up in a vise equipped
with softmetal protectors. Position
upper knuckle boss(top end
down) between
jaws of vise and lock securely.
NOTE: Seals must be oriented as shown.
Reversal of a seal
will prevent purging of
grease.
2. With the top end ofthe knuckle held firmly in this position.
placethe seal
over theknucklecounterbore. with the rubber lip
facing up. ·
3. Usinga suitablesleeveand a bronzedrift.tap the seal into
the knuckle until it bottomsagainst
the bushing or counterbore.
See figure 1-11.
Figure 1-11. Installation of Grease Seal
(Bronze or "Easy Steer" Bushed Knuckles).
I
~

Date Page
1-7
MC-9 MAINTENANCE MANUAL
4. Repeat this procedure by reversing the knuckle for the
lower seal.
NOTE: In the absence of a suitable driver,
donottap the seal
in with a hammer. Setthe
seal
in the opening and coverit with a rigid
flat metal plate.
Tap the platewith a hammer
directly over the seal until the seal is flush
with themachinedsurface. Do not drivethe
seal any further.
If the seal is installed in a knuckle which has .. Easy Steer"
bushings:
1. Follow instructions 1 and 2 for above bronze bushed
knuckles.
2. Usinga suitable sleeveandabronzedrift. tap the seal into
the knuckle bore until it is flush with the machined surface as
shown
in figure 1-12.
. MACHINED SURFACE
BUSHING
Figure 1-12. GreaH Seal Installed in Knuckle
With "Easy Steer" Bushings.
STEERING KNUCKLE BUSHINGS
The earlier MC-9 front axles have bronze steering knuckle
bushings;thelater
MC-9 frontaxles have Rockwell"EasySteer''
bushings. ·
The tool shown
in figure 1-, 3 should be used when remov-
ing
or replacing the bushings. The tool shown in figure 1-14
should be used to size the bushings.
Figure1-13. Tool- King Pin Bushing Removal &Installation.
These tools may beused with eithertype ·of bushing, but the
diameter
of the cutting surface of the reamer will vary. depend-
ing on whether the reamer is used on bronze or "Easy Steer"
type bushings.
DIMENSIONS:
INCHES
A = 1.774: 0.001
8 =
1.7970: 0.0005 •
8 =1.7955 t .0005 ••
C = 1.7915: 0.001
D = 9.30
MILLIMETERS
A =45.0596 : 0.0254
8 = 45.6438 t 0.0127
C = 45.5041 t 0.0254
D =236.0
• FOR REAMING BRONZE BUSHINGS.
.. FOR REAMING EASY STEER BUSHINGS.
Figure 1-14. Reamer- King Pin Bushing.
Thetoolscan be madefrom round steel barstock.Areaming
tool (part number 20-312) for the "Easy Steer" type bushings
may also be purchased.
di

Date 1-1-89 Page
1-8
MC-9 MAINTENANCE MANUAL
STEERING KNUCKLE BUSHING
REMOVAL AND INSTALLATION
The tool shown in figure 1-13 and a press of at least 5-ton
capacity is required to remove
or install thebronze bushings in
the earlier
MC-9 front axle knuckle, or to remove or install the
"EasySteer"bushingsinthefrontaxleknucklesofthelater MC-9
models.
Beforebeginningthe removal
or installationofthebushings.
fix the steering knuckle firmly on the bed of the press to avoid
knuckle slippage during the bushing removal
or installation.
To remove the bushings. insert the tool's pilot end into the
bore of the bushing and press the bushing from the knuckle.
The procedure for installing the bushings will vary. depend-
ing on
whether the bushing is of the bronze or "Easy Steer"
type. .
To install bronze bushings:
1 Align greaseholes in bushing and in knuckle.The circum-
ferential greasegrooveshould be positionedtoward the end of
the king pin.
2. Firstpressbushing intoknuckleapproximately 1/a". relieve
press pressure and check alignment of tool and bushing.
3. The bushingcannowtiepressedin until itis .135" to .165"
from the insidemachinedsurfaceoftheknuckle.Thisapplies to
both
upper and lowerbushings. Do notinstall seals until after
the reaming operation
is complete. Refer to figure 1-15.
4. Using the ceamer shown in figure 1-14. finish the bush-
ings to 1.7965-to-1 7975 -inchdiameter. The bushings must
also be in line with each other to within
.001 inch. Refer to the
sizing
procedure described later in this section.
1.7965-1.7975 INCH
UPPER AND
LOWER BUSHING
(REAM DIAMETER)
t
Figure 1•15. Bronze Bushing Installation.
.135/.165
To install "Easy Steer" bushings:
1. Press the upper bushing approximately 1 /s" into the
knuckleand relieve the presspressure. Checkalignmentoftool
and bushing.
2. The bushing can now be pressed to the desired depth of
0.477 inch to 0.507 inch from the top of the machined surface.
See figure 1-16.
3. Place the knuckle bottom side up and repeat step 1.
4. Press the lower bushing in to a depth of 0.412 to 0.442
inch from the bottom machined surface. See figure 1-16.
Do
not install the grease seals until the reaming is completed.
5. Using the reamer shown in figure 1-14. finish the bush-
ings to 1.7950-to-1.7960-inch diameter. The bushings must
also be in line with each other to within
.001 inch. Refer to the
sizing procedure described later in this section.
0.4n-0.507 INCH
UPt>ER KNUCKLE BOSS
BUSHING DEPTH
0.412-0.442 INCH
LOWER
KNUCKLE BOSS
BUSHING DEPTH
1.7950-1.7960 INCHES
UPt>ER I
LOWER BUSHING
REAM DIAMETER.
MACHINED SURFACE
KLE
E
SEAL LIP
BUSHING
UPPER I LOWER GREASE SEAL
SEAL INSTALLATION
Figure 1-16. Easy Steer Bushing lnstal'ation
and Grease Seal Installation.

Date .Page
--:---
1
-_
9
__
MC-9 MAINTENANCE MANUAL
.>IZING NEW BUSHINGS
There are several methods of sizing the bushings but the
only method
which will give accuratesize and alignment of the
bore is reaming. Honing and burnishing do not provide good
bushing bore alignment Easy steer bushings are made
of too
resilienta material forthem
to besizedwith aburnishingball or
bar.
The recommended procedure for reaming the bushings is
as follows:
1. Position.the knuckle in a vise with soft metal shims to
protectthe knuckle. It is preferableto havethe king hole verti-
cal.
2. Gently slide the reamer pilotthrough the upper bushing
until the reamer cuttersbegin toengagetheupperbushing. See
figure 1-17.
(Push Down Lightly)
REAM UPPER
BUSHING FIRST
Figure 1-17. Size Upper Bushing.
3. Begin rotating the reamer and applying a lightdownward
pressure with your hand at the same time. Do not force the
reamer by applyingtoo much downwardforce. Thereamer can
be rotated
at any speed but should be done smoothly.
4. Afterthereamer sizes most of the upper bushing, support
the reamer so that it does not drop to the bottom bushing as
it
completes the cut
5. After the upper bushi11g·has been sized. gently slide the
reamerthrough until itengages the bottom bushing. See figure
1-18. Repeat steps 3 and 4 for the bottom bushing.
(Push Down Lightly)
REAM LOWER
BUSHING SECOND
Figure 1-18. Sizing Lower Bushing.
6. Slide the reamer out through the bottom. If the reamer
must be pulled back up through the bushing,
do so only while
rotating the reamer in reverse. Any other way will damage the
bushings.
7. Clear bushing debris from bores before installing seals.
GREASE SEAL INSTALLATION
After the reaming operation iscompleted. install the grease
seals. See the procedure
as described earlier in this section.

Date
1-1-89 Page
1-10
MC-9 MAINTENANCE MANUAL
REASSEMBLY -AXLE CENTER TO STEERING
KNUCKLE
THRUST BEARING INSTALLATION
The earlier
MC-9 frontaxle does nothave a seal atthe thrust
bearing under the steering knuckle. The later MC-9front axles
have a seal atthe thrust bearing.
NOTE: Some of the thrust bearings used in
front axles have the word "TOP" stamped
on the flat face of the bearing retainer. The
stamped word "TOP" should not
be used
for bearing installation purposes. Refer to
the following instructions for proper bear-
ing positioning.
Priortoputting thethrust bearingin theaxle center-knuckle
assembly, if the bearing has a seal, assemble the bearing and
seal by holding the bearing so that the opening between the
bearingcageandtheretainer isup.Thensnaptheseal securely
over the opening. See figure 1-19.
SEAL
Figure 1-19. Bearing And Seal Assembly.
The assembly
of theaxle centerand knucklenow pmceeds
as follows:
1. Position and support the steering knuckle assembly on
the axle center.
2A. Thrust Bearings With Seals -With the seal positioned
ontopofthethrust bearing,slidethebearing and sealassembly
betweenthe I
ower faceofthe axle centerandtheupperface of
the knuckle yoke. See figure 1-20.
NOTE:
The thrust bearing must be seated
on the upper face of the lower knuckle
yoke.
The seal must cover the opening
between the bearing cage
and retainer.
Always install the bearing and seal assem-
bly in the axle with the seal on top. See
figure 1-20.
Figure 1-20. Installing Knuckle And Seal Assembly.
28. Thrust Bearings WithoutSeals -With the open side
of
the thrust bearing facing down. slide the bearing between the
lower face of the axle center and the upper face
of the lower
knuckle yoke. See figure 1-21.
NOTE: The thrust bearing must be seated
on the face of the lower knuckle yoke.
The
bearing should always be installed in the
axle with the closed retainer face up and
the cageface (with the opening} down. See
figure 1-21.
Figure 1-21. Installing Thrust Bearing (No Seal).

Date 1-1-89 ·Page
MC-9 MAINTENANCE MANUAL
3. Shim the knuckle and axle assembly. Shims are positi-
oned between the upper axle center face and the
upper
kn_uckle yoke. See figure 1-22. Shims are used to limit the
vertical movement
of the knucklewith respectto the axle center
and king pin. Someclearancein thisareaisrequired, however,
toallowgreaseto purgefrom the upperbushing area. Carefully
inspectshims,
new or used, to besure noneare kinked, bent or
torn. Discard any thatare damaged. Select a quantity.of shims
to obtainaslittlevertical end playaspossible. Liftthe
knuckle in
position and slidethe shim pack between theaxle center boss
and the knuckle upper yoke.
Figure 1-22. Shimming Axle And Knuckle.
Alignment of the king pin hole in the knuckle and axle
center is
now required for king pin installation. While looking
dowrithrough the king pin hole, shifttheknuckletoalign
it with
the axle center. Now align the shims to be flush with the axle
centeraround theentire circumference
of theking pin hole.The·
shim alignment can only be done through the upper bushing.
Any protrusion of any portion ofthe shim will prevent the king
pin from passing through and result in a damaged shim.
NOTE: Shims are delicate and sharp.
Extremecaution should be exercise~while
aligning shims so as not to cut fingers or
bend the inside diameter of the shims.
Damage to the shims during this entire
procedurerequiresdisassembly and replace-
ment of the damaged parts.
4A To install the straighttype king pin:
a. Smear clear chassisgrease on the bottom half of the
king pin and insertitslowlyintothetop
of theknuckle. King pins
are marked with the Rockwell logo, part numberand the
word
1p" on the top end ofthe pin. Rotate the pin to align the draw
ndY slotswith thedraw key notesintheaxle. Slowlypushthe pin
through the bushing, seal and shim pack. The pin should slide
through the shim pack freely. Any resistance greater than a
handpush inqicates
misalignment Removethepinand realign
the components.Afterthe pin is insertedthroughtheshim pack,
abrasshammermay
be usedto assist in instaHation.Caremust
be taken not to dislodge the
lower grease seal as the king pin
enters the lower knuckle yoke.
b. Center the king pin in the knuckle to equalize the
distance from thetopand bottom surfaces. For knuckleswith a
bottom welsh plug
arrangement increase the bottom gap to
allow for assembly
of the welsh plug and snap ring.
c. lightly tapthedrawkeysintoposition,flatsidetoward
king pin:
do not firmly seat them until after the end play mea-
surement. Install the lowerdraw key from the front side and the
upper drawkeyfrom therear. Assemble sothe wedged ends of
the two keys contactthe king pin and torque to restrictpinfrom
movingwhiletheend play is measured.The p·roceduresforend
play measurementand for seating the
draw keys will be found
later in this section.
NOTE: Never install both draw keys from
the same side.
4B. To install the tapered type king pin:
a. Smear chassis grease on the tapered section of the
pin and insert the pin from the bottom of the knuckle.
b. Smearchassisgreaseon the insideandoutside of the
Ising pinsleeveand insertitintothe upper bushing boreoverthe
king pin.
c. Install king pin nut.and torqueonly enough toseatthe
king pin for end play measurement.
d. Measure end play according to the procedure which
is given later in this section and adjust if necessary.
e. Torque nutto 350-390ft. lbs. (475-529Nm) and install
cotterkey. Ifthe cotter holedoes
not align with thenutcastella-
tion. advance the nut. Do not back the nut off.
5. Measurement of knuckle end play:
NOTE:Aprocedure for measuring endplay
with axleinstalledon coach andwith wheels
and tires installed can be found later in
this
section.
NOTE:
The use of shim gauges (feeler
gauges) for measurement of clearancetoler-
ances
on steering knuckles is not recom-
mended. These will not give an accurate
reading of end play. Use only a dial indica-
tor.
NOTE:End play is the free movement of the
steering
knuckle up and down along the
axis
of the king pin. Some end play is
required
to prevent binding of the knuckle
while turning and to provide a passage for
grease to purge during bushing lubrica-
tion. Excessive end play can cause inter-
ference between the king pin and end caps
or retainers.

Date 1-1-89 Page.
___ 1-_12 __
MC-9 MAINTENANCE MANUAL
a. With king pin caps off. turn the knuckle to the straight
ahead position. Takea rubber mallet and repeatedly strike
the
top draft of the knuckle as shown. This will shift all of the
components
down and remove grease layers so an accurate
reading may
be taken (figure 1-23).
Figure 1-23. Striking Knuckle.
b. Attach the dial indicator with a "C" clamp or magnetic
baseto the
knuckle spindle such thatthe knuckle can be turned
freely as
shown (figure 1-24).
c. Place the dial indicatorplunger on the exposed end of
the king pin so that its line of action is approximately parallel to
the king pin center line (figure 1-24).
d. Zero the dial indicator.
Figure 1-24. Dial Indicator Installation.
e. Measure the knockle clearance (end play) by using a
suitable lever to lifttheknuckle whileobserving the dial
indica-
tor. Make a note of the measurement (figure 1-25).
Figure 1-25. Measuring End Play.
A small hydraulic jack under a
block of wood can be
used beneath the knuckle to provide the necessary lift Keep
lifting the
knuckle until the dial indicator reading levels off
(figure 1-26).
CAUTION: When using a hydraulicjack, be
sure that the axle is supported by two jack
stands. Raising the end in this mannermay
cause an axle supported only in the center
to tip and fall, causing personal injury.
HARO
WOOD BLOCK
Figure 1-26. Lifting Knuckle With Jack.

Date 1-1-89 Page
1-13
MC-9 MAINTENANCE MANUAL
f. Repeatsteps 5a. through 5e. with the knucklein thefull
rightand leftturn positions.This is necessary
to be sure that no
binding orexcessive play is present during turns.
IMPORTANT: If binding exists or zero end
playis measured anywhere in the full travel
of the knuckle, remove shimsas requiredto
obtain end play of .001" to .025".
IMPORT ANT: After measuring knuckle
clearance (end play) of over .025", add
shims between upper knuckle pin boss and
axle center end, as required, to obt.ain an
end play of .001"-.025" (.02-.64 mm)
through full range of tum.
NOTE: Normal seating of the thrust bear-
ing, seal and shims
will increase the end
play reading after a short
time in service.
6. Seating Draw Keys-The knucklepinson later MC-9 units
are retained
by drawkeys. Afterthespecifiedendplayisobtained.
seat the draw keys firmly with a hammerand drift(figure 1-27).
Figure 1-27. Seating Draw Keys.
IMPORTANT: Even though they are
threaded,the keys must be solidly seated in
this manner.Thenut torque on thethreaded
design is only sufficient to hold the key in
position and
is not adequate to properly
seat the key.
Install flanged locknutand torque to 30-40 lb. ft ..
7. Securing Tapered King Pins -On earlier MC-9 coaches
with dropforgedaxlecenters(which havetaperedkingpins),the
procedurefor securing the pin is given in step
4a
"8. Installation of King Pin Caps and Welsh Plugs:
IMPORTANT: Before king pin caps and/or
welsh plugs are installed, recheck draw
keys and king pin nut to be sure the final
staking or torqu-ing procedure has been
completed. Omission of the final king pin
securing steps may result in damaged or
broken king pins and axle centers.
A. On theaxles of later MC-9 coaches:
1) Align king pin caps and gaskets and assemble to
knuckles with capscrews and washers.
2) Gaskets do nothavea top orbottom orientation and
may be installed in either position.
3) Caps do require orienting the flat side toward the
gasketand knuckle. The flat. sealing side contains no number-
ing or lettering.
4) To_rque fasteners to 20-30 lb. ft.
B. On the axles of earlier MC-9 coaches:
1) Place welsh plug into the lower knuckle bore with
the rounded (convex) side toward the king pin.
2) Install lock ring.
9. Bushing Lubrication:
A. Grease upper bushing first. then the lower bushing.
Use molybdenum disulfide grease. If grease does not flow
through the thrust bearing. it
will be necessary to raise the
knuckle with a jack to close off passage of grease around the
thrust bearing. Regrease the lower bushing
and thrust bearing,
then remove jack.
B. Rotate knuckle lock to lock to help distribute the
grease.Notetheknucklewill now be noticeably harder to rotate
than during the end play measurement. This is normal.
C. Repeat step A.
D. On models using draw keys fill the voids in the draw
key holes with grease to prevent corrosion and ease future
disassembly.
10. The steering knuckle/axle center reassembly is now
complete.

Date 1-1-89 Page
1-14
MC-9 MAINTENANCE MANUAL
MEASURING KNUCKLE END PLAY WITH AXLE, WHEELS
AND TIRES INSTALLED
1. Securely block vehicle to prevent rolling.
2. Place a jack under the axle beam as close as possibleto .
the knuckle
end being checkedandjackthevehicle up untilthe
tire is clear of the floor.
3. Attach adial indicator to theaxlebeam witha "C" clamp or
magnetic base (figure 1-28).
Figure 1-28. Dial Gauge Installed.
4. Place the dial indicator plunger on top of the king pm cao
or knuckle forging so that its line of action
is approximately
parallel to the king pin center line.
5. Zero the dial indicator.
6. Measu_re the knuckle clearance (end play) by using a
suitable lever to lifttheknuckle whileobserving the dial indica-
tor. Make a note
of the measurement.
On axles in service. the end play may increase to a maxi-
mum of .065" (1.70
mm) at which time it will be necessary to
re-shim end play back to .001 "- 025" (.02-.64 mm).
NOTE: Both knuckles should be checked.
If a reading of over .065" is taken. remove
th.e lire and king
pm cap and remeasure as per rebuild procedure. If the reading
is still over .065". then re-shim to specifications.
TIE ROD ENDS
The tie-rod assembly is of three-piece .construction com-
prised of a rod and two end assemblies. See figures 1-29 and
1-30. The tie-rod end automatically compensates for wear on
bearingsurfaces. The tie-rod endstudisheldincontactwith the
bearingsurface by tension of aspringwhichholds the seatfirmly
against the inner
end of the stud. An end plug, retained by a
locking ring, holds
the internal tie-rod end parts in position.
Excessiveplayindicatesthatthebearingsurfaces
arewom, and
new tie-rod end assemblies should be installed.
O:i some coaches non-repairable ends are used. These
assemblies must be replaced as a complete unit.
Socket wear is indicated by ball stud turning torque and
socketend movement. End
move_ment may becheckedwith the
socketassembly attached
to its mating arm. Ifa force sufficient
to overcome the sprmg pressure is applied to the end of the
forging. the amount of movement is an indicator of wear. New
socketassemblies should have an end movement of not more
than .020inches(.508 mm). Maximumallowableend movement
on worn sockets is .090 inches {2.28
mm).
To check the turning torque value between the tie rod end
assembly stud and the ball cavity. the socket mustberemoved
from the vehicle. Minimum allowable torque value
1s 5 in. lbs.
(.565 Nm).
Figure 1-29. Tie Rod End (Later MC-9 Coaches).