Jeep Cherokee 1999 Electronic Service Manual page 1067

9 - 50 2.5L ENGINE
DI SASSEM BLY AN D ASSEM BLY (Cont inue d)
VALVE SPRING TENSION TEST
Use a Un iver sa l Va lve Spr in g Test er a n d a t or qu e
wr en ch t o t est ea ch va lve spr in g for t h e specified t en -
sion va lu e (F ig. 71).
Repla ce va lve spr in gs t h a t a r e n ot wit h in specifica -
t ion s.
Fig. 71 Valve Spring Tester
CYLINDER BLOCK
Rem ove t h e E n gin e Assem bly fr om t h e veh icle.
DISASSEMBL Y
(1) Dr a in t h e en gin e oil. Rem ove a n d disca r d t h e
oil filt er.
(2) Rem ove t h e wa t er pu m p fr om t h e cylin der
block.
(3) Rem ove t h e dist r ibu t or fr om t h e cylin der block.
(4) Rem ove t h e vibr a t ion da m per.
(5) Rem ove t h e t im in g ca se cover a n d la y t h e cover
u pside down .
(6) P osit ion a dr ift pu n ch in t o t h e slot in t h e ba ck
of t h e cover a n d t a p t h e old sea l ou t .
(7) Rem ove t h e t im in g ch a in bu m per.
(8) Rem ove t h e oil slin ger fr om cr a n ksh a ft .
(9) Rem ove t h e ca m sh a ft
r em ove t h e spr ocket s a n d ch a in a s a n a ssem bly.
(10) Rem ove t h e ca m sh a ft .
(11) Rem ove t h e oil pa n a n d ga sket .
(12) Rem ove t h e t im in g ch a in t en sion er.
(13) Rem ove t h e fr on t a n d r ea r oil ga lley plu gs.
(14) Rem ove t h e con n ect in g r ods a n d t h e pist on s.
Rem ove t h e con n ect in g r od a n d pist on a ssem blies
t h r ou gh t h e t op of t h e cylin der bor es.
(15) Rem ove t h e cr a n ksh a ft .
ASSEMBL Y
(1) In st a ll t h e cr a n ksh a ft .
(2) In st a ll t h e con n ect in g r ods a n d t h e pist on s
t h r ou gh t h e t op of t h e cylin der bor es.
(3) In st a ll t h e fr on t a n d r ea r oil ga lley plu gs.
r et a in in g bolt a n d
(4) In st a ll t h e t im in g ch a in t en sion er.
(5) In st a ll t h e ca m sh a ft .
(6) In st a ll t h e spr ocket s a n d ch a in a s a n a ssem bly.
(7) In st a ll t h e oil slin ger t o t h e cr a n ksh a ft .
(8) In st a ll t h e t im in g ch a in bu m per.
(9) In st a ll t h e t im in g ca se cover sea l.
(10) In st a ll t h e t im in g ca se cover.
(11) In st a ll t h e oil pa n ga sket a n d oil pa n .
(12) In st a ll t h e vibr a t ion da m per.
(13) In st a ll t h e wa t er pu m p. Tigh t en t h e m ou n t in g
bolt s t o 31 N·m (270 in . lbs.) t or qu e.
(14) Rem ove t h e dist r ibu t or fr om t h e cylin der
block.
(15) Lu br ica t e t h e oil filt er sea l wit h clea n en gin e
oil. Tigh t en oil filt er t o 18 N·m (13 ft . lbs.) t or qu e.
(16) In st a ll t h e en gin e in t o t h e veh icle.
(17) F ill t h e en gin e wit h clea n lu br ica t ion oil.
(18) F ill t h e coolin g syst em .
CLEAN I N G AN D I N SPECT I ON
ROCKER ARMS AND PUSH RODS
CLEANING
Clea n a ll t h e com pon en t s wit h clea n in g solven t .
Use com pr essed a ir t o blow ou t t h e oil pa ssa ges in
t h e r ocker a r m s a n d pu sh r ods.
INSPECTION
In spect t h e pivot su r fa ce a r ea of ea ch r ocker a r m .
Repla ce a n y t h a t a r e scu ffed, pit t ed, cr a cked or
excessively wor n .
In spect t h e va lve st em t ip con t a ct su r fa ce of ea ch
r ocker a r m a n d r epla ce a n y r ocker a r m t h a t is deeply
pit t ed.
In spect ea ch pu sh r od en d for excessive wea r a n d
r epla ce a s r equ ir ed. If a n y pu sh r od is excessively
wor n beca u se of la ck of oil, r epla ce it a n d in spect t h e
cor r espon din g h ydr a u lic t a ppet for excessive wea r.
In spect t h e pu sh r ods for st r a igh t n ess by r ollin g
t h em on a fla t su r fa ce or by sh in in g a ligh t bet ween
t h e pu sh r od a n d t h e fla t su r fa ce.
A wea r pa t t er n a lon g t h e len gt h of t h e pu sh r od is
n ot n or m a l. In spect t h e en gin e cylin der h ea d for
obst r u ct ion if t h is con dit ion exist s.
ENGINE CYLINDER HEAD
CLEANING
Th or ou gh ly clea n t h e en gin e cylin der h ea d a n d cyl-
in der block m a t in g su r fa ces. Clea n t h e in t a ke a n d
exh a u st m a n ifold a n d en gin e cylin der h ea d m a t in g
su r fa ces. Rem ove a ll ga sket m a t er ia l a n d ca r bon .
Ch eck t o en su r e t h a t n o coola n t or for eign m a t er ia l
h a s fa llen in t o t h e t a ppet bor e a r ea .
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