Jeep Cherokee 1999 Electronic Service Manual page 1069

9 - 52 2.5L ENGINE
CLEAN I N G AN D I N SPECT I ON (Cont inue d)
(3) Mea su r e t h e cylin der bor e dia m et er cr osswise
t o t h e cylin der block n ea r t h e t op of t h e bor e. Repea t
t h e m ea su r em en t n ea r t h e m iddle of t h e bor e, t h en
r epea t t h e m ea su r em en t n ea r t h e bot t om of t h e bor e.
(4) Det er m in e t a per by su bt r a ct in g t h e sm a ller
dia m et er fr om t h e la r ger dia m et er.
(5) Rot a t e m ea su r in g device 90° a n d r epea t st eps
a bove.
(6) Det er m in e ou t -of-r ou n dn ess by com pa r in g t h e
differ en ce bet ween ea ch m ea su r em en t .
(7) If cylin der bor e t a per does n ot exceed 0.025
m m (0.001 in ch ) a n d ou t -of-r ou n dn ess does n ot
exceed 0.025 m m (0.001 in ch ), t h e cylin der bor e ca n
be h on ed. If t h e cylin der bor e t a per or ou t - of-r ou n d
con dit ion exceeds t h ese m a xim u m lim it s, t h e cylin der
m u st be bor ed a n d t h en h on ed t o a ccept a n over size
pist on . A sligh t a m ou n t of t a per a lwa ys exist s in t h e
cylin der bor e a ft er t h e en gin e h a s been in u se for a
per iod of t im e.
HONING—CYLINDER BORE
Th e h on in g oper a t ion sh ou ld be closely coor din a t ed
wit h t h e fit t in g of pist on s a n d r in gs. Th is will en su r e
specified clea r a n ces a r e m a in t a in ed.
SPECI FI CAT I ON S
2.5L ENGINE SPECIFICA TIONS
En g in e D e s c rip tio n
E n gin e Type . . . . . . . . . . . . . . . . . In -lin e 4 Cylin der
Bor e a n d St r oke . . . 98.4 x 81.0m m (3.88 x 3.19 in .)
Displa cem en t . . . . . . . . . . . . . . . . . 2.5L (150 cu . in .)
Com pr ession Ra t io . . . . . . . . . . . . . . . . . . . . . . 9.1:1
F ir in g Or der . . . . . . . . . . . . . . . . . . . . . . . . 1–3–4–2
Lu br ica t ion . . . . P r essu r e F eed–F u ll F low F ilt r a t ion
Coolin g Syst em . . Liqu id Cooled–F or ced Cir cu la t ion
Cylin der Block . . . . . . . . . . . . . . . . . . . . . Ca st Ir on
Cr a n ksh a ft . . . . . . . . . . . . . . . . . Ca st Nodu la r Ir on
Cylin der H ea d . . . . . . . . . . . . . . . . . . . . . . Ca st Ir on
Ca m sh a ft . . . . . . . . . . . . . . . . . . . . . . . . . Ca st Ir on
P ist on s . . . . . . . . . . . . . . . . . . . . . . Alu m in u m Alloy
Cylin der Com bu st ion Ca vit y . . . . . . Dou ble Qu en ch
Con n ect in g Rods . . . . . . . . . . . . Ca st Ma llea ble Ir on
Ca m s h a ft
H ydr a u lic Ta ppet Clea r a n ce . . . . . . . . . Zer o La sh
Bea r in g Clea r a n ce . . . . . . . . . . 0.025 t o 0.076 m m
B e a rin g J o u rn a l D ia m e te r
No. 1 . . . . . 51.54 t o 51.56 m m (2.029 t o 2.030 in .)
No. 2 . . . . . 51.28 t o 51.31 m m (2.019 t o 2.020 in .)
No. 3 . . . . . 51.03 t o 51.05 m m (2.009 t o 2.010 in .)
No. 4 . . . . . 50.78 t o 50.80 m m (1.999 t o 2.000 in .)
(0.001 t o 0.003 in .)
Ba se Cir cle Ru n ou t . . . . . . . . . . . 0.03 m m - m a x.
Ca m s h a ft Lo be Lift
E xh a u st . . . . . . . . . . . . . . . . 6.579 m m (0.259 in .)
In t a ke . . . . . . . . . . . . . . . . . 6.477 m m (0.255 in .)
Va lv e Lift
E xh a u st . . . . . . . . . . . . . . 10.528 m m (0.4145 in .)
In t a ke . . . . . . . . . . . . . . . . 10.350 m m (0.4075 in .)
In ta k e Va lv e Tim in g
Open s . . . . . . . . . . . . . . . . . . . . . . . . 15.4° BTDC
Closes . . . . . . . . . . . . . . . . . . . . . . . . . . 58° ABDC
Ex h a u s t Va lv e Tim in g
Open s . . . . . . . . . . . . . . . . . . . . . . . . . 52.8 BBDC
Closes . . . . . . . . . . . . . . . . . . . . . . . . . 26.2° ATDC
Va lve Over la p . . . . . . . . . . . . . . . . . . . . . . . . 41.6°
In t a ke Du r a t ion . . . . . . . . . . . . . . . . . . . . . 253.3°
E xh a u st Du r a t ion . . . . . . . . . . . . . . . . . . . . . 259°
Cra n k s h a ft
E n d P la y . . . . . . . . . . . . . . . . . 0.038 t o 0.165 m m
Ma in Bea r in g J ou r n a l
Dia m et er . . . . . . . . . . . . . . . 63.489 t o 63.502 m m
Ma in Bea r in g J ou r n a l Widt h
No. 1 . . . . . 27.58 t o 27.89 m m (1.086 t o 1.098 in .)
Ma in Bea r in g J ou r n a l Widt h
No. 2 . . . . . 32.28 t o 32.33 m m (1.271 t o 1.273 in .)
Ma in Bea r in g J ou r n a l Widt h
No. 3-4-5 . . 30.02 t o 30.18 m m (1.182 t o 1.188 in .)
Ma in Bea r in g Clea r a n ce . . . . . . . 0.03 t o 0.06 m m
Ma in Bea r in g Clea r a n ce (P r efer r ed) . . . 0.051 m m
Con n ect in g Rod J ou r n a l
Dia m et er . . . . . . . . . . . . . . . . . 53.17 t o 53.23 m m
Con n ect in g Rod J ou r n a l
Widt h . . . . 27.18 t o 27.33 m m (1.070 t o 1.076 in .)
Ou t -of-Rou n d (Ma x. All J ou r n a ls) . . . . . 0.013 m m
Ta per (Ma x. – All J ou r n a ls) . . . . . . . . . 0.013 m m
Cy lin d e r B lo c k
Deck H eigh t . . . . . . . . . . . . 236.73 m m (9.320 in .)
Deck Clea r a n ce . . . . . . . . . . 0.000 m m (0.000 in .)
Cylin der Bor e Dia m et er —
St a n da r d . . . . . . . . . . . . . . . . . 98.45 t o 98.48 m m
Cylin der Bor e Dia m et er —
Ta per (Ma x.) . . . . . . . . . . . . 0.025 m m (0.001 in .)
Cylin der Bor e Dia m et er —
Ou t -of-Rou n d (Ma x.) . . . . . . 0.025 m m (0.001 in .)
Ta ppet Bor e Dia m et er . . . . . 23.000 t o 23.025 m m
X J
(0.001 in . - m a x.)
(0.0015 t o 0.0065 in .)
(2.4996 t o 2.5001 in .)
(0.001 t o 0.0025 in .)
(0.002 in .)
(2.0934 t o 2.0955 in .)
(0.0005 in .)
(0.0005 in .)
(3.8759 t o 3.8775 in .)
(0.9055 t o 0.9065 in .)