Ariel JGI, Technical Manual

Page: 24 / 178

F
OR
M
ODELS
: JGI, JGM, JGN, JGP
AND
JGQ S
ECTION
1 - D
ESIGN
S
PECIFICATIONS
& D
ATA
PAGE 1-14 9/08
T
ABLE
1-9 P
ISTON TO
B
ORE
C
LEARANCE AND
C
ONVENTIONAL
P
ISTON
R
ING
E
ND
G
AP
, I
N
. (mm) - JG & SG C
LASS
C
YLINDERS
BORE
DIAMETER
a
PISTON TO BORE
CLEARANCE
PISTON RING END GAP -
NON-METALLIC
New Maximum
1.25 (32)
b 0.025 to 0.033 (0.64 to 0.84) 0.018 to 0.028 (0.46 to 0.71) 0.112 (2.85)
1.5 (38)
2 0.030 to 0.038 (0.76 to 0.97) 0.021 to 0.031 (0.51 to 0.79) 0.124 (3.15)
1.625 (41)
2 0.030 to 0.038 (0.76 to 0.97) 0.023 to 0.033 (0.58 to 0.84) 0.132 (3.35)
1.75 (44)
2
0.030 to 0.038 (0.76 to 0.97) 0.025 to 0.035 (0.64 to 0.89) 0.140 (3.55)
2.75 (70) 0.009 to 0.014 (0.23 to 0.36) 0.027 to 0.033 (0.69 to 0.81) 0.132 (3.35)
3 (76) 0.009 to 0.014 (0.23 to 0.36) 0.030 to 0.036 (0.76 to 0.91) 0.144 (3.66)
3.375 (86) 0.010 to 0.015 (0.25 to 0.38) 0.034 to 0.041 (0.88 to 1.04) 0.164 (4.17)
3.625 (92) 0.010 to 0.015 (0.25 to 0.38) 0.036 to 0.044 (0.91 to 1.12) 0.176 (4.47)
3.875 (98) 0.011 to 0.016 (0.28 to 0.41) 0.039 to 0.047 (0.99 to 1.19) 0.188 (4.78)
4.125 (105) 0.011 to 0.016 (0.28 to 0.41) 0.041 to 0.050 (1.04 to 1.27) 0.200 (5.08)
4.75 (121) 0.012 to 0.018 (0.30 to 0.46) 0.057 to 0.077 (1.45 to 1.96) 0.308 (7.82)
5.125 (130) 0.012 to 0.018 (0.30 to 0.46) 0.061 to 0.081 (1.55 to 2.06) 0.324 (8.23)
6.125 (156) 0.013 to 0.019 (0.33 to 0.48) 0.073 to 0.093 (1.85 to 2.36) 0.372 (9.45)
6.5 (165) 0.014 to 0.020 (0.36 to 0.51) 0.077 to 0.097 (1.96 to 2.46) 0.388 (9.86)
7.125 (181) 0.015 to 0.021 (0.38 to 0.53) 0.085 to 0.105 (2.16 to 2.67) 0.409 (10.39)
7.5 (191) 0.015 to 0.021 (0.38 to 0.53) 0.089 to 0.109 (2.26 to 2.77) 0.430 (10.92)
8.5 (216) 0.017 to 0.023 (0.43 to 0.58) 0.102 to 0.122 (2.59 to 3.10) 0.488 (12.40)
8.875 (225) 0.018 to 0.024 (0.46 to 0.61) 0.106 to 0.126 (2.69 to 3.20) 0.504 (12.80)
a. Conventional piston rings are standard for JG Class Cylinders, except 2-1/2JG-FS-HE Class cylin-
ders with bore diameters of 2.25” (57mm) & 2.5” (64); 3JG-CE, 2.75” (70) & 3” (76); and 3-5/8JG-
CE, 3.375” (86) & 3.625” (92), which use piston/rider rings. Piston/rider rings are optional for other
JG Cylinders, except for 1-3/4JG-FS-HE which uses conventional rings and wear band.
b. These sizes use conventional piston rings and wear band, see Table 1-10 for wear band values.
T
ABLE
1-10 W
EAR
B
AND
E
ND
G
AP
& R
ADIAL
P
ROJECTION
(
NEW
) -
1-3/4JG-FS-HE & 1-3/4SG-FS-HE C
LASS
,
I
N
. (mm)
BORE
DIAMETER
END GAP
MINIMUM
RADIAL PROJECTION SIDE CLEARANCE
1.25 (32) 0.049 (1.24) 0.005 to 0.012 (0.13 to 0.30) 0.010 to 0.014 (0.25 to 0.36)
1.5 (38) 0.049 (1.24) 0.0075 to 0.0145 (0.19 to 0.37) 0.010 to 0.014 (0.25 to 0.36)
1.625 (41) 0.052 (1.32) 0.0075 to 0.0145 (0.19 to 0.37) 0.010 to 0.014 (0.25 to 0.36)
1.75 (44) 0.058 (1.47) 0.0075 to 0.0145 (0.19 to 0.37) 0.010 to 0.014 (0.25 to 0.36)