Generac 86640 - Manual (Page 107)

Camshaft Bend (Total Indicated Reading)
Standard...........................Less than 0.008 inch
(0.02mm)
Maximum Tolerance ... 0.004 Inch (0.1mm)
Camshaft End Play.................... 0.0012-0.0122 Inch
(0.03-0.31 mm)
Cam Height
Intake ...............................1.3295-1.3394 inch
(33.77-34.02mm)
Exhaust............................ 1.3280-1.3378 Inch
(33.73-33.98mm)
Wear Limit of
Cam Height.......................0.008 inch (0.2mm)
CYLINDER BLOCK:
Surface Flatness
Standard........................... Less than 0.020 Inch
(0.05mm)
Limit ................................ 0.0039 Inch (0.10mm)
Cylinder Bore Inner Diameter
Standard........................... 2.6772-2.6783 Inch
(68.00-68.03mm)
Wear Limit ....................... 0.0039 Inch (0.10mm)
Cylinder Bore out-of-Round
X-Y................................... Less than 0.0008 inch
(0.02mm)
Cylinder Bore Taper
A-B................................... Less than 0.0008 inch
(0.02mm)
20 10.79)
Main Journal I.D.
Grade No. 0 ..................... 1.9291-1.9293 Inch
(49.000-49.004mm)
Grade No. 1 ..................... 1.9293-1.9294 inch
(49.004-49.008mm)
Grade No. 2 ..................... 1.9294-1.9296 inch
(49.008-49.012mm)
Grade No. 3 .................... 1.9296-1.9298 Inch
(49.012-49.016mm)
PISTON:
Piston Skirt Diameter "A"
Standard............................ 2.6759-2.6770 Inch
(67.967-67.997mm)
"L" Dimension ..........................0.35 inch (9mm)
Piston Pin Hole Diameter ... 0.6694-0.6698 Inch
(17.003-17.012mm)
Piston Clearance to
Cylinder Block.......................... 0.0009-0.0017 inch
(0.023-0.043mm)
PISTON RINGS:
Side Clearance (Standard)
Top................................... 0.0016-0.0029 Inch
(0.040-0.073mm)
Second ............................ 0.0012-0.0025 inch
(0.030-0.063mm)
Oil..................................... 0.0069 Inch (0.175mm)
Side Clearance (All) . . . . 0.008 Inch (0.2mm)
Piston Ring Gap (Standard)
Top (No. 1 Grade)......... 0.0083-0.0118 inch
(0.21-0.30mm)
Top (No. 2 and 3 Grade) 0.0071-0.0118 inch
(0.18-0.30mm)
Second ............................ 0.0059-0.0154 Inch
(0.15-0.39mm)
Oil Ring.............................0.0079-0.0311 inch
(0.20-0.79mm)
Piston Ring Gap Limit (All) .. 0.031 Inch (0.8mm)
PISTON PIN:
Outer Diameter......................... 0.6663-0.6678 inch
(16.924-16.961 mm)
Pin to Piston Clearance _____ 0.0003-0.0005 inch
(0.008-0.012mm)
Interference Fit of Piston
Pin to Connecting Rod .
0.0007-0.0015 Inch
(0.017-0.038mm)
CONNECTING ROD:
Center Distance....................... 4.5079 Inch (114.5mm)
Bend Limit per 3.94 inch (100mm)
Limit..................................0.0020 inch (0.05mm)
Piston Pin Bore Diameter ... 0.6678-0.6684 inch
(16.962-16.978mm)
Big End Play
Standard...........................0.0039-0.0146 inch
(0.10-0.37mm)
Limit..................................0.020 Inch (0.5mm)
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