Generac Power Systems 53187 - Manual (Page 61)

SECTION 2.1
ENGINE SPECIFICATIONS & CHARTS!
L
PART 2
ENGINE MECHANICAL
CYLINDER HEAD:
Com pression Pressure:
Standard Value ................... More than 426.6 psi
Repair Required If ...............Less than 284.4 psI
Check Pressure at................ 200 rpm
Maxim um Cylinder Head Face Distortion:
Standard Value ................... Less than 0.0020 inch
Repair if..............................More than 0.005 inch
Valve Seat (Intake and Exhaust):
Standard Recess................... 0.033 inch
Repair if Greater than.......... 0.070 inch
Valve Seat Standard W idth . 0.047-0.059 inch
Repair W idth if More Than .. 0.079 inch
Valve Seat Angle.................. 45’
Engine Tolerances and Fits
Cylinder Head Tightening Torque:
Torque Value....................... 32.5-36.0 Ft-Lbs
CYLINDER BLOCK:
Type................................... W et, Single Piece
Cylinder Block Bore:
Standard Dim ension............. 2.95 inches
Standard Value .................... 2.9527-2.9535 Inches
Repair if M ore Than............. 2.9606 inches
Allow able Lim its.................. 3.000 inches
Oversize.............................. 0.020, 0.040 inch
Maxim um Distortion of Cylinder Block Upper
Face:
Standard Value ................... 0.0020 inch
Repair if M ore Than.............. 0.005 inch
MAIN REVOLVING SYSTEM:
Piston Skin M axim um Diam eter:
Standard Dim ension............. 2.9527 inches
Standard Value ................... 2.9134 inches
Allow able Lim it.................... 2.9409 inches
Oversize.............................. 0.020, 0.040 inch
Clearance to Cylinder:
Standard Value..................... 0.003-0.004 Inch
Allow able Lim it.................... 0.010 inch
Measure at...........................20" C.
Inside Diam eter of Piston Pin:
Standard Dim ension.............. 0.827 inch
Standard Value..................... 0.8267-0.8269 inch
Piston Pin Hole to Pin Clearance:
Standard Value..................... -0.00008 to +0.0003
Allow able Lim it.................... 0.0008 inch
Piston Pin Outer Diam eter:
Standard Dim ension.............. 0.8268 inch
Standard Value..................... 0.8266-0.8268 inch
Allow able Lim it.................... 0.8260 Inch
Sm all End Bushing to Pin Oil Clearance:
Standard Value..................... 0.0006-0.0012 inch
Allow able Lim it.................... 0.003 inch
Piston Ring Gap:
No. 1 Ring Standard Value .. 0.008-0.014 inch
No. 2 Ring Standard Value .. 0.006-0.012 inch
Oil Ring Standard Value . . . . 0.008-0.014 inch
Allow able Lim it (All Rings) .. 0.039 inch
Piston Ring Groove to Ring Clearance:
No. 1 Ring Standard Value .. 0.002-0.004 Inch
No. 2 Ring Standard Value .. 0.002-0.012 inch
Oil Ring Standard
Clearance............................ 0.002-0.004 inch
Allow able Lim it (No. 1,2) ... 0.001 inch
Allow able Lim it (Oil Ring) ... 0.006 inch
Piston Ring W idth:
No. 1 Ring Std. Dim ension
No. 1 Ring Std. Value_____
No. 2 Ring Std. Dim ension
No. 2 Ring Std. Value . . . .
Oil Ring Std. Dim ension ..
Oil Ring Std. Value............
Oversize Rings Available .
0.079 inch
0.0776-0.0783 inch
0.059 inch
0.0579-0.0587 inch
0.1575 inch
0.1563-0.1571 inch
0.020, 0.040 Inch
Connecting Rod:
Allow able Tw ist Betw een Sm all and large End
Holes (Per 3.94 inches) Not to
Exceed................................ 0.008 inch
Front to Rear Play Betw een Conecting Rod
and Crankpin Allow able
Lim it .................................. 0.028 inch
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