PART V - COMPLETE OVERHAUL

Section 8 TABLE OF FITS - AERONCA ENGINES 

TOLERANCES 

Replace	Minimum	Desired	Maximum	or Refit BALL & ROLLER BEARINGS: 

Thrust Bearing on Crankshaft	.003L	.0010L	.0015L	.0020L 

Thrust Bearing in Crankcase	.0019T	.0009T	.0003T	.0010L 

Main Bearing on Crankshaft	.0008T	.0002T	.0002L	.0008L 

Main Bearing in Crankcase-Backplate	.0020T	.0010T	.0005T	.0010L 

Camshaft Ball Bearings on Camshaft	.0010T	.0001L	.0002L	.0010L 

Camshaft Ball Bearings in Crankcase	.0018T	.0010T	.0005T	.0010L 

Camshaft Ball Bearing in Sleeve	.0006T	.0002L	.0007L	.0012L 

Rocker Arm Bearing on Shaft	.0001T	.0005L	.0010L	.0015L 

Rocker Arm Bearing in Rocker Arm	.0005T	.0000	.0005L	.0010L 

CONNECTING ROD BEARINGS: 

No. 358 Crankshaft & Con Rod Assembly 

Total Radial Clearance - Dia, (1/2" Rollers with Cage)	.0005L	.0008L	.0010L	.0018L 

No. 718-Crankshaft & Con Rod Assembly Total Radial Clearance - Dia. (Needle Rollers)	
.0005L	.0008L	.0010L	.0025L 

No. 750-Crankshaft & Con Rod Assembly Total Radial Clearance - Dia, (Plain Bearings)	.0005L	
.0008L	.018L	.0025L 

CAM FOLLOWER ASSEMBLY: 

Tappet In Guide	.0005L	.0008L	.0011L	.0040L 

Guide in Crankcase	.0005T	.0000	.0010L	.0020L 

Roller on Pin	.0005L	.0010L	.0020L	.0040L 

Roller in Tappet-Side	.0020L	.0030L	.0050L	.0100L 

Pin in Tappet	.0015T	.0010T	.0000	.0010L 

CAMSHAFT SLEEVE IN CRANKCASE	.0010T	.0000	.0010L	.0015L 

CRANKSHAFT ASS'Y-END FLOAT	.0010	.0030L	.0080L	.0100L 

GEARS 

Crankshaft-Camshaft Gear Train - (Backlash)	.0030L	.0050L	.0080L	.0140L 

Magneto Drive Gear on Spindle	.0010L	.0010L	.0025L	.0035L 

Camshaft Gear & Backplate-Side	.0200L	.0320L	-	- 

OIL PUMP ASSEMBLY: 

Drive Shaft in Pump Body	.0010L	.0020L	.0030L	.0040L 

Gears on Idler Shaft	.0005L	.0010L	.0025L	.0040L 

Gears in Pump - Side	.0010L	.0015L	.0030L	.0060L 

OIL INLET TO CRANKSHAFT: 

Oil Spindle in Bushing	.0020L	.0025L	.0040L	.0070L 

Bushing in Crankshaft Gear	.0025T	.0015T	.0005T	.0000L 

PISTON: (No. 733 4 1/4" Dia) 

Piston in Cylinder-top Diameter	.0260L	.0280L	.0300L	.0350L 

Piston in Cylinder-skirt Diameter	.0135L	.0150L	.0165L	.0215L 

PISTON: (No. 179 4 1/8" Dia) 

Piston in Cylinder-top Diameter	.0310L	.0330L	.0350L	.0400L 

Piston in Cylinder-skirt Diameter	.0185L	.0200L	.0215L	.0265L 

PISTON PIN: 

Piston Pin in Piston	.0004T	.0002T	.0005L	.0015L 

Piston Pin in Con Rod Bushing	.0008L	.0012L	.0015L	.0025L 

PISTON PIN BUSHING: 

Bushing in Con Rod	.0030T	.0025T	.0010T	.0000L 

PISTON RINGS: 

Compression Ring in Piston-Side	.0020L	.0025L	.0035L	.0060L 

Oil Regulating Ring in Piston-Side	.0020L	.0025L	.0035L	.0060L 

All Rings - Gap	.0120L	.0120L	.0160L	.0300L 

PROPELLER HUB: 

Hub on Crankshaft Taper: 

AT FRONT END OF HUB-DIA.	.0000L	.0001L	.0005L	- 

AT REAR END OF HUB-DIA.	TIGHT FIT--------------------------- 

Hub in Wood Propeller-Dia.	SNUG PUSH FIT-------------------- 

Bolts thru Wood Propeller - Dia.	SNUG DRIVE FIT------------------ 

Clearance Between Propeller Hub Bolts and Front Cover Bolts-end	.0800L	
MINIMUM------------- 

ROCKER ARM ASSEMBLY: 

Bearing in Rocker Arm - Dia.	.0005T	.0000	.0005L	.0010L 

Shaft in Bearing - Dia.	.0001T	.0005L	.0008L	.0015L 

Shaft in Cyl Head Bushing - Dia.	.004L	.0006L	.0010L	.0020L 

Rocker Arm Roller on Pin - Dia.	.0002L	.0004L	.0008L	.0040L 

Rocker Arm Roller in Arm - Side	.0020L	.0050L	.0090L	.0120L 

Shaft Bushing in Cyl Head - Dia.	.0020T	.0030T	.0040T	.0000L 

VALVES AND GUIDES: 

Intake Valve in Guide	.0020L	.0025L	.0035L	.0060L 

Exhaust Valve in Guide	.0020L	.0025L	.0035L	.0080L 

Guide in Cylinder Head	.0015T	.0020T	.0030T	.0000L 

TACHOMETER DRIVE: 

Drive Shaft in Bushing - Dia.	.0015L	.0020L	.0045L	.0065L 

Bushing & Shaft-end Clearance (*) One qtr. Turn of bushing loose)	.0030L	.0030*L	.0045L	
.0065L