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Cub Cadet 1250 Engine

Cub Cadet 1250 Engine Specifications

Engine Model - K301AQS
Engine Type - Gasoline 4-Cycle, single cylinder air-cooled
Number of Cylinders - 1
Displacement, L (cu in) - 0.476 (29.1)
Engine Bore, mm (in) - 85.6 (3.37)
Engine Stroke, mm (in) - 82.6 (3.25)
Maximum Horse Power, hp (kW) - 12.0 (9.0)
Rated Engine Speed, rpm - 3600
Fuel System - Carburetor
Carburetor Model - Kohler/Walbro
Carburetor Type - Fixed main jet or adjustable main jet
Lubrication System - Splash type
Cooling System - Forced-air
Ignition System - Magneto or battery
Starter Type - Recoil or electric

Cub Cadet 1250 Engine Maintenance Data

Engine Oil and Filter

Engine Oil Type (Summer) - SAE 30W
Engine Oil Type (Winter) - SAE 5W-20, 5W-30
Oil Classification - API SF, SG
Oil Capacity, L (qts) - 2.0 (2.1)
Oil Filter Part Number - 52-05025
Air Filter Part Number - 235116S

Carburetor Adjustment

Kohler Adjustable Jet (Low Idle) - 2-1/2 turns
Kohler Adjustable Jet (High Idle) - 2 turns
Walbro Fixed Jet (Low Idle) - 1-1/4 turns
Walbro Adjustable Jet (Low Idle) - 1-3/4 turns
Walbro Adjustable Jet (High Idle) - 1-1/8 turns

Valve Adjustment

Intake Valve Clearance - 0.20-0.25 mm (0.008-0.010 in.)
Exhaust Valve Clearance - 0.40-0.50 mm (0.017-0.019 in.)
Intake Valve Guide Depth - 40.126 mm (1.586 in.)
Exhaust Valve Guide Depth - 37.874 mm (1.497 in.)

Ignition System

Spark Plug Type - Champion RH10
Spark Plug Size, mm (in) - 14.0 (0.553)
Spark Plug Gap, mm (in) - 0.65 (0.0256)
Breaker Point Gap (Nominal), mm (in) - 0.50 (0.020)

Cub Cadet 1250 Engine Service Specifications

Cylinder Block

Sleeve Internal Diameter, mm (in) - 85.7123-85.7377 (3.3745-3.3755)
Piston Skirt Outside Diameter, mm (in) - 85.4710-85.5472 (3.365-3.368)
Top Compression Ring End Gap, mm (in) - 0.177-0.432 (0.007-0.017)
Second Compression Ring End Gap, mm (in) - 0.177-0.432 (0.007-0.017)
Connecting Rod Small End Inside Diameter, mm (in) - 22.2428-22.2504 (0.8757-0.876)
Piston Pin Outside Diameter, mm (in) - 22.2300-22.2352 (0.8752-0.8754)

Valves

Valve Clearance (Intake), mm (in) - 0.20-0.25 (0.0079-0.0099)
Valve Clearance (Exhaust), mm (in) - 0.43-0.48 (0.0169-0.0189)
Intake Valve Head Diameter, mm (in) - 34.798-35.052 (1.370-1.380)
Exhaust Valve Head Diameter, mm (in) - 28.448-28.702 (1.120-1.130)
Valve Stem Outside Diameter (Intake, Std), mm (in) - 7.887-7.899 (0.3105-0.3110)
Valve Stem Outside Diameter (Exhaust, Std), mm (in) - 7.833-7.851 (0.3084-0.3091)
Valve Guide Inside Diameter (Intake, Exhaust), mm (in) - 7.894-7.919 (0.312-0.313)
Valve Seat Angle (Intake, Exhaust), degrees - 89
Valve Seat Width (Intake), mm (in) - 0.936-1.139 (0.037-0.045)
Valve Seat Width (Exhaust), mm (in) - 0.936-1.139 (0.037-0.045)
Valve Guide Depth (Intake), mm (in) - 40.126 (1.586)
Valve Guide Depth (Exhaust), mm (in) - 37.874 (1.497)
Valve Face Angle (Intake, Exhaust), degrees - 45

Cub Cadet 1250 Engine Tightening Torque Specs

Cylinder Head Bolts, Nm (ft-lbs) - 34-41 (25-30)
Flywheel, Nm (ft-lbs) - 68-81 (50-60)
Spark Plug, Nm (ft-lbs) - 25-30 (18-22)
Connecting Rod, Nm (ft-lbs) - 32.1 (23.8)
Governor Bushing, Nm (ft-lbs) - 11.2-13.6 (8.3-10.1)
Fuel Pump Mounting Screws, Nm (ft-lbs) - 4.2-5.1 (3.1-3.8)

CUB CADET TRACTORS TROUBLESHOOTING
1050	1863	2166	2182	2186
3184	3205	GT1554	GT2550	GTX2100
LT1040	LT1042	LT1045	LT1046	LT1050
LT2180	LTX1040	LTX1042	LTX1045	LTX1046
LTX1050	SLTX1054	XT1 LT42	XT1 LT46	XT3 GSX