Tecumseh HH100 (10 HP, 389 cc) Engine Specs & Review

Tecumseh HH100 Engine Specs

The Tecumseh HH100 engine is a 23.7 cu·in (389 cc) single-cylinder air-cooled four-stroke internal combustion gasoline engine made by Tecumseh. 

This Tecumseh HH100 engine produced 10.2 PS (7.5 kW; 10.0 HP) horsepower. The Tecumseh HH100 engine cylinder bore is 84.1 mm (3.31 in), and the piston stroke is 69.8 mm (2.75 in). 

This Tecumseh HH100 engine can be fitted with Tecumseh or Walbro carburetor and solid-state ignition system (CDI). 

The Tecumseh HH100 engine has a horizontal PTO shaft, cast-iron cylinder block, an L-head (side valve) design, and cast-iron cylinder head. 

The breakdown of the Tecumseh HH100 engine code is as follows:

  • HH – Horizontal-Heavy Duty
  • 100 – 10.0 HP

Tecumseh HH100 Engine Specs

Tecumseh HH100 (10 HP, 389 cc) Engine Specs

Engine Specifications

Type4-stroke, L-head, single cylinder
Displacement389 cm3 (23.7 cu-in)
Max. horsepower10.2 PS (7.5 kW; 10.0 HP)
Max. torque (crank PTO)
Fuel systemCarburetor (Tecumseh or Walbro)
Cooling systemForced-air
Ignition systemSolid-state ignition system (CDI)
Lubricating systemSplash type
Starting systemRecoil or electric starter
Fuel usedUnleaded gasoline (octane number 86 or higher)

Tightening torque specs

Cylinder head bolt20.3-27.1 Nm; 2.07-2.76 kg·m; 15-20 ft·lb
Flywheel nut67.8-74.6 Nm; 6.9-7.6 kg·m; 50-55 ft·lb
Spark plug25-30 Nm; 2.55-3.06 kg·m; 18-22 ft·lb

Cylinder Head

Valve Arrangement:L-head (sidevalve)
Valve spring free length:47.879 mm (1.885 in)
Camshaft lobe diameter:33.134-33.236 mm (1.3045-1.3085 in)

Cylinder block

Bore x Stroke84.1 X 69.8 mm (3.31 x 2.75 in)
Sleeve internal diameter84.125-84.150 mm (3.312-3.313 in)
Piston skirt outer diameter84.023-84.074 mm (3.308-3.31 in)
Number of piston rings (compression / oil):2 / 1
Ring end gapTop0.178-0.508 mm (0.007-0.02 in)
Second0.178-0.508 mm (0.007-0.02 in)
Piston pin outer diameter17.457-17.463 mm (0.6873-0.6875 in)

Service Information

Valve clearance
Intake valve clearance0.254 mm (0.010 in)
Exhaust valve clearance0.508 mm (0.020 in)
Oil system
Oil typeAPI SF, SJ
Recommended oilSAE 30, 10-W30
Oil capacity1.4 liters (1.5 US.qts, 1.23 Imp. qts)
Ignition system
Spark plugChampion J-8
Spark plug gap0.763 mm (0.03 in)
Fuel system
TypeCarburetor (Tecumseh or Walbro)
Main adjustment screwTecumseh: 1-3/4 turns
Walbro: 1-1/2 turns off seat
Idle adjustment screwTecumseh: 1-1/4 turns
Walbro: 1-1/4 turns off seat

Also Check:

Final Words

This concludes our discussion of the Tecumseh HH100 (10 HP, 389 cc) Engine specs and review; however, if you have any questions regarding this article, please submit them in the comment section below. We will do our best to respond to you as soon as possible.

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