IMI99 Aftermarket Yanmar Inboard Starter Motor 2QM15, QM15, 2TM15, 2T73, YA, YC | Sawley's Select Marine Parts

🔧 Product Description

Aftermarket Yanmar QM/TM/YA/YC Gear-Reduction Starter Motor - Part Number: IMI99

New aftermarket Denso-motor offset gear-reduction starter for early Yanmar 2QM15, QM15, 2TM15, 2T73, YA and YC marine diesel engines. The assembly replaces Yanmar 124070-77010 and uses a 12-volt, approximately 1.2kW, clockwise, 11-tooth drive.

⚙️ Key Features

• 12-volt marine diesel starting system

• Approximately 1.2kW rated output

• Clockwise rotation viewed from the drive end

• 11-tooth pinion with approximately 33.5mm gear diameter

• Two-bolt offset gear-reduction construction

• Approximately 89mm mounting pilot

🧰 Assembly Contents

• 1 × Complete gear-reduction starter motor assembly - Part Number: IMI99

• 1 × Integrated starter solenoid

• 1 × Installed 11-tooth pinion and overrunning clutch

• 1 × Installed Denso motor, reduction drive, brush-holder and mounting nose

• Mounting bolts and external battery cables are supplied separately unless stated

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• IMI99 → Aftermarket replacement for Yanmar 124070-77010

• 124070-77010 → Yanmar OEM starter reference

OEM / Related Numbers:

• IMI99

• Yanmar 124070-77010

• Hitachi S114-219

• Hitachi S114-230

• Hitachi S114-230A

Aftermarket / Verified Equivalents:

• IMI Hi-Torque: IMI99

• Hitachi: S114-219 / S114-230 / S114-230A

• Aftermarket Denso-motor gear-reduction replacement for Yanmar 124070-77010

🚤 Compatibility

Commonly used on:

• Early Yanmar small marine-diesel starting systems using the 124070-77010 mounting and ring gear

Typically suits:

• Yanmar 2QM15

• Yanmar QM15

• Yanmar 2TM15

• Yanmar 2T73

• Yanmar YA-series engines using starter 124070-77010

• Yanmar YC-series engines using starter 124070-77010

• HP Range: Engine-model dependent

• Engine Type: One- or two-cylinder naturally aspirated marine diesel, model dependent

• Year Range: Legacy Yanmar production; engine and flywheel configuration controlled

• Serial / Model Identification: Confirm 12V, 1.2kW, 11 teeth, clockwise rotation, approximately 89mm pilot, two-bolt mounting and Yanmar 124070-77010.

🔌 Function

The offset reduction drive multiplies motor torque to crank the early high-compression Yanmar diesel. The solenoid engages the 11-tooth pinion and switches battery power to the motor.

Common signs of failure:

• Starter turns slowly despite a charged battery

• Solenoid clicks but the motor does not rotate

• Pinion spins without engaging the flywheel

• Grinding caused by incorrect pinion or pilot dimensions

• Intermittent operation from worn brushes or contacts

• Reduction-gear wear, corrosion or excessive shaft/bearing play

📦 Condition

• Brand-new aftermarket replacement starter motor

• New and unused

• Supplied in suitable manufacturer or equivalent protective packaging