Prestolite Starter Motor 24V 11T CW M128739

This Prestolite starter motor is a new 24V unit with 11 teeth, clockwise rotation and a 12kW power rating. It is listed as part number M128739, with OEM number M128R3639SE, and is supplied as an insulated return starter for rotating electrical applications.

The unit uses a 3 hole starter mount with 126mm mount centres A, B and C, a 92mm flange diameter and 17mm mount hole diameter. Overall length is 376mm, the pinion sits 48mm at rest, and the pinion diameter is 56mm. These dimensions are important when checking physical interchange.

It is described as a Prestolite M128 Series, PLGR, heavy duty starter. The note supplied with the product states that for dual applications you do not mix M128 with M125, MS7 or 50MT starters, and that you must use 2x M128 starters. Flange or IMS relay may require rotation, and the unit is SAE3 mount insulated.

Key Features

• 24V new starter motor
• 11 tooth clockwise rotation
• 12kW power rating
• Insulated return design
• Rotatable nose
• Heavy duty M128 Series PLGR

Specifications

• Brand: Prestolite
• Part No.: M128739
• OEM Number: M128R3639SE
• Type: Starter motor
• Voltage: 24V
• Power Rating: 12kW
• Number of Teeth: 11
• Rotation: CW

Known application groups

• Atlas Copco: L830, MT42, MT431B, MT436B, MT436LP, MT6020, ST14, ST1520, ST1520LP, ST1530
• Bertram: 50, 570, 670
• Caterpillar: 12H, 140H, 140M, 143H, 14H, 14M, 16G, 16H, 16M, 245, 245B, 245D
• Other fitment listing includes CASE IH

Application and Buying Notes

Before ordering, match the part number M128739 and check the OEM reference M128R3639SE against the application you are servicing. The starter is a 24V, 11 tooth, clockwise rotating unit, so those basics need to align with the machine’s electrical setup and the original starter specification.

Physical dimensions matter on this model. Confirm the 3 hole mount layout, 126mm mount centres, 92mm flange diameter, 17mm mounting hole diameter, and 376mm overall length. The pinion at rest is 48mm, which is another useful check where clearance and engagement depth are tight.

This starter is listed as suitable for wet or dry clutch use and weighs 16kg. Those points help with handling and installation planning, but they do not replace a proper part number and dimensions check. If the flange or IMS relay needs rotation on your application, confirm the required orientation before fitting.

Before supply, the safest approach is to confirm the original unit details against the listed part number, voltage, output rating, mounting arrangement, and pulley configuration. That checking process is standard practice in the parts trade because visually similar units can still differ in service-critical ways.

For workshop, fleet, and equipment applications, accurate identification of part number M128739 helps avoid unnecessary freight, additional labour, and vehicle or machine downtime. Where the application is not straightforward, the original unit, OEM reference, or workshop records should be used as the primary confirmation point.

Relevant published details for this unit include Type STARTER MOTOR, Unit of Measure EACH, Warranty One Year, Mount Centres A 126mm, Mount Centres C 126mm, Number of Teeth 11, Pinion at Rest 48mm, Power Rating 12kW, Suits Unit Make Prestolite, Note M128 Series, PLGR, Heavy Duty For dual applications do not mix M128 with M125, MS7 or 50MT starters. You must use 2x M128 starters. Flange or IMS relay may require rotation. SAE3 Mount Insulated.

Additional published details for cross-checking include Starter Mount Type 3 Hole, Insulated Return Yes, Weight 16kg, Product Group 1 ROTATING ELECTRICAL, Part No. M128739, Brand PRESTOLITE, Description Prestolite Starter Motor 24V 11Th CW, Flange Diameter 92mm, Mount Centres B 126mm, Mount Hole Diameter 17.

Prestolite Starter Motor 24V 11Th CW. Part number M128739 should be checked first. Listed voltage is 24. These details form the core reference points used by parts interpreters when confirming the correct replacement.

For part number M128739, the normal identification sequence is part number, electrical rating, mounting arrangement, connector or terminal style, and pulley or drive details. Using those checkpoints helps confirm that the listed unit matches the service requirement rather than only looking similar.

For a starter motor in workshop, fleet, trade, agricultural, or construction service, the listed voltage 24 should be checked carefully. Incorrect selection can affect installation time, return freight, and equipment availability.

Available application references include ATLAS COPCO L830, ATLAS COPCO MT42, ATLAS COPCO MT431B, ATLAS COPCO MT436B, BERTRAM 50, BERTRAM 570. Even with application listings, final confirmation should still be based on the exact unit being replaced and the service requirements of the vehicle or machine.

The listed warranty is One Year. Warranty terms should be considered alongside correct application and part identification, as warranty does not replace fitment confirmation.

Compatibility note: Confirm fitment by matching part number M128739, OEM number M128R3639SE, the 24V 11 tooth CW specification, and the listed mounting dimensions before ordering. If your application uses a dual starter arrangement, do not mix M128 with M125, MS7 or 50MT starters.

FAQ

What is the voltage of this starter motor?

It is a 24V starter motor. For this listing, part number M128739 is the main reference point. Listed voltage is 24. Published fitment references include ATLAS COPCO L830, ATLAS COPCO MT42, ATLAS COPCO MT431B. These details should still be checked against the original unit before ordering.

How many teeth does the pinion have?

The starter has 11 teeth. For this listing, part number M128739 is the main reference point. Listed voltage is 24. Published fitment references include ATLAS COPCO L830, ATLAS COPCO MT42, ATLAS COPCO MT431B. These details should still be checked against the original unit before ordering.

What is the rotation direction?

It is clockwise rotation, shown as CW. For this listing, part number M128739 is the main reference point. Listed voltage is 24. Published fitment references include ATLAS COPCO L830, ATLAS COPCO MT42, ATLAS COPCO MT431B. These details should still be checked against the original unit before ordering.

Is this a new or remanufactured unit?

It is listed as new. For this listing, part number M128739 is the main reference point. Listed voltage is 24. Published fitment references include ATLAS COPCO L830, ATLAS COPCO MT42, ATLAS COPCO MT431B. These details should still be checked against the original unit before ordering.

What are the main mounting dimensions?

The starter has a 3 hole mount, 126mm mount centres A, B and C, a 92mm flange diameter, and 17mm mount hole diameter. For this listing, part number M128739 is the main reference point. Listed voltage is 24. Published fitment references include ATLAS COPCO L830, ATLAS COPCO MT42, ATLAS COPCO MT431B. These details should still be checked against the original unit before ordering.

What should I check before buying?

Match part number M128739 and OEM number M128R3639SE, then confirm the 24V, 11 tooth CW specification and the listed dimensions, especially where dual applications or flange rotation are involved. For this listing, part number M128739 is the main reference point. Listed voltage is 24. Published fitment references include ATLAS COPCO L830, ATLAS COPCO MT42, ATLAS COPCO MT431B. These details should still be checked against the original unit before ordering.