The M20026 Alternator Drive Pulley Puller is a precision-engineered removal tool designed specifically for Cummins L10 diesel engines equipped with threaded alternator drive pulleys. This tool provides a controlled, centered method for removing pulleys that are mounted with an interference fit on the accessory drive shaft.
Unlike plate-style or grooved pulley pullers, the M20026 uses a threaded engagement design, allowing it to screw directly into the pulley hub. This creates a rigid, slip-free connection between the tool and the pulley, ensuring force is applied evenly along the shaft axis during removal.
This design is particularly important for L10 engines, where alternator drive pulleys are often:
- Press-fit or taper-mounted
- Subject to heat cycling and corrosion
- Difficult to remove without damaging components
The M20026 functions as a simplified version of the plate-style puller (M20025), eliminating the backing plate and relying entirely on threaded engagement for stability.
Once installed, a forcing screw applies direct axial force, allowing the pulley to be removed smoothly without:
- Side loading
- Shaft scoring
- Pulley deformation
Because the force is applied in-line with the shaft, the tool preserves critical alignment surfaces and prevents bearing stress—making it ideal for precision service work on accessory drive systems.
Constructed from high-strength steel, the M20026 is built for repeated use in heavy-duty diesel environments, making it a core tool for technicians servicing Cummins L10 engines.
Key Features & Benefits
- Threaded Engagement Design: Screws directly into pulley hub for secure attachment
- Centered Pulling Force: Applies axial force along shaft centerline for safe removal
- No Backing Plate Required: Simplified design for threaded pulley applications
- Prevents Component Damage: Eliminates side load and protects shaft and bearings
- Application-Specific Fit: Designed for Cummins L10 threaded alternator drive pulleys
- Heavy-Duty Construction: Built for repeated high-load use
- Efficient Operation: Faster setup compared to plate-style pullers when applicable
Typical Applications
- Alternator drive pulley removal (threaded pulley type)
- Accessory drive system service
- Front gear housing repairs
- Engine teardown and rebuild procedures
- Heavy-duty truck and industrial diesel maintenance
Why It Matters
Cummins L10 engines use multiple pulley configurations, and using the wrong puller is one of the fastest ways to cause damage.
For threaded pulleys:
- Plate-style tools are unnecessary
- Jaw pullers introduce dangerous side load
- Improvised methods risk shaft and bearing damage
The M20026 is specifically designed for this configuration, ensuring:
- Clean, centered removal
- No distortion or thread damage
- Reliable reinstallation