Liftmaster K144B0018 Idler Pulley (2" OD, 1/2"B) Chamberlain Garage Openers
The LiftMaster K144B0018 is an idler pulley used in select LiftMaster and Chamberlain garage door opener drive systems. An idler pulley does not power the opener by itself; instead, it helps guide the drive path and maintain proper alignment so the opener can move smoothly.
LiftMaster compatibility information specifically lists the ATS211 and ATS211R models. Other catalog descriptions may describe the part more broadly for LiftMaster and Chamberlain openers, but model-specific confirmation is still needed before ordering.
A worn idler pulley may create squealing, grinding, uneven drive movement, or belt/drive misalignment. When replacing it, inspect the surrounding drive parts, rail, and carriage so the new pulley is not damaged by another worn component.
Features & Specifications
| Feature / Specification | Details |
|---|
| Manufacturer | LiftMaster |
| Product Type | Idler pulley |
| Part Number | K144B0018 |
| Application | Drive-system idler pulley replacement |
| Compatible Operator Type | Select LiftMaster and Chamberlain garage door openers |
| Specific Model References | ATS211 and ATS211R |
| Outside Diameter | 2 inch |
| Bore | 1/2 inch |
Compatible With
Common Compatible Models
- LiftMaster ATS211 garage door opener
- LiftMaster ATS211R garage door opener
Additional Model Families to Verify
- Select Chamberlain equivalents using the K144B0018 / 144B0018 idler pulley
- Select LiftMaster/Chamberlain garage door opener applications where the parts diagram calls for 144B0018
Important Compatibility Notes
- Confirm outside diameter, bore size, and pulley function
- Do not confuse an idler pulley with a motor pulley
- Match by model and parts diagram before ordering
Also Known As / Related Part Numbers
- K144B0018
- 144B0018
- 144B18
- LiftMaster idler pulley
- LiftMaster 2 inch idler pulley
- Chamberlain idler pulley
Technician Note
A seized or rough idler pulley can damage drive components. Spin the old pulley by hand after removal and inspect for bearing roughness, wobble, or visible cracking.
Before Ordering Checklist
- Confirm the opener model is ATS211, ATS211R, or a confirmed compatible model
- Match the original pulley to K144B0018 or 144B0018
- Confirm 2 inch outside diameter and 1/2 inch bore
- Inspect the drive path for wear or misalignment
- Confirm the pulley mounting hardware is reusable or order hardware separately if needed
Professional Advisory
Disconnect opener power before servicing moving drive components. Do not operate the opener with exposed or loose drive hardware.
Product Questions and Answers
Which models are specifically listed for K144B0018?
LiftMaster lists ATS211 and ATS211R garage door openers as compatible models.
Is K144B0018 a motor pulley?
No. It is an idler pulley used to guide or support the drive path, not the pulley mounted directly to the motor shaft.
What are the related part numbers?
Common related numbers include K144B0018, 144B0018, and 144B18.
What size is this pulley?
It is listed as a 2 inch outside diameter pulley with a 1/2 inch bore.
When should the idler pulley be replaced?
Replace it when the pulley is cracked, noisy, seized, wobbling, or no longer keeping the drive system aligned.
