How to look up Craftsman model number?
To look up the model number for your Craftsman 1/2-hp AC motor (model 11312791), find the model tag on the motor housing and use that exact number when searching for parts and diagrams on Sears PartsDirect.
Where to find the model number on a Craftsman motor
On power tools and standalone motors, the model number is usually on a label or stamped plate attached to the motor body.
Check these common spots:
- The outside of the motor housing (side or top)
- Near the wiring cover or junction box
- Close to the on/off switch area (if equipped)
- Near the mounting base or foot
- On the capacitor cover (if your motor has an external capacitor)
How to use the model number to look up parts
Once you have the model number, match it exactly (including any dashes or extra digits) to pull the correct parts list.
Use this quick checklist:
- Write the model number exactly as shown on the tag
- Also note any type, spec, or serial number listed (helps confirm the right version)
- Search by the full model number first (for example, 11312791)
- Compare the product type shown in results to your tool (for this page: 1/2-hp AC motor)
Model number vs. part number (what’s the difference?)
| Item | What it identifies | Where you’ll see it |
|---|---|---|
| Model number | The complete tool or motor | Motor tag/plate |
| Part number | A specific replacement component | Parts list, diagrams, part packaging |
| Serial number | Your unit’s production run | Motor tag/plate |
Why it matters
Using the exact model number prevents ordering the wrong electrical parts (like switches, capacitors, cords, or brushes) that may look similar but have different ratings, mounting, or wiring.
Last updated: February 2026
Where can I buy Craftsman replacement parts?
You can buy replacement parts for your Craftsman model 11312791 (1/2-hp AC motor) by using the model-based parts lookup on Sears PartsDirect. This is the most reliable way to match parts to your exact model number and avoid ordering a look-alike that will not fit.
Best way to get the right part for model 11312791
- Use the exact model number 11312791 when searching (match every digit).
- Compare the part description to what you see on your motor (switch, capacitor, cord, bearings, etc.).
- If your motor has a data plate with additional numbers (type, spec, or code), keep those handy for cross-checking.
- Order by the model-based parts list whenever possible to reduce returns.
What you will typically need before ordering
| What to gather | Where to find it | Why it matters |
|---|---|---|
| Model number (11312791) | Motor nameplate or your paperwork | Ensures correct parts breakdown |
| Voltage and amperage | Nameplate | Helps match electrical components |
| Shaft details (diameter/length) | Measure the shaft | Helps match pulleys, bearings, and couplers |
| Photos of wiring and terminals | Take pictures before disassembly | Prevents miswiring during reassembly |
Why it matters
Power tool motors often have similar-looking components that are not interchangeable. Ordering by the exact Craftsman model number 11312791 helps ensure the replacement part matches the motor’s mounting, wiring connections, and electrical ratings.
Helpful DIY reference for electrical checks
If you are troubleshooting before buying parts, use how to use a multimeter to test electrical parts video to confirm whether common items like a switch, cord, capacitor, or thermal protector are actually failed.
Last updated: February 2026
What is the average lifespan of 11312791?
A Craftsman 11312791 1/2-hp AC motor typically lasts 10 to 15 years with normal use and good airflow. Lifespan is driven more by load, heat, and bearing condition than by age alone, so maintenance and operating habits matter.
Typical lifespan and what affects it
Most fractional-horsepower AC motors like the Craftsman 11312791 reach their full service life when they stay cool, clean, and properly loaded.
- Duty cycle: frequent starts and long run times shorten life
- Heat: blocked vents, sawdust buildup, or high ambient temps accelerate wear
- Load: over-belt tension, binding tools, or oversized loads stress bearings and windings
- Power quality: low voltage and loose connections increase amperage and heat
- Storage: moisture leads to corrosion and insulation breakdown
Quick health checks (no special tools)
Use these checks to judge whether your motor is near end-of-life.
- Spins freely by hand (power disconnected) with no grinding
- Starts quickly without a long hum
- Runs without a burning smell
- Housing is warm but not excessively hot after normal use
- No unusual vibration, squeal, or rattling
Symptoms and what they usually mean
| Symptom | Common cause | What to do next |
|---|---|---|
| Hums but won’t start | start circuit/capacitor issue, stuck load | remove load, inspect wiring, test components |
| Overheats and trips | overload, poor ventilation, low voltage | reduce load, clean vents, check connections |
| Loud bearing noise | worn bearings | plan bearing service or motor replacement |
| Slow or weak power | voltage drop, winding wear | verify supply, inspect cord/switch |
Why it matters
A motor that is overheating or struggling to start can damage connected power tool components and create a safety risk. Catching airflow, wiring, and load issues early often adds years of service.
For electrical troubleshooting steps, we recommend [how to use a multimeter to test electrical parts video].
Last updated: March 2026





