Craftsman 919166440 air compressor Parts

No. The Craftsman air compressor model 919166440 is covered by a full one-year warranty for defects in materials or workmanship from the purchase date; if it is used commercially or as a rental, coverage is 90 days. Warranty details and limitations are listed in the 919166440 owner's manual.

What the warranty covers (and what it does not)

The one-year warranty is specifically for defects in material or workmanship under normal use.

• Covers manufacturing defects that cause the compressor to fail
• Applies from the original purchase date (keep your receipt)
• Commercial or rental use shortens coverage to 90 days
• Does not cover normal wear items or damage from misuse, poor maintenance, or improper operation

Quick warranty comparison

Use type	Warranty length	What triggers coverage
Homeowner/consumer use	1 year	Defect in material or workmanship
Commercial or rental use	90 days	Defect in material or workmanship

Why it matters

Warranty length affects how you plan maintenance and repairs. For example, running the compressor continuously can shorten component life; the manual recommends maintaining a 50% to 75% average duty cycle (about 30 to 45 minutes of run time per hour) to help prolong pump life.

Helpful next steps

• Confirm your purchase date and whether the unit was used commercially
• Review the warranty section and operating guidance in the 919166440 owner's manual
• If you need replacement parts, start with the parts list for model 919166440, or search by model number on Sears PartsDirect

Last updated: February 2026

Yes. Many electric air compressors include a motor overload reset (thermal protector) that trips if the motor overheats or is under heavy load. On the Craftsman 919166440, the primary operator control is the On/Auto/Off switch; use the 919166440 owner's manual to identify the exact control locations on your unit.

What you will see on the Craftsman 919166440

Your compressor is designed to run automatically using the pressure switch and On/Auto/Off switch. If the motor stops unexpectedly, treat it like an overload or power interruption first.

• Set the On/Auto/Off switch to Off.
• Let the motor cool down for 15 to 30 minutes.
• Verify the outlet is supplying power (try a different tool or lamp).
• Reduce load: pull the regulator knob out and turn it counterclockwise to lower outlet pressure.
• Restart by switching to On/Auto.

Quick checks before you “reset” anything

These steps prevent repeat trips and help the compressor start easier.

• Tank pressure: If the tank is near cut-out pressure, the motor may struggle to restart under load.
• Regulator setting: Keep outlet pressure low during startup, then raise it after the motor is running.
• Drain valve: Drain condensation after use; water in the tank can contribute to corrosion and performance issues.
• Hose/accessory load: Disconnect air tools and hoses to see if the compressor starts unloaded.
• Air leaks: Listen for hissing at fittings, the safety valve, or the tank drain.

Common “reset button” locations (typical)

Different builds place the overload reset in different spots. Use this as a practical guide while you compare to your unit.

What you are looking for	Typical location	What it does
Thermal overload reset button	On or near the motor housing, sometimes under a small cover	Restores power after an overheat trip
On/Auto/Off switch	Control panel area	Turns compressor power on/off for normal operation
Pressure switch	Near the air line from pump to tank	Starts/stops motor at cut-in and cut-out

Why it matters

If an overload reset trips repeatedly, the compressor is protecting the motor from damage. The fix is usually reducing starting load (lower regulator pressure, start with tools disconnected) or correcting an airflow/pressure problem.

Related DIY help

• Air compressor won't start
• Air compressor won't start with a full air tank

You can look up diagrams and replacement parts for Craftsman 919166440 on the model parts list, or search by model number on Sears PartsDirect.

Last updated: February 2026

“4.0 SCFM at 90 PSI” means a tool or compressor is rated to deliver (or require) 4.0 standard cubic feet of air per minute while operating at 90 PSI. For Craftsman air compressor model 919166440, our manual lists 3.5 SCFM @ 90 PSIG, so a 4.0 SCFM @ 90 PSI tool demand is above this compressor’s delivered airflow at that pressure.

What SCFM and PSI mean

• SCFM (standard cubic feet per minute): airflow measured under standard conditions so compressor output can be compared consistently.
• PSI (PSIG): pressure level at the outlet; many air tools are rated around 90 PSI.
• SCFM always drops as PSI rises: higher pressure takes more work, so delivered airflow is lower at 90 PSI than at 40 PSI.

You can verify the glossary definitions and the model’s published airflow ratings in the 919166440 owner's manual.

How to use “SCFM @ 90 PSI” to size tools

Use the tool’s requirement at the same pressure as the compressor rating.

• If the tool needs 3.0 SCFM @ 90 PSI, model 919166440 keeps up in normal use.
• If the tool needs 4.0 SCFM @ 90 PSI, expect the motor to run frequently and the regulated pressure to sag during continuous use.
• If the tool needs 5.0 SCFM @ 90 PSI, the compressor will not maintain pressure under steady demand.

Quick match table

Tool requirement (at 90 PSI)	What you’ll see on 919166440	Best use case
Below 3.5 SCFM	Stable pressure, normal cycling	Nailers, blow gun, light spray
Around 3.5 SCFM	Borderline on long runs	Short bursts, pauses between cycles
Above 3.5 SCFM	Pressure drop during use	Upgrade compressor or reduce demand

Why it matters

When a tool’s SCFM demand is higher than the compressor’s SCFM at that PSI, tank pressure and regulated outlet pressure drop while you work. That shows up as weaker tool performance and longer run time.

Related DIY help

• Air compressor won't build tank pressure
• Air compressor air leaks

Parts and diagrams

We provide parts diagrams for model 919166440; you can also search by model number on Sears PartsDirect.

Last updated: February 2026

For the Craftsman 919166440 air compressor, the most common cause of failure is overheating and premature wear caused by restricted ventilation and extended run time. The manual specifically warns that blocking ventilation openings can cause serious overheating; leaks and pressure-control problems are also frequent failure triggers.

What to check first on model 919166440

• Ventilation and placement: keep the unit in an open area with clear airflow; do not place objects on or against the compressor.
• Duty cycle and tool demand: if the compressor runs nearly nonstop to keep up with an air tool, heat builds quickly.
• Air leaks: loose fittings, leaking seals, or leaks between the head and valve plate increase run time.
• Pressure switch and safety valve behavior: if the motor does not shut off at cut-out pressure or the safety valve pops, stop using the compressor.
• Check valve restriction: can contribute to poor pressure performance and hard starting.

Quick, safe troubleshooting steps

Follow the shutdown and safety steps in the 919166440 owner's manual before servicing.

• Turn the switch to Off, unplug the cord.
• Bleed tank pressure completely.
• Let the pump and motor cool.
• Restore proper clearance around ventilation openings.
• Soap-test fittings for bubbles; tighten fittings just until the leak stops (do not overtighten).

Symptom-to-cause guide

Symptom	Common cause	What we recommend
Safety valve pops or unit will not shut off	Pressure switch/control issue	Stop use; correct the pressure control problem before running
Won’t build tank pressure	Air leak, valve plate/head leak, restricted check valve	Leak test first; then inspect valve components
Pressure drops when using a tool	Normal small drop, tool SCFM too high, leak	Adjust regulator under flow; verify tool air requirement

Why it matters

Restricted airflow and leaks force longer run times, which raises operating temperature and accelerates wear on the pump and seals. Keeping ventilation clear and fixing leaks early prevents most breakdowns.

Helpful DIY guidance

• Air compressor air leaks
• Air compressor won't build tank pressure

For replacement parts, use the model diagrams and parts list for Craftsman 919166440, or search by model on Sears PartsDirect.

Last updated: February 2026