Craftsman 917375940 rotary lawn mower Parts

For Craftsman rotary lawn mower model 917375940, use unleaded regular gasoline (87 octane is fine). The key is using fresh, clean fuel and the correct oil; our 917375940 owner's manual lists “unleaded regular only” for this mower.

• Use fresh unleaded regular gasoline from a clean container.
• Use fuel that is not stale (old fuel is a top cause of hard starting and rough running).
• Avoid mixing oil into the gas (this is a 4-cycle mower; oil goes in the crankcase).
• Avoid fuel contaminated with water, dirt, or rust.
• If you store fuel, keep the can sealed and replace it if it starts to rust.

Higher octane (89 or 91) is mainly for engines that knock under load. Most walk-behind mower engines are designed to run correctly on regular unleaded; higher octane typically does not add power or improve reliability by itself.

Using the correct fuel for your Craftsman 917375940 helps the engine start easier, run cooler, and avoid carburetor problems caused by stale or contaminated gasoline. For storage practices that protect the fuel system, follow the 917375940 owner's manual.

Last updated: February 2026

On the Craftsman rotary lawn mower model 917375940, the most common problems are no-start, loss of power, and poor or uneven cutting. These issues usually trace back to fuel quality, airflow (dirty air filter), ignition (spark plug/wire), or grass and debris buildup under the mower deck; our 917375940 owner's manual troubleshooting chart covers these exact symptoms.

• Does not start: stale fuel, dirty air filter, spark plug wire off, bad spark plug, or the control bar not held against the handle.
• Loss of power: cutting too much grass at once, deck packed with clippings, dirty air filter, or walking speed too fast.
• Poor cut (uneven): worn/bent/loose blade, uneven wheel height settings, or debris buildup under the housing.
• Hard to push in tall grass: cutting height set too low or grass is too tall and thick.
• After hitting an object: blade or blade adapter can loosen or break; stop and inspect before restarting.

1. Safety and controls: Hold the control bar firmly to the handle while starting.
2. Fuel: Drain stale gas and refill with fresh gasoline if it has been sitting.
3. Airflow: Clean or replace the air filter; restricted airflow causes hard starting and power loss.
4. Ignition: Confirm the spark plug wire is fully seated; replace the spark plug if fouled.
5. Deck condition: Tip the mower safely and remove packed grass from under the deck.

Running with stale fuel, a clogged deck, or a loose blade can quickly turn a simple tune-up into bigger repairs. The manual also notes to stop and inspect after striking an object, and to avoid changing engine governor settings.

Last updated: February 2026

Most walk-behind gas lawn mowers, including the Craftsman 917375940, last 8 to 15 years with normal homeowner use and consistent maintenance. Regular oil changes, cleaning the mower deck, and proper off-season storage are the biggest factors that keep the engine and drive system running longer.

These ranges reflect what we see most often with routine maintenance and non-commercial use.

From the Craftsman 917375940 maintenance guidance, these habits directly protect engine life and performance.

• Change engine oil every 25 hours of operation or at least once per year
• Check oil level before starting and during extended mowing sessions
• Clean the underside of the mower after each use to prevent grass buildup and corrosion
• Avoid spraying water into the engine area (water intrusion shortens engine life)
• Prepare for storage if it will sit 30 days or more (clean, lubricate, inspect fasteners)

For the exact maintenance schedule and specs (oil capacity, spark plug type, blade bolt torque), use the 917375940 owner’s manual.

A mower is still worth maintaining when the core systems are solid.

• Starts reliably and runs smoothly after tune-up items (oil, spark plug, air filter)
• Deck is structurally sound (no major rust-through or cracking)
• Wheels and height adjusters hold position
• Self-propelled drive engages consistently (if equipped)
• Repairs are limited to normal wear parts (cables, wheels, pulleys)

A mower’s lifespan is mostly about engine lubrication, cooling/cleanliness, and storage. Grass and debris buildup makes the engine run hotter, and neglected oil changes accelerate internal wear. Keeping up with routine care saves money and prevents mid-season breakdowns.

Last updated: February 2026

The model number is 917.375940 (often written without the dot as 917375940) for this Craftsman rotary lawn mower. You can confirm it on the model identification pages in the 917375940 owner's manual.

We recommend matching the number on the mower’s ID label to the manual and parts diagrams.

• Check the ID label on the mower deck (top surface near the engine) or rear deck area
• Look for “MODEL NUMBER 917.375940” on the label
• Write down the full number exactly as shown (including any dots)
• Use the model number when ordering parts like a drive control cable or wheel
• If the label is dirty, wipe it clean so every digit is readable

These are the same model number written two ways.

Some online references list a retail mower name (for example, “M140”) or a different manufacturer’s internal model family. For Sears PartsDirect parts lookup and diagram accuracy, the correct identifier for this page is Craftsman model 917375940.

Using the exact model number ensures you get the right parts and diagrams for your mower’s configuration (drive system, handle hardware, and deck components), which prevents ordering the wrong pulley, cable, or fasteners.

Last updated: February 2026

Craftsman model 917375940 is identified by its model number, not a date code; the model number itself does not tell the year it was built. For the most accurate manufacturing date, use the identification information and specifications shown in the 917375940 owner's manual.

On Craftsman walk-behind mowers, the manufacturing date is typically tied to the engine or a separate product/serial label, not the 917-prefix model number.

• Check the mower deck or rear flap area for a product label with a serial number.
• Check the engine shroud (blower housing) for an engine model and code/date.
• Write down all numbers exactly as shown (letters and dashes matter).
• Compare the engine code format to the engine maker’s date-code chart (common on Briggs & Stratton engines).
• Use the parts diagrams in the manual to confirm you are reading the correct label for this mower.

The documentation confirms the mower is a Craftsman rotary lawn mower, model 917.375940, and provides parts breakdowns and service guidance, but it is not a “year decoder.” Use it to verify you have the correct model and to match components.

Getting the correct year/build date helps when you are matching engine parts, selecting the right blade, or diagnosing drive issues (belt, pulley, transmission) because small design changes can happen within the same model family.

Last updated: February 2026

Yes, WD-40 can reduce grass sticking under the deck on your Craftsman 917375940 rotary lawn mower by leaving a slick film, but it is a short-term fix. For best results, we focus on keeping the mower housing clean and dry between cuts, as outlined in the 917375940 owner's manual.

The manual’s core guidance is simple: keep the mower housing free of built-up grass and clean the underside after each use.

• Shut the engine off and wait for the blade to stop before servicing
• Disconnect the spark plug wire before cleaning under the deck
• Scrape the underside to remove packed grass and debris (a plastic scraper or putty knife works well)
• Avoid mowing wet grass when possible; wet clippings stick and clump
• Raise the cutting height in tall grass to reduce clumping, then mow again lower if needed
• Keep the top of the engine clear of clippings so airflow stays strong

Use it only on a cool, off mower and treat it as a light coating, not a soak.

• Clean and dry the underside first (spraying over wet grass paste does not help)
• Apply a light, even film to the underside of the deck (avoid belts, pulleys, and drive areas)
• Keep spray away from the muffler and hot engine surfaces
• Reapply as needed; it wears off quickly, especially in damp conditions

Grass buildup reduces airflow under the deck, hurts cut quality, and can accelerate corrosion. Regular cleaning also helps you spot issues early, such as debris around the drive system.

Last updated: February 2026