Owner’s manual
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Are gas lawn mowers being phased out?
Gas walk-behind mowers like the Craftsman 917378401 are still widely used, but new-sales rules are tightening in some areas and many homeowners are shifting to battery-electric models for lower noise and simpler maintenance. Expect a gradual transition, not an overnight disappearance.
What “phased out” usually means
Most changes target new equipment sales and commercial use, not the mower you already own.
- Your existing gas mower can typically be used and maintained normally.
- Some regions restrict the sale of certain new gas-powered outdoor equipment.
- Retailers may stock fewer gas models over time as demand shifts.
- Parts support often continues for years because millions of gas mowers remain in service.
- Routine maintenance (blade, belt, wheels, oil) keeps older mowers running reliably.
What to do if you plan to keep your Craftsman 917378401
Use the maintenance and safety guidance in the Craftsman 917378401 owner’s manual. The manual also notes the mower ships without oil or gasoline and outlines common upkeep items like blades, belts, air filters, and spark plugs.
Quick upkeep checklist
- Use fresh fuel and avoid storing the mower with gasoline in the tank indoors.
- Keep the blade sharp; replace it when bent, cracked, or badly worn.
- Clean grass buildup from the deck and drive areas.
- Check drive wheels for free movement; clean debris if they bind.
- Tighten hardware after service (nuts, washers, bolts).
Parts that commonly keep older gas mowers going
If you are maintaining the drive system or cutting system, these model-matched parts are commonly involved:
| Mower area | Common symptom | Example model-matched part |
|---|---|---|
| Cutting | Poor cut, tearing grass | Premium blade 532406706 |
| Drive | Mower will not self-propel | Lawn mower ground drive belt, 3/8 x 33-9/16-in 532169778 |
| Wheels | Drive wheel binds or drags | Dust cover 581840401 |
Why it matters
Knowing the difference between “sales restrictions” and “ownership” helps you decide whether to maintain your current mower, stock common wear parts, or plan a future switch to electric based on noise, storage, and maintenance preferences.
Last updated: January 2026
Should I use 87 or 91 gas for lawn mower?
For the Craftsman gas walk-behind lawn mower model 917378401, we recommend using regular 87-octane unleaded gasoline for normal mowing. Higher octane (like 91) does not add power or improve reliability in this type of small engine; fresh, clean fuel matters most. See the 917378401 owner's manual for fuel and storage guidance.
What to use (and what to avoid)
- Use fresh 87-octane unleaded from a clean gas can.
- Avoid stale fuel; old gas is a top cause of no-start conditions.
- Keep fuel clean and dry; water or dirt in fuel leads to rough running and hard starting.
- If the mower will sit, use a fuel stabilizer and follow the storage steps in the manual.
- Do not store gasoline from one season to the next; refresh it before the first mow of the season.
Quick comparison: 87 vs 91 in a walk-behind mower
| Fuel choice | Best use | What you should expect |
|---|---|---|
| 87 octane (regular) | Everyday mowing | Normal starting, normal power, correct for most mower engines |
| 91 octane (premium) | Not needed for typical mower engines | No performance gain; costs more |
Why it matters
Most “mower fuel problems” are really fuel age and contamination problems, not octane problems. The manual’s troubleshooting guidance calls out stale fuel and water in fuel as common reasons a mower will not start, so focusing on fresh fuel prevents repeat issues.
If your mower won’t start after refueling
- Drain old fuel and refill with fresh gasoline.
- Check the air filter and spark plug condition.
- Make sure the operator presence control bar is held down for starting.
- Inspect the blade area; a loose blade or damaged adapter can contribute to starting issues (use the correct hardware such as a Lock nut 532409149 when servicing fasteners).
Last updated: January 2026
What model number is the Craftsman 917378401?
The model number for this Craftsman gas walk-behind lawn mower is 917.378401 (often written without the dot as 917378401). You can confirm it on the model tag and in the 917378401 owner's manual.
Where to find the model number on the mower
Check these common locations on Craftsman walk-behind mowers:
- On the rear of the mower deck near the discharge door
- On the deck top surface near the engine mounting area
- On a label near the handle mounting brackets
- In the printed manual cover pages
What the model number tells you (and why it matters)
Using the exact model number ensures we match the correct parts diagrams and parts for your mower, including items like the blade, drive belt, and height adjuster components.
| You might see it written as | What it means |
|---|---|
| 917.378401 | Full model format shown in the manual |
| 917378401 | Same model number without punctuation |
Quick parts examples tied to model 917378401
If you are ordering parts, the model number helps avoid mismatches. For example, this model uses parts such as:
- Premium blade 532406706 for cutting performance
- Lawn mower ground drive belt, 3/8 x 33-9/16-in 532169778 for self-propel drive
- Selector knob 532701037 for height adjuster control
Why it matters
A single digit difference in a Craftsman model number can change the deck, blade adapter, drive system, or handle hardware; using 917.378401 / 917378401 keeps parts selection accurate the first time.
Last updated: January 2026
