Owner’s manual
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How old is my mower by serial number?
For Craftsman walk-behind mower model 917376391, the serial number identifies your exact unit for parts and service; the most accurate way to determine age is to use the date of purchase you recorded and keep the serial number for service records. See the 917376391 owner's manual.
Where to find the serial number on model 917376391
The model and serial numbers are on a decal on the rear of the lawn mower housing.
- Look at the back of the mower deck (rear housing), not the handle.
- Brush off grass and dirt so every character is readable.
- Write the model number and serial number exactly as shown.
- Take a clear photo of the decal for your records.
How we recommend estimating the mower’s age
Because serial-number date decoding is not consistent across all Craftsman walk-behind mowers, we use these reliable methods.
- Use your recorded purchase date (manual, receipt, or service invoice) as the mower’s age baseline.
- If you have maintenance logs, use the first season of use plus yearly service history.
- Use the serial number to ensure you order correct parts for your exact configuration.
Quick comparison
| Method | What you get | Best for |
|---|---|---|
| Purchase date | Calendar age | Service records, ownership timeline |
| Maintenance history | Usage-based age | Tune-ups, wear-item planning |
| Serial number | Unit identification | Correct parts matching and service |
Why it matters
Knowing the mower’s age helps us align maintenance timing (oil changes, blade service, drive adjustments) with how the mower is actually used, and it keeps parts ordering accurate when multiple versions exist.
Last updated: January 2026
What model number is a Craftsman 6.75 lawn mower?
Many Craftsman mowers labeled “6.75” are identified by the full model number on the mower’s ID label; for this Craftsman walk-behind mower, the model number is 917.376391 (often shown without the dot as 917376391). Confirm it on the product label and in the 917376391 owner's manual.
Where to find the model number on the mower
We recommend checking these common locations on Craftsman walk-behind mowers:
- Rear of the deck near the discharge opening
- Top of the deck near the engine mounting area
- On the handle support or rear door area
- On a sticker or metal tag with “Model No.” and “Serial No.”
- In the manual cover page (often lists the model number clearly)
“6.75” vs. model number: what’s the difference?
“6.75” is typically an engine series/marketing label, not the mower’s full model identifier. The mower model number is what you need for parts lookup (blade, drive parts, control cable) and diagrams.
| What you see | What it means | What to use for parts |
|---|---|---|
| 6.75 / 675 Series | Engine series label | Not enough by itself |
| 917.376391 (or 917376391) | Mower model number | Use this |
Parts that commonly require the exact model number
Using the correct model number helps us match the right fit for items like:
- Blade and blade adapter (deck and crankshaft fit)
- Drive system parts (belt, pulley, transmission)
- Control cables and handle components
- Rear door, baffles, and discharge/mulch hardware
If you are replacing the blade on this model, match it to the husqvarna lawn mower 22-inch deck 3-in-1 blade 532421825 listed for Craftsman model 917376391.
Why it matters
Craftsman walk-behind mowers can share similar engine labels (like 6.75) across multiple mower builds. The model number (917.376391) is what ties your mower to the correct parts diagrams and OEM replacement parts.
Last updated: January 2026
What octane gas should I use in my lawn mower?
For the Craftsman lawn mower model 917376391, we recommend using fresh regular unleaded gasoline (87 octane) for normal mowing. Higher octane does not add power in small engines; the bigger priority is clean, fresh fuel and proper storage practices outlined in the 917376391 owner's manual.
What to use (and what to avoid)
- Use 87 octane regular unleaded from a busy station (fresher fuel).
- Avoid old fuel; stale gas is a top cause of hard starting and rough running.
- Avoid leaving fuel sitting in the tank for long periods.
- Be cautious with alcohol-blended fuels; the manual notes they can attract moisture and cause fuel separation and acids during storage.
- Never pour engine or carburetor cleaner into the fuel tank; the manual warns this can cause permanent damage.
Storage guidance (important for fuel quality)
The manual recommends emptying the fuel system before storage of 30 days or longer to help prevent fuel-system damage.
Basic storage steps:
- Empty the gas tank.
- Start the engine and let it run until the fuel lines and carburetor are empty.
- Refill with fresh fuel at the start of the next season.
Quick comparison
| Fuel choice | Good for 917376391? | Why |
|---|---|---|
| 87 octane regular unleaded | Yes | Correct octane for typical small engines; reliable and cost-effective |
| 89 to 93 octane premium | Not needed | Does not improve performance for this mower’s engine |
| Old/stale gasoline | No | Can cause starting and running problems |
| Alcohol-blended fuel stored for long periods | Risky | Can attract moisture and separate during storage |
Why it matters
Using the right fuel and storing it correctly helps protect the carburetor and fuel lines, reduces no-start issues after storage, and keeps your Craftsman walk-behind mower running consistently.
Last updated: January 2026
