How old is my mower by serial number?
On Craftsman walk-behind mower model 917377844, the serial number is recorded from the decal on the rear of the mower housing; that serial number helps identify the unit, but the most reliable way to determine the mower’s age is to match the serial number to the date-coding format shown in the 917377844 owner's manual.
We use the same location the manual calls out for recording it.
- Look for a decal on the rear of the lawn mower housing.
- Write down the serial number exactly as shown.
- Record the date of purchase too (helpful for service history).
- If the decal is dirty, wipe it gently so every digit is readable.
Serial formats vary by manufacturer and production run, so we decode it by looking for a date pattern in the serial.
- Check the first 4 to 6 characters for a date-style code (common patterns include YYMM, MMYY, or MMDDYY).
- If you see a clear month and year grouping, that typically indicates the manufacture month and year.
- If the serial is all letters and numbers with no obvious date grouping, use the serial to cross-reference the model’s documentation and parts breakdown in the 917377844 owner's manual.
| What you see in the serial | What it usually means | Example interpretation |
|---|---|---|
| 4 digits that look like YYMM | Year and month | 2105 = May 2021 |
| 4 digits that look like MMYY | Month and year | 0521 = May 2021 |
| 6 digits that look like MMDDYY | Month, day, year | 051521 = May 15, 2021 |
Knowing the mower’s age helps us choose the right maintenance plan (oil, spark plug, blade service) and reduces the chance of ordering the wrong Craftsman parts when there were mid-year design changes.
Last updated: January 2026
Should I use 87 or 91 gas for lawn mower?
For the Craftsman lawn mower model 917377844, we recommend using 87-octane (regular) unleaded gasoline for normal operation. Higher octane (like 91) does not add power in small mower engines; the bigger priority is using fresh, clean fuel and storing it correctly per the 917377844 owner's manual.
- Use 87 octane unleaded gasoline for everyday mowing.
- Avoid stale fuel; old gas is a common reason a mower will not start.
- Keep fuel containers clean and replace rusty cans; rust and dirt cause fuel system problems.
- Do not store gasoline from one season to the next.
- Let the engine cool before storing the mower indoors with fuel in the tank.
| Fuel choice | What it changes | What it does not change | Best use case |
|---|---|---|---|
| 87 octane (regular) | Normal starting and running | Does not reduce maintenance needs | Standard mowing, everyday use |
| 91 octane (premium) | Usually nothing noticeable | Does not “clean” the carburetor by itself | Only if your engine label specifically requires it |
Stale fuel and fuel contamination show up as “won’t start” symptoms. Before replacing parts, we use these checks:
- Confirm you have fresh fuel in the tank.
- Check the fuel valve lever (if equipped) is in the ON position.
- Inspect the air filter for heavy dirt buildup.
- Verify the spark plug wire is firmly connected.
- If fuel is old, drain it safely and refill with fresh 87-octane.
For step-by-step no-start diagnosis, use lawn mower wont start troubleshooting video fuel ignition and compression.
Using the right fuel is less about octane and more about reliability. Fresh 87-octane fuel helps prevent hard starting, rough running, and fuel-system issues that can shorten engine life and increase tune-up frequency.
Last updated: January 2026
What are the most common issues with 917377844?
On the Craftsman 917377844 gas walk-behind mower, the most common problems are drive and wheel issues (self-propel not pulling), poor cutting or vibration, and bagging or discharge problems. These usually trace to wear parts like the blade, transmission drive components, or chute and deflector hardware.
- Self-propel quits or slips: worn drive components, loose hardware, or a failing transmission
- Mower vibrates or cuts unevenly: bent or dull blade, loose fasteners, debris buildup under the deck
- Grass clumps or won’t bag well: clogged chute, damaged bag or frame, misaligned deflector
- Wheels wobble or don’t track: worn wheel, missing retaining ring, worn bearing
- Controls feel loose: worn handle/control hardware or linkage parts
- Shut the engine off and disconnect the spark plug wire.
- Tip the mower safely (air filter and carburetor side up) and clear packed grass from the deck.
- Inspect the blade for bends, cracks, and dull edges.
- Check wheels for side-to-side play and verify retaining hardware is in place.
- Confirm the discharge/bagging path is clear and the deflector moves freely.
| Symptom | Commonly involved part | Example part for this model |
|---|---|---|
| Poor cut, vibration | Blade | Husqvarna lawn mower 21-in deck 3-in-1 blade 532189028 |
| Self-propel not driving | Transmission/drive | Lawn mower transmission assembly 532188294 |
| Poor discharge or bagging | Chute/deflector | Lawn mower clipping deflector 583127101 |
| Wheel wobble | Wheel/bearing/retainers | Wheel 532192622, lawn mower bearing 532187120 |
Catching wear early prevents secondary damage (like a loose blade stressing the crankshaft area or a slipping drive wearing other drivetrain parts). It also restores cut quality and reduces vibration.
For model-specific diagrams, adjustment points, and maintenance intervals, use the Craftsman 917377844 owner’s manual.
Last updated: March 2026





