Should I use 87 or 91 gas for lawn mower?
For the Craftsman 917377841 gas walk-behind lawn mower, we use regular unleaded 87-octane gas for normal mowing. Higher octane (like 91) does not add power or improve performance in a mower engine; the key is using clean, fresh fuel and storing it correctly (see the owner's manual).
What to use (and what to avoid)
- Use: Fresh, regular unleaded 87 octane
- Avoid: Old or contaminated gas (it causes hard starting and rough running)
- Avoid: Storing gas from one season to the next in your can or mower
- Do: Replace a rusty gas can; rust and dirt in fuel create carburetor problems
- Do: Keep gasoline off wheels and finished surfaces when refueling
Why 91 octane usually is not worth it
Octane is mainly about preventing knock in high-compression engines. Most walk-behind mower engines are designed to run correctly on regular fuel, so paying for premium typically brings no benefit.
Quick comparison
| Fuel choice | What you get | Best use case |
|---|---|---|
| 87 octane (regular) | Correct performance for typical mower engines | Everyday mowing |
| 91 octane (premium) | Higher knock resistance, not more power | Only if your engine specifically calls for it |
Fuel freshness and storage tips (what matters most)
Stale fuel is one of the most common reasons a mower will not start. For best results:
- Buy only the amount of gas you will use in about 30 days
- Store fuel in a clean, approved gas can
- If you are storing the mower, run it until the tank is empty (or treat fuel per your routine)
- Never store the mower indoors with gas in the tank where fumes could reach a flame or spark
Why it matters
Using the right fuel helps prevent hard starting, surging, and carburetor varnish, which reduces downtime and extends engine life. Good fuel habits also support easier seasonal maintenance like spark plug replacement and tune-ups.
You can also order common replacement items and hardware for this model (for example, the lawn mower e-ring 812000058) from the parts list for Craftsman 917377841, or search by model number on Sears PartsDirect.
Last updated: February 2026
What model number is the Craftsman 917377841?
The model number is 917.377841; it identifies your specific Craftsman gas walk-behind lawn mower for ordering the correct parts and matching the right diagrams. You’ll see it printed in the parts breakdown in the owner's manual.
Where to find the model number on the mower
Check these common locations on Craftsman walk-behind mowers like model 917.377841:
- On the rear of the deck near the discharge opening
- On the deck top surface near the engine mounting area
- On a label near the handle mounting brackets
- In the parts list and exploded-view diagrams in the owner's manual
Why the model number matters when buying parts
Many parts look similar across Craftsman mowers, but fit and hardware sizes can differ. Using 917.377841 helps us match the correct items such as:
- Drive and wheel hardware (washers, lock nuts, retaining rings)
- Grass bag and chute components
- Drive control and gear case parts
- Handle and control parts
Quick check: model number vs. engine model
Your mower model number and engine model number are different identifiers.
| Identifier type | Example for this mower | What it’s used for |
|---|---|---|
| Mower model number | 917.377841 | Deck, drive system, handle, bag, chute, wheels |
| Engine model number | Honda GCV190-AS3A | Engine-specific tune-up and engine parts |
Ordering the right parts
We recommend using the mower model number first when selecting parts for the deck and drive system. For example, common hardware and assemblies listed for this model include items like the lawn mower grass bag 532410670 and lawn mower clipping deflector 583127101. You can also search by model number on Sears PartsDirect.
Why it matters
Using the exact model number prevents wrong-part returns and helps ensure safe operation, especially for drive components, blade-related hardware, and discharge parts.
Last updated: February 2026
What year is Craftsman Model 917377841?
Craftsman model 917377841 identifies the mower design and parts breakdown, but it does not provide a single “model year.” To determine the year your specific mower was built, use the date or serial information on the product ID label and cross-check details in the 917377841 owner's manual.
How to find the build date on the mower
Look for the product identification label (sometimes called the model/serial tag). Common locations on a Craftsman gas walk-behind mower include:
- Rear of the mower deck near the discharge area
- Top of the deck behind the engine
- Near the handle mounting brackets
- Near the drive control or gearcase area
What to record from the label
Write down every field exactly as shown; the year is typically derived from the serial/date code on the tag.
- Serial number (often contains a date code)
- Date of manufacture (DOM) if listed
- Product number or ID number (if separate from the model)
- Any stamped date on the deck or tag
Model number vs. serial number (what each tells you)
| Identifier | What it tells you | What to use it for |
|---|---|---|
| Model number (917377841) | Which diagrams and parts list apply | Ordering correct mower parts |
| Serial/ID label | When your specific unit was produced | Determining build year |
| Engine model/type | Which engine service parts fit | Tune-up and engine parts matching |
Why we do not use the model number to date it
On this Craftsman platform, the model number is a catalog identifier for parts and diagrams, not a date code. The reliable way to identify the year is the mower’s ID label information.
Ordering parts while you confirm the year
You can order parts by model number from the parts list for 917377841, and you can also search by model on Sears PartsDirect. If you are servicing the drive system, examples of model-matched parts include the lawn mower idler pulley 532166043 and the lawn mower selector spring 532188508.
Why it matters
Knowing the build year helps avoid mismatches when there are mid-production changes to drive control parts, wheels, handle hardware, or deck components.
Last updated: February 2026
What are the common problems with Craftsman lawn mowers?
Common problems on the Craftsman 917377841 gas walk-behind lawn mower are the same issues covered in its troubleshooting chart: loss of power, poor or uneven cut, excessive vibration, and a starter rope that’s hard to pull. We use the 917377841 owner's manual to match each symptom to the most likely cause and fix.
Common symptoms and what usually causes them
- Loss of power: cutting too much grass, grass and debris buildup under the mower housing, dirty air filter, oil level issues, walking speed too fast
- Poor or uneven cut: worn, bent, or loose blade; uneven wheel height settings; deck packed with clippings
- Excessive vibration: worn, bent, or loose blade; blade adapter problems; bent crankshaft (after impact)
- Starter rope hard to pull: blade dragging in grass, deck buildup, flywheel brake engaged when the control bar is released
- Self-propelled drive issues (common on many Craftsman walk-behind mowers): debris binding the rear drive wheels and dust cover area
Quick checks we recommend (safe and fast)
- Disconnect the spark plug wire before working near the blade or under the deck.
- Raise the cutting height if the mower bogs down in tall or wet grass.
- Clean the underside of the mower housing to restore airflow and blade lift.
- Check the air filter and replace it if it’s dirty.
- Verify wheel heights are set evenly on both sides.
Symptom-to-fix guide
| Symptom | Most likely cause | What to do first |
|---|---|---|
| Loss of power | Deck buildup, dirty air filter | Clean underside; service air filter |
| Poor cut | Blade condition, wheel height mismatch | Inspect blade; set wheel heights evenly |
| Excessive vibration | Bent/loose blade or adapter | Tighten hardware; replace damaged parts |
| Rope hard to pull | Blade dragging, brake engaged | Raise height; check control bar operation |
Why it matters
Correcting deck, blade, and airflow problems early improves cut quality and reduces strain on the engine and drive system.
If you need replacement hardware while servicing the deck or controls, model-matched items like the lawn mower idler pulley 532166043 and lawn mower handle knob 583106401 are available from the parts list for this mower, or you can search by model number on Sears PartsDirect.
Last updated: February 2026





