Does it matter what gas I put in my lawn mower?
Yes. For your Craftsman walk-behind mower model 917388100, using the right gasoline helps prevent hard starting, rough running, and fuel-system problems. Use fresh, clean regular unleaded gasoline (most owners use E10); avoid old fuel and keep water and dirt out of the gas can. See the 917388100 owner's manual for fueling and storage guidance.
What we recommend for fuel
- Use fresh regular unleaded gasoline from a clean container.
- E10 (up to 10% ethanol) is commonly used in walk-behind mowers; do not use higher-ethanol blends.
- Buy only what you will use in 30 days (or treat it with stabilizer if storing longer).
- Keep the cap tight and store fuel where it will not absorb moisture.
- If the mower has been sitting, drain/replace old fuel before troubleshooting.
Quick fuel troubleshooting (when it will not start)
Stale or contaminated fuel is a top cause of no-start. The 917388100 troubleshooting chart also points to fuel and ignition basics.
- Confirm you are not out of fuel.
- Replace stale fuel (old gas) with fresh fuel.
- If you suspect water in fuel, drain the tank and refill.
- Check the air filter and spark plug wire connection.
- Inspect for a loose blade or damaged blade adapter, which can affect starting and operation.
If you are also dealing with starting issues, follow the steps in lawn mower wont start troubleshooting video fuel ignition and compression.
Fuel choices at a glance
| Fuel choice | OK to use? | Why |
|---|---|---|
| Fresh regular unleaded | Yes | Reliable starting and normal performance |
| E10 (10% ethanol) | Yes (typical) | Common pump fuel; use fresh and store properly |
| Higher-ethanol blends (E15/E85) | No | Can cause fuel-system and running problems |
| Old gas (last season) | No | Leads to hard starting, surging, and varnish buildup |
Why it matters
Fuel quality directly affects the carburetor and starting system. The manual also warns not to store gasoline from one season to the next and to replace rusty gas cans because rust and dirt in fuel cause problems.
Last updated: January 2026
What model number is the Craftsman 917388100?
The model number for this Craftsman walk-behind gas lawn mower is 917.388100 (often written without the dot as 917388100). You’ll see it printed on the mower’s model label and on the cover page of the 917388100 owner's manual.
Where to find the model number on the mower
Most Craftsman walk-behind mowers place the model label in an easy-to-spot area on the deck or rear housing.
- Check the rear of the mower deck near the bagger door area
- Look along the side of the deck near the discharge chute
- Wipe off grass and dirt; the label can be hard to read when dirty
- Write the number exactly as shown (including dots or dashes)
Model number vs. engine model number (common mix-up)
Your mower model number identifies the Craftsman mower assembly; the engine has its own separate model number.
| What you’re identifying | Example you may see | What it’s used for |
|---|---|---|
| Mower model number | 917.388100 (917388100) | Finding Craftsman chassis parts like the handle, wheels, blade, and cables |
| Engine model number | 122T02-0824-EA | Finding Briggs & Stratton engine parts like carburetor and ignition components |
Why it matters
Using the correct mower model number helps us match the right walk-behind mower parts (blade, blade adapter, zone control cable, wheels) so fit and mounting holes line up correctly.
Last updated: January 2026
What's the average lifespan of a lawn mower?
Most gas walk-behind lawn mowers last 8 to 15 years with normal homeowner use and consistent maintenance. For the Craftsman 917388100, routine oil changes, keeping the blade sharp, and cleaning built-up grass from the deck are the biggest factors that extend service life.
What most affects mower lifespan
A mower usually wears out from neglected maintenance, overheating, or impact damage more than from “age.” Focus on these items:
- Change engine oil on schedule (this model uses 20 oz; oil type varies by temperature).
- Keep the underside of the deck clean after each use to prevent corrosion and drag.
- Keep the blade sharp; replace bent or damaged blades.
- Keep the engine exterior clear of debris so it runs cooler.
- Avoid water intrusion; don’t wash the mower with a hose unless sensitive areas are protected.
Maintenance checkpoints (quick guide)
Use this as a simple baseline; the exact intervals and procedures are in the 917388100 owner's manual.
| Item | What to do | Why it helps lifespan |
|---|---|---|
| Engine oil | Use SAE 30 above 32°F; SAE 5W-30 below 32°F | Reduces internal wear |
| Blade | Sharpen or replace as needed | Prevents vibration and poor cut |
| Deck underside | Scrape off grass buildup after mowing | Reduces rust and load on engine |
| Spark plug | Replace about every 100 hours (type listed in manual) | Improves starting and running |
Why it matters
A mower that runs hot, vibrates, or has heavy grass buildup works harder every time you mow. That extra load shortens engine life and can accelerate wear on parts like the blade adapter and wheels.
Parts that commonly wear during normal use
These are considered normal wear items on many mowers, including the 917388100:
- Blade
- Blade adapter
- Air filter
- Spark plug
- Drive and control cables
If you’re replacing a damaged cutting component, match the correct OEM-style part for this model, such as the lawn mower blade 532406712 when applicable.
Last updated: January 2026





