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What model number is the Craftsman 917377820?
The model number is 917.377820 (often written without the dot as 917377820) for this Craftsman gas walk-behind lawn mower. You can confirm it on the model identification section and parts list in the 917377820 owner's manual.
Where to find the model number on the mower
We typically see the model number on the mower’s ID label, not on the engine itself.
- Check the rear of the deck near the discharge opening
- Look around the handle mounting area (left or right side)
- Inspect near the height-adjuster brackets by the wheels
- Wipe the label clean; grass residue can hide digits
- Record the full number exactly as printed (including any dots)
Model number vs. other numbers you might see
It’s common to find several numbers on a mower. Here is how to separate them:
| Number type | Where it appears | What it’s used for |
|---|---|---|
| Mower model number (917.377820) | Mower ID label | Ordering Craftsman mower parts and using the correct manual |
| Engine model/type/code | Engine shroud or valve cover area | Engine-specific parts (carburetor, ignition, gaskets) |
| Part numbers | On parts diagrams/manual | Identifying individual replacement parts |
Why it matters
Using the exact mower model number ensures we match the correct Craftsman parts diagrams for items like the drive system, handle hardware, and wheel components. For example, the parts list for model 917.377820 includes items such as the lawn mower drive cable 583180101 and related drive hardware.
Last updated: January 2026
Should I use 87 or 91 gas for lawn mower?
For the Craftsman gas walk-behind mower model 917377820, use fresh regular unleaded 87 octane gas for normal mowing. Higher octane (like 91) does not add power or improve reliability in this type of small engine; fuel freshness and clean storage matter far more. For model-specific fueling and safety details, follow the 917377820 owner's manual.
What to use (and what to avoid)
- Use: Fresh, clean 87 octane unleaded gasoline.
- Avoid: Old gas (stale fuel is a common no-start cause).
- Avoid: Gas contaminated with water, rust, or dirt.
- Avoid: Storing fuel in a rusty gas can.
- Do: Keep the fuel cap area clean so debris does not fall into the tank.
Quick comparison: 87 vs 91 for this mower
| Fuel choice | Best use case | What you gain | What matters more |
|---|---|---|---|
| 87 octane (regular) | Everyday mowing | Correct performance for typical mower engines | Freshness, clean can, proper storage |
| 91 octane (premium) | Not needed for normal operation | No practical benefit in most walk-behind mowers | Still goes stale if stored too long |
If the mower will not start after fueling
Stale or contaminated fuel is a frequent culprit. If your 917377820 cranks but will not fire, focus on fuel quality first.
- Drain or run out old fuel and refill with fresh gas
- Check the air filter and clean or replace if dirty
- Verify the spark plug wire is firmly connected
- Make sure the operator presence control bar is held down while starting
- If fuel has been sitting, inspect the can for rust or debris
For step-by-step guidance, use the troubleshooting section in the 917377820 owner's manual.
Why it matters
Using the right fuel is less about octane and more about preventing varnish, corrosion, and starting problems. Fresh 87 octane gas stored in a clean container helps protect the carburetor and keeps starting consistent.
Last updated: January 2026
What year is my Craftsman mower serial number lookup?
For a Craftsman walk-behind mower like model 917377820, the serial number format does not reliably encode the build year the way some online “MMDDYY” examples suggest. The most accurate way to identify the year is to match your mower’s serial and product labels to the identification guidance in the 917377820 owner's manual.
How to find the serial number and ID labels
On most Craftsman walk-behind mowers, the model and serial information is printed on a label attached to the mower housing or frame.
- Look on top of the deck near the engine mounting area
- Check the rear of the deck near the bagger door or discharge opening
- Inspect the handle bracket area for a sticker or metal tag
- Wipe dirt and grass residue off the label so every character is readable
- Write down the full model number and the full serial number (do not shorten)
What to use for a “year lookup” (best to least reliable)
Because serial formats vary by manufacturer and production run, we use a label-based approach first.
| Method | What you need | Reliability |
|---|---|---|
| Manual label identification | Model and serial from the mower tag | High |
| Parts diagram match | Your mower’s assemblies match the diagrams | Medium |
| “First digits are date” rules from videos/forums | Serial number only | Low |
Quick cross-check using parts diagrams (practical tip)
If you are trying to confirm you have the correct product family, compare a few visible assemblies to the diagrams for model 917377820.
- Drive system parts (belt, pulleys, gear case) match the diagram layout
- Handle and control bar style matches the handle breakdown
- Rear door/bagger door style matches the listed door component
- Wheel and dust cover style matches the drive wheel setup
If you are replacing worn drive components while you are identifying the mower, common items on this model include the lawn mower drive cable 583180101 and the lawn mower zone control cable 532191221.
Why it matters
The correct year and production run affects parts fit. Small changes in the drive control assembly, gear case, wheels, and handle hardware can change which Craftsman parts (and part numbers) are compatible with your mower.
Last updated: January 2026
