Craftsman 917378350 rotary lawn mower Parts

On Craftsman rotary lawn mower model 917378350, the serial number is primarily used as an identifier for the exact unit and production run; you’ll find it on a decal on the rear of the mower housing. For the most accurate location and recording instructions, use the 917378350 owner’s manual.

Where to find the serial number on model 917378350

We look for the serial number decal in this spot:

• Rear of the mower housing (back of the deck)
• On a decal that also lists the model number
• Typically near the area you can see when standing behind the mower
• Best read after wiping off grass dust and oil film

How to “read” it (what it tells you)

For this Craftsman walk-behind mower, the manual focuses on where to locate and record the serial number rather than a universal month-day-year decoding rule. Use the serial number to:

• Confirm you’re ordering parts for the correct mower
• Match diagrams and part lists to your exact build
• Track the unit for maintenance records (date of purchase, service notes)

Quick guide: serial number vs. model number

Item	What it’s for	Where you’ll use it most
Model number (917378350)	Identifies the mower design	Parts lookup and diagrams
Serial number	Identifies your specific unit	Verifying exact fit, service records

Tips for recording it correctly

• Write down the full serial number exactly as printed (include any letters)
• Record the date of purchase next to it for your maintenance log
• Take a clear photo of the decal before it fades

Why it matters

Using the correct model number and serial number helps prevent ordering the wrong drive, wheel, or control parts for your Craftsman mower, especially when there are small production changes within the same model family.

Last updated: January 2026

For the Craftsman 917378350 gas walk-behind mower, we recommend using fresh regular unleaded gasoline (typically 87 octane). Using 91 octane usually does not improve performance in small mower engines; fuel freshness and proper storage matter more than higher octane.

What to use (and what to avoid)

• Use fresh, clean unleaded gasoline (87 octane is the normal choice).
• Avoid old or stale fuel; the manual lists stale fuel as a common no-start cause.
• Keep the gas can clean and rust-free; rust or dirt in gasoline can cause problems.
• Do not store gasoline from one season to the next.
• If you suspect bad fuel, drain the tank and refill with fresh gas.

Quick comparison: 87 vs 91 octane

Fuel choice	What it changes in a mower engine	When it makes sense
87 octane (regular)	Normal operation for most walk-behind mowers	Everyday mowing
91 octane (premium)	Usually no added power or reliability benefit	Only if required by the engine manufacturer (rare)

If your mower will not start after refueling

The 917378350 troubleshooting chart points to fuel quality and basic ignition checks first.

• Confirm you have fuel in the tank.
• Replace old fuel with fresh fuel.
• Check the air filter for heavy dirt buildup.
• Make sure the spark plug wire is firmly connected.

For model-specific operating and maintenance details (including fuel handling and storage), follow the 917378350 owner's manual.

Why it matters

Octane mainly affects resistance to knock; most small mower engines are designed to run correctly on regular fuel. What actually prevents hard starting and loss of power is using fresh gasoline and storing it properly between mowing seasons.

Last updated: January 2026

The model number for this Craftsman rotary lawn mower is 917.378350 (often written without the dot as 917378350). You can confirm it in the product documentation for this mower, where it’s listed as the model number for the Craftsman rotary lawn mower. See the 917378350 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 label.

• Check the rear of the deck near the discharge opening or rear door area
• Look on the frame near the height adjuster hardware
• Check around the handle mounting brackets
• Wipe off grass and dirt; the label can be hard to read when dirty

Model number vs. engine model number (common confusion)

This mower uses a Craftsman 4-cycle engine with its own separate engine model number. The engine model number helps with engine-specific parts, but it is not the mower’s model number.

What you’re identifying	Example shown in documentation	What it’s used for
Mower model number	917.378350	Mower deck, wheels, drive system, handle parts
Engine model number	143.026200	Engine parts like carburetor, ignition, recoil starter

Why it matters

Using the correct mower model number (917378350) helps us match the right Craftsman walk-behind mower parts, diagrams, and hardware like the drive system components and handle control parts.

If you’re ordering drive system hardware, the manual parts lists can also help you cross-check items such as the control cable 532168552 and related drive components.

Last updated: January 2026