How to identify a lawn mower engine?
To identify the engine on your Craftsman rear-engine riding mower model 107280340, locate the engine’s ID label or stamping on the engine shroud (sheet metal) near the muffler and air cleaner; that model/type code is what you use to match service parts and specs. See the 107280340 owner's manual.
Common places the engine model and type are shown include:
- On the sheet metal shroud directly above or near the muffler (either side)
- On the front of the engine shroud near the air cleaner housing
- On a label near the recoil starter area or blower housing
- Near the spark plug area (sometimes on a tag or stamped pad)
- On the valve cover area (less common, but possible)
Engine identification usually includes a few fields. Write them down exactly as shown.
| What you’ll see | What it’s used for | Example (format) |
|---|---|---|
| Model / type code | Correct tune-up and maintenance parts | XXXXX-XXXX-XX |
| Code / date | Helps identify production version | YYMMDD or similar |
| Spec number (sometimes) | Confirms exact configuration | Spec-XXXX |
The mower model number 107280340 identifies the tractor and deck; the engine model/type identifies the exact engine build. That difference matters when you’re choosing items like the air filter, spark plug, fuel system parts, or ignition components.
Follow these basic precautions before reaching around the engine:
- Stop the engine and let hot parts cool (muffler and exhaust can burn)
- Disconnect the negative (black) battery cable before service
- Remove the spark plug wire and secure it away from the plug
- Keep hands clear of the blade area; blades are sharp
Last updated: January 2026
How old is my mower by serial number?
For a Craftsman rear-engine riding mower model 107280340, the serial number can sometimes indicate the build date, but the format varies by manufacturer and engine. We recommend using the identification label on the mower plus the date and spec details in the 107280340 owner's manual to narrow the manufacturing timeframe.
On most rear-engine riders, the ID label is commonly found in one of these places:
- Under the seat pan or seat bracket area
- On the rear frame near the transaxle
- On the mower deck shell (top surface) or deck hanger area
- Near the engine mounting plate
- On the frame rail by the left or right rear wheel
Also write down these items because they help confirm age and correct parts:
- Model number: 107280340
- Engine brand and model (often Briggs & Stratton on this unit)
- Engine code/date (if present on the engine shroud or valve cover area)
- Any product number or type code listed with the serial
Many mower serial formats include a date code, but it is not universal. Common patterns we see:
- YYMMDD (year, month, day)
- MMDDYY (month, day, year)
- YYWW (year and production week)
- A letter prefix plus digits (letter indicates plant or series, digits include date)
| Example pattern | What it means | Example result |
|---|---|---|
| YYMMDD | 2-digit year, month, day | 210615 = June 15, 2021 |
| YYWW | year + week number | 1934 = week 34 of 2019 |
If you have multiple mowers or swapped engines, confirm you are working from the correct unit. The 107280340 operator manual lists key identifiers such as a 28-inch deck and 12.5 HP Briggs & Stratton engine (344 cc), which helps match the correct equipment to the serial tag.
Knowing the build timeframe helps us match the right maintenance parts and service procedures (blade, deck belt, air filter, spark plug) and prevents ordering parts for a similar-looking but different production run.
Last updated: January 2026
How to read Craftsman model number?
Craftsman model numbers like 107280340 identify the product family and configuration, not the build date. For your Craftsman 107280340 rear-engine riding mower, use the model and serial information on the ID tag (rear frame, between the wheels) when ordering parts or getting service; see the 107280340 operator's manual.
We use these identifiers to match the correct diagrams, parts, and specifications for your riding mower.
- Model number: 107280340 (used to find the correct parts list)
- Unit serial number: used to narrow production variations
- Engine numbers (maker, model, type/spec, code/serial): used for engine-specific parts
- Stock number (if listed): sometimes used for cross-referencing
The ID tag is the most reliable source because it ties directly to your exact machine.
| Field on tag | What it tells us | When you need it |
|---|---|---|
| Model name/number | The mower platform and deck configuration | Always (parts lookup) |
| Unit serial number | Production run details | When parts vary by serial range |
| Engine model/type/spec | Exact engine configuration | Spark plug, air filter, carburetor, starter parts |
| Engine code/serial | Engine build identifiers | Engine service and parts matching |
Many Craftsman outdoor power products do not encode a simple manufacture date in the model number. The model number is primarily a product identifier; the serial number and engine code are what typically help date or version the unit.
Using the correct model and serial information prevents ordering the wrong mower deck, drive components, belts, blades, or engine parts, and it speeds up troubleshooting and service.
Last updated: January 2026
Is it worth replacing a lawn mower engine?
Yes, replacing the engine on your Craftsman 107280340 rear-engine riding mower is worth it when the tractor chassis, deck, and transmission are still solid and you want to extend the mower’s life; it is usually the right call when the engine is the only major failure and the replacement cost stays well below the cost of a comparable new rider.
- Deck and frame are sound: no major rust-through, cracks, or bent deck shell.
- Transmission drives normally: it moves forward and reverse without slipping (your model uses a 5-speed disc drive).
- Cut quality issues are fixable: uneven or rough cut is often blade, belt, leveling, or tire pressure related.
- You can match key engine specs: crankshaft size, mounting pattern, and charging output.
- You want to keep the same mower size: this model is a 28-inch deck rider, which can be hard to replace at the same footprint.
Your Craftsman 107280340 is a compact rear-engine rider with a 28-inch deck, 12.5 HP / 344 cc engine, and a listed weight of 314 lb. If the mower still steers well, brakes hold, and the deck engages properly, an engine swap can be a practical way to keep a known-good machine running. See the specs section in the 107280340 owner's manual.
| Option | Best when | Typical downside |
|---|---|---|
| Replace engine | Deck, drive, and controls are in good shape | Upfront cost and install time |
| Repair existing engine | Problem is minor (carb, ignition, fuel) | May not solve low compression or internal wear |
| Replace mower | Multiple major systems are worn | Higher total cost, new setup and accessories |
On a riding mower, the engine is only one part of the total system. If the deck belt, blades, steering, and drive are healthy, replacing the engine restores reliability without starting over with a different machine.
- Disconnect the negative (black) battery cable before service.
- Remove and secure the spark plug wire away from the plug.
- Work only with the engine stopped and the mower blocked safely.
- Avoid overspeeding; do not change governor settings.
Last updated: January 2026





