What are the parts of a lawn mower engine?
On the Craftsman front-engine lawn tractor model 9172559101, the engine system is made up of fuel, air, ignition, and mechanical components that work together to create combustion and deliver power to the drivetrain and mower deck. Common engine-related parts include the fuel tank, air filter, carburetor, ignition parts, and internal rotating assemblies.
Core engine parts (what they do)
- Fuel tank: stores gasoline and feeds the fuel system (see fuel tank 532151346).
- Carburetor: mixes fuel and air in the correct ratio for starting and running.
- Air filter: keeps dirt out of the engine so it does not wear out quickly.
- Ignition system: typically includes the ignition coil and spark plug; creates spark to ignite the fuel mixture.
- Flywheel: helps smooth engine rotation; often contains magnets used for ignition charging.
- Crankcase and crankshaft: houses oil and supports the rotating crankshaft.
- Starter system: on many riding tractors this is an electric starter motor and solenoid (push-button or key start).
Engine-related parts you may see listed separately on a tractor
A riding mower like the Craftsman 9172559101 also uses safety and control parts that affect whether the engine can start and keep running:
- Lawn tractor ignition switch 532365402
- Lawn tractor seat switch 532421062
- Battery cables, fuses, and interlock wiring (varies by configuration)
Quick “engine vs. tractor” parts comparison
| System | Examples | What you notice when it fails |
|---|---|---|
| Fuel and air | fuel tank, carburetor, air filter | hard starting, surging, stalls under load |
| Ignition | spark plug, ignition coil, flywheel | no-start, misfire, backfiring |
| Starting and safety | ignition switch, seat switch | no crank, crank but no start, dies when you get off seat |
Why it matters
Knowing which system you are dealing with helps you troubleshoot faster. For example, a no-start can be fuel-related (old gas, clogged carburetor) or safety-related (seat switch or ignition switch not closing the circuit).
Helpful DIY guidance
If you are diagnosing a start or no-start issue, use riding lawn mower engine spins but wont start video or riding lawn mower engine wont turn over or click video to narrow it down by symptoms.
Last updated: February 2026
What engine does Craftsman riding mower use?
For the Craftsman riding mower model 9172559101, the exact engine make and model varies by the tractor’s original build configuration; most Craftsman front-engine lawn tractors in this class use a single-cylinder gasoline engine in the mid-HP range. For engine-specific parts, we match by the tractor model and the engine’s ID tag.
How to identify the exact engine on model 9172559101
Use the engine identification label (usually on the blower housing, valve cover area, or near the starter) and record:
- Engine brand (commonly Briggs & Stratton, Kohler, or Tecumseh on older units)
- Model number
- Type (or spec) number
- Code (date code)
- Any emissions family information (if shown)
What we can confirm from parts selection on this model page
Even when the engine brand differs, the tractor model number 9172559101 is the key for many chassis and electrical items that affect starting and running.
- If the key won’t crank the engine, check the lawn tractor ignition switch 532365402
- If it cranks only when you shift in the seat, inspect the lawn tractor seat switch 532421062
- If you are chasing a no-start caused by fuel delivery, inspect the tank and lines; the fuel tank 532151346 is a common replacement item
Quick symptom-to-system guide
| Symptom | Most likely system | What to check first |
|---|---|---|
| Clicks but won’t crank | Battery, cables, solenoid, safety switches | Seat switch, brake switch, battery connections |
| Cranks but won’t start | Fuel, spark, air | Fresh fuel, spark plug, air filter |
| Starts then dies when brake released | Safety interlock circuit | Brake switch, seat switch wiring |
Why it matters
Ordering the correct engine parts (carburetor, starter, ignition coil, air filter) requires the engine model/type/code, while many tractor parts (switches, belts, deck hardware) match directly to Craftsman 9172559101.
Helpful DIY video guides
- Riding lawn mower engine spins but wont start video
- Riding lawn mower engine clicks but doesnt turn over video
- Riding lawn mower engine dies when you release the brake video
Last updated: February 2026
What model number is the Craftsman 42 riding mower?
For the Craftsman front-engine lawn tractor on this page, the model number is 9172559101. If you are asking about a different Craftsman 42-inch riding mower, the model number is found on the tractor’s model and serial number label, not just by deck size.
Where to find the model number on a Craftsman riding mower
On most Craftsman riding mowers and lawn tractors, the model label is easy to spot once you know where to look.
- Under the seat (seat pan area)
- On the rear fender or frame near the seat
- On the left or right side of the frame, below the hood
- Near the engine compartment on the frame rail
- On the mower deck housing (less common for the main tractor model)
Why “42-inch” is not enough
“42-inch” describes the cutting deck width, but Craftsman used that deck size across many tractor series and years. Two 42-inch tractors can use different belts, pulleys, switches, and fuel system parts.
Quick comparison
| What you have | What it tells us | What we still need |
|---|---|---|
| 42-inch deck | Deck size only | Exact model number (for correct parts) |
| Model number 9172559101 | Exact tractor identity | Serial number (helpful for production changes) |
Parts that commonly depend on the exact model number
Once you confirm the model number, you can match the correct replacement parts for your Craftsman tractor, such as:
- Ignition switch (no-crank or intermittent start issues) like the lawn tractor ignition switch 532365402
- Safety interlock components like the lawn tractor seat switch 532421062
- Drive and deck belts (ground drive belt vs blade drive belt)
- Fuel system parts (tank, lines, caps)
- Deck and spindle hardware
Why it matters
Using the correct model number (for example, 9172559101) prevents ordering the wrong belt length, switch style, or mounting pattern, which saves time and avoids repeat repairs.
Last updated: February 2026
What year is Craftsman Model 9172559101?
Craftsman model 9172559101 does not have a single built-in “model year”; the year is identified from the tractor’s product identification/date code on the unit (not from the 917-prefix model number itself). We use that date code to determine the exact build date and year.
Where to find the date code on a 917-series Craftsman tractor
Look for a product ID label on the tractor frame, typically:
- Under the seat pan or on the seat deck
- On the rear fender area near the seat
- On the frame rail near the engine
- Near the transaxle area on the rear frame
If the label is dirty or faded, wipe it clean and use a flashlight; a phone photo often makes the characters easier to read.
How to decode the date (common format)
Many Craftsman 917-series tractors use a 6-digit date code that reads as:
- MM = month
- DD = day
- YY = year
Example
| Date code | Decodes to | Year |
|---|---|---|
| 072811 | July 28, 2011 | 2011 |
| 031507 | March 15, 2007 | 2007 |
Why it matters
Knowing the build year helps us match the correct Craftsman parts and specs for your tractor, especially for items that change over production runs (belts, switches, wheels, and fuel system parts).
Parts that commonly depend on the exact build date
When you are confirming fit, we often see date-related differences in:
- Ground drive belt routing and length (example part: lawn tractor ground drive belt 532110883)
- Deck belt length and pulley setup (example part: lawn tractor blade drive belt 532110884)
- Safety interlock components (example part: lawn tractor seat switch 532421062)
- Starting circuit components (example part: lawn tractor ignition switch 532365402)
Helpful DIY reference
If your tractor is also having starting issues while you are checking the ID label, use: riding mower and tractor common questions.
Last updated: February 2026





