How much does it cost to replace a riding lawn mower engine?
For a Craftsman riding lawn tractor like model 917272450, a full engine replacement typically costs about $800 to $2,500+ installed (engine plus labor). The engine itself is usually the biggest cost; labor commonly runs 3 to 6 hours depending on how much has to be transferred from the old engine.
What drives the total cost
- Engine type and horsepower (single-cylinder vs. V-twin)
- Crankshaft size and PTO setup (must match your mower deck drive)
- What gets reused (starter, charging system, muffler, pulleys, wiring)
- Extra repairs found during the swap (belts, pulleys, battery cables)
- Shop labor rate and pickup/delivery fees
Typical price ranges (parts + labor)
| Scenario | What you’re paying for | Typical total |
|---|---|---|
| Budget replacement | Basic compatible engine, minimal transfer work | $800 to $1,500 |
| Most common | Correct-spec engine, normal transfer and setup | $1,200 to $2,200 |
| Higher-end or complicated | Premium engine, lots of transfer work, extra worn parts | $2,000 to $2,500+ |
When replacement makes sense (and when it doesn’t)
Replacing the engine is usually worth it when the tractor is in good shape overall (deck, steering, transaxle, wiring). If multiple major systems are worn, repairs can stack up quickly.
Quick checks we recommend before committing:
- Confirm the engine is truly failed (not a battery, solenoid, or safety interlock issue).
- Check for common “no crank” causes like a weak battery or bad starter circuit.
- Review the starting and safety interlock behavior described in the owner's manual.
Lower-cost alternatives to consider first
If the engine still turns over, a tune-up or fuel/ignition fix can be far cheaper than an engine swap.
- Fuel system cleanup (fresh fuel, filter, carburetor service)
- Spark plug and ignition checks
- Air filter and oil service
- Electrical starting diagnosis (clicking, no crank)
A good starting point for diagnosis is our riding lawn mower engine clicks but doesnt turn over video.
Why it matters
An engine swap is one of the most expensive repairs on a riding mower. Verifying the failure first helps you avoid replacing an engine when the real issue is a safety switch, wiring connection, or starting component.
Last updated: February 2026
Is it worth replacing a lawn mower engine?
Replacing the engine on your Craftsman lawn tractor model 917272450 is worth it when the tractor is otherwise solid (deck, steering, transaxle, and frame are in good shape) and the total engine-swap cost stays well below the cost of a comparable replacement tractor. If multiple major systems are worn, the money is usually better spent elsewhere.
Quick decision checklist
- Deck and blades are serviceable: no major cracks, and the cutting system can be maintained (the manual emphasizes keeping blades and attachments tight and in good condition). See the 917272450 owner's manual.
- No chronic overheating issues: the manual notes blocked cooling fins or missing shrouds can cause engine damage; if the tractor has been run hot repeatedly, inspect carefully.
- You can still get key wear parts: blades, mandrel parts, and hardware are available for this model.
- The rest of the tractor drives and stops correctly: the manual calls out checking brake operation frequently; if braking or drive is failing, factor that cost in.
- You want to keep this platform: same deck size, attachments, and familiar controls.
Cost and value: a practical rule
Use this simple comparison to decide:
| What you’re comparing | Good candidate for engine replacement | Better to replace the tractor |
|---|---|---|
| Total repair cost (engine + labor + incidentals) | Under ~50% of a comparable replacement | Near or over ~50% |
| Condition of deck and spindles/mandrels | Tight, quiet, no wobble | Noisy, loose, repeated failures |
| Overall tractor condition | Solid chassis, steering, brakes | Multiple major issues at once |
Parts that often get addressed during an engine swap
Even if the engine is the main issue, we often see these items handled at the same time to protect your investment:
- Blade and spindle/mandrel wear: a worn mandrel can cause vibration and poor cut; consider the husqvarna lawn tractor mandrel assembly 532130794 if your deck spindle is failing.
- Blade condition: a sharp, correct blade reduces strain; the husqvarna lawn tractor mulching blade, 21-in 532134149 is one option listed for this model’s parts.
- Starter electrical issues: if you only get a click/no crank, the solenoid with brass plunger 532146154 is a common fix path.
Why it matters
A new engine only pays off if the tractor can safely mow afterward. The manual stresses safe maintenance practices (no repairs with the engine running, keep debris cleared, and inspect after striking objects), which helps prevent repeat failures and protects the deck and drivetrain.
Last updated: February 2026
What kind of engine does a Craftsman riding lawn mower have?
Craftsman lawn tractor model 917272450 is equipped with a 21.5 HP low-emission gasoline engine (as specified in the 917272450 owner's manual). For the exact engine make and engine model number used on your tractor, use the engine ID label under the hood.
What we know for model 917272450
These model-specific specs are called out in the owner’s manual:
- 21.5 HP engine rating
- Low-emission engine design
- Electric start
- 42-inch mower deck
- 6-speed transaxle
How to identify the exact engine make and model
On Craftsman tractors, the tractor model number and the engine model number are different. To identify the engine correctly:
- Raise the hood and locate the engine ID label (commonly on the blower housing, valve cover, or near the starter)
- Record the engine model, type, and code (or spec number)
- Use those numbers when selecting engine tune-up parts like the air filter, spark plug, and fuel filter
- Keep the tractor model 917272450 for deck, steering, chassis, and electrical parts
Quick reference: tractor model vs. engine model
| Number you have | What it identifies | Used for ordering |
|---|---|---|
| 917272450 | The tractor platform | Deck, steering, frame, wiring, transmission-related parts |
| Engine model/type/code | The engine itself | Engine maintenance and engine-specific service parts |
Why it matters
Many Craftsman tractors in this size class use engines that share horsepower but differ in carburetor, ignition, and filter designs. Using the engine ID label prevents ordering the wrong tune-up parts even when the tractor model is correct.
Last updated: February 2026





