How much does it cost to replace a riding lawn mower engine?
For a Craftsman lawn tractor like model 917270773, a full engine replacement typically costs $260 to $1,800 installed, depending on the engine type, labor rates, and whether related items (belts, pulleys, wiring) also need service. Plan on roughly 6 hours of labor for many riding mower engine swaps.
- Engine cost: new replacement engines vary widely by horsepower, shaft size, and brand compatibility.
- Labor time: removing the hood, wiring, throttle/choke cables, fuel line, exhaust, and mounting bolts adds time.
- Extra parts: worn drive components, mounting hardware, or electrical parts can add cost.
- Shop rates: local labor rates and minimum charges vary.
- Condition of the tractor: rusted fasteners, damaged wiring, or fuel contamination increases labor.
| Cost item | Typical range | Notes |
|---|---|---|
| Replacement engine (part only) | $200 to $1,400 | Biggest variable; must match crankshaft specs |
| Labor | $200 to $600 | Often 4 to 8 hours depending on complexity |
| Misc. supplies and small parts | $20 to $150 | Fuel line, clamps, oil, filter, hardware |
Many “needs an engine” symptoms are actually tune-up or safety-interlock issues. The 917270773 manual highlights items like dirty air filter, stale fuel, spark plug problems, wiring issues, and operator-safety presence control problems.
- Drain old fuel and refill with fresh gasoline
- Replace or clean the air filter
- Inspect and replace the spark plug if fouled
- Check battery cables and wiring connections
- Verify the operator presence and interlock system works as described in the 917270773 owner's manual
An engine swap is one of the highest-cost repairs on a riding mower. Confirming fuel, ignition, and safety interlock operation first helps avoid replacing an engine when a lower-cost fix restores starting and power.
Last updated: January 2026
Who makes the Craftsman 420cc engine?
For the Craftsman 917270773 lawn tractor, the owner’s manual identifies the tractor as a 19.0 HP model but does not list a 420cc engine manufacturer. In general, many Craftsman-branded 420cc single-cylinder engines used on riding equipment are produced by MTD (often sold under the Powermore name) depending on the specific tractor and engine model.
Use the engine’s ID tag, not the hood badge. The engine maker is tied to the engine model and type code.
- Locate the engine ID label (usually on the blower housing, valve cover area, or near the starter)
- Write down the engine model, type, and code (or serial number)
- Match that information to the engine parts list and service info in the 917270773 owner’s manual
- If the label is missing, check for stamped numbers on the engine shroud or valve cover
- Compare the engine’s air filter housing and carburetor layout to common MTD, Briggs and Stratton, and Kohler designs
The manual for Craftsman model 917270773 focuses on tractor specs and maintenance, including fuel, oil, and tune-up basics.
| Spec item | What to look for | Why it helps |
|---|---|---|
| Engine rating | 19.0 HP (tractor spec) | Confirms the tractor configuration |
| Fuel type | Unleaded regular | Helps avoid starting and running issues |
| Oil type | SAE 30 above 32°F; SAE 5W-30 below 32°F | Helps protect the engine and improve cold starts |
Ordering the right ignition parts, air filter, carburetor parts, and tune-up items depends on the engine model, not just the tractor model number. Confirming the engine maker first prevents wrong-part returns and no-start problems.
Last updated: January 2026
What engine does Craftsman riding mower use?
The Craftsman lawn tractor model 917270773 is specified as a 19.0 HP riding lawn tractor with electric start and a 42-inch mower deck. For the exact engine make and model (as listed for your tractor), use the engine identification section in the 917270773 owner's manual.
Use these quick checks to match the engine correctly before ordering tune-up parts:
- Look for the engine ID label on the blower housing, valve cover, or near the starter
- Record the engine model, type, and code (common on Briggs & Stratton engines)
- Match the label info to the manual’s engine/maintenance section
- Confirm spark plug type and gap before buying (the manual lists Champion RJ19LM / J19LM, gap .030 in.)
- Verify oil type by temperature (SAE 30 above 32°F; SAE 5W-30 below 32°F)
These specs from the manual help validate you are working with the correct Craftsman tractor configuration.
| Spec | 917270773 value |
|---|---|
| Horsepower | 19.0 HP |
| Starting system | Electric start |
| Mower deck | 42 in |
| Fuel capacity | 3.5 gallons |
| Battery | U1R, 30 Ah, 240 CCA |
The engine make and model determines the correct maintenance parts (spark plug, air filter, fuel filter) and service specs. Using the tractor model number alone can lead to the wrong engine parts if the engine family varies by production run.
Last updated: January 2026
Is it worth replacing a lawn mower engine?
Replacing the engine on your Craftsman lawn tractor model 917270773 is worth it when the deck, steering, and drive system are still solid and the total swap cost stays under about half the price of a comparable new rider. If multiple systems are worn, replacement makes more sense.
Use these checkpoints before buying an engine:
- Frame and deck are not cracked or heavily rusted
- Transaxle drives smoothly and does not slip or leak heavily
- Deck spindles, pulleys, and belts are serviceable
- Total cost (engine + parts + labor) stays under about 50% of a new rider
- You can handle fuel, wiring, throttle/choke linkages, and mounting work
| Option | Typical cost range | Best when |
|---|---|---|
| Tune-up/repair | $50 to $300 | Starting or running issue, engine still healthy |
| Short block | $400 to $900 | Low compression, accessories still good |
| Full engine replacement | $800 to $2,000+ | Catastrophic internal failure |
| Replace mower | $1,800 to $4,000+ | Deck and drive system also need major work |
The 917270773 safety interlocks can prevent starting; the engine should only start with the clutch/brake fully depressed and the PTO disengaged (see the 917270773 owner’s manual).
- Clicks but will not crank: battery charge, cable connections, starter wiring
- Cranks but will not start: fresh fuel, spark, air filter, choke operation
- Runs but cuts poorly: deck belt slip, bent blade, worn mandrel, clogged deck
DIY help: riding lawn mower engine clicks but doesnt turn over video
An engine swap can add years of service to a good tractor, but only if the deck and drivetrain are dependable. Checking interlocks and deck drive parts first prevents spending engine money on a mower that still will not perform.
Last updated: January 2026





