How much does it cost to replace a riding lawn mower engine?
For the Craftsman lawn tractor model 917255451, a full engine replacement typically costs about $260 to $1,800 installed. Total price depends on the engine itself, whether any pulleys or belts must be transferred, and the labor time (often around 6 hours for a riding mower).
What drives the total cost
- Engine price: new, used, or rebuilt engines vary widely.
- Labor time: riding mower engines take longer than walk-behind engines.
- Extra parts: worn drive components often get replaced during the swap.
- Shop rates: local labor rates and minimum charges vary.
- Downtime costs: pickup, delivery, and seasonal demand can add fees.
Parts you may end up replacing at the same time
Even if you only plan an engine swap, we often see these wear items addressed during reassembly and testing:
- V-belt 532138255 (common ground drive belt wear or glazing)
- Engine pulley 532140186 (if the pulley is grooved, bent, or seized)
- Lawn tractor ground drive or blade drive belt 592855201 (if belt routing or tensioning shows damage)
- Fuel line, clamps, and fresh fuel (typical tune-up items)
Quick cost breakdown (typical ranges)
| Cost item | Typical range | Notes |
|---|---|---|
| Engine (part only) | $200 to $1,500+ | Biggest variable; depends on brand, HP, and availability |
| Labor | $300 to $900 | Often based on ~6 hours plus shop rate |
| Misc. parts and supplies | $20 to $200 | Belts, hardware, fuel system items, shop supplies |
Why it matters
An engine replacement can make sense when the tractor frame, deck, and transmission are in good shape. If the mower also has drive belt slip, vibration, or pulley wear, bundling those repairs avoids paying labor twice and helps the new engine perform correctly.
For maintenance that can prevent premature engine failure, use our how to tune up a riding lawn mower video as a checklist for fuel, air, and ignition basics.
Last updated: January 2026
Is it worth replacing a lawn mower engine?
Replacing the engine on a Craftsman lawn tractor model 917255451 is worth it when the mower deck, transmission, steering, and frame are still solid and the total engine swap cost stays well below the cost of a comparable replacement tractor. If the tractor has multiple worn systems, replacement usually makes more sense.
Quick decision checklist
- The deck shell is not rusted through and the spindles are not loose or noisy
- The tractor drives strongly (no slipping, weak hydro, or grinding)
- Steering and front axle are tight (no severe play)
- You can do the labor yourself or have a shop you trust
- The engine replacement cost is comfortably under about half the price of a similar new tractor
Costs and effort to plan for
Even with a “bolt-in” style swap, engine replacement typically includes more than the engine itself.
| Item | Typical need | Why it matters |
|---|---|---|
| Engine or short block | Required | Restores compression and reliability |
| Belts and pulleys | Often | Worn belts can slip and overheat |
| Fuel system refresh | Common | Old fuel and debris can ruin a new carb/engine |
| Tune-up parts | Common | Prevents hard starting and misfires |
If your deck has vibration, uneven cut, or a loud rumble, inspect the spindle/mandrel area before investing in an engine. A worn mandrel can make a “new engine” feel rough and can damage belts.
Parts on this model that often get addressed at the same time
- Lawn tractor ground drive or blade drive belt, 1/2 x 92-2/5-in 592855201 (belt wear, glazing, cracking)
- V-belt 532138255 (alternate belt size used on some setups)
- Husqvarna lawn tractor mandrel assembly 532130794 (bearing noise, wobble, blade vibration)
- Fuel tank assembly 532151346 (leaks, contamination, brittle fittings)
Why it matters
An engine swap can extend the life of a good chassis by years, but it only pays off when the rest of the tractor is dependable. Fixing a tired engine on top of a worn deck drive, steering, and fuel system usually turns into a bigger project than planned.
Last updated: January 2026
What engine does Craftsman riding mower use?
The Craftsman riding mower model 917255451 uses a single-cylinder gasoline engine (a common configuration for front-engine lawn tractors). For the exact engine brand, displacement, and horsepower for your specific tractor, match the engine ID tag on the engine shroud to the correct parts breakdown.
How to identify the exact engine on model 917255451
Look for an engine identification label (usually on the blower housing, valve cover area, or near the starter). Record these items:
- Engine manufacturer (commonly Briggs & Stratton, Kohler, or Tecumseh on tractors of this style)
- Model number
- Type number
- Code or serial number
- Any spec number shown on the tag
Once you have the engine ID, you can confirm the correct tune-up and fuel system parts (air filter, spark plug, fuel line, carburetor parts) for that exact engine.
Quick checks that help confirm you have the right engine parts
Even before ordering parts, these checks prevent mismatches:
- Compare the engine tag numbers, not just the tractor model number
- Verify the crankshaft style and PTO setup (varies by engine family)
- Confirm whether your tractor uses a manual choke or auto-choke setup
- Check the fuel tank outlet location and fuel line routing
- If you are replacing the ignition key, match the key style to the switch
A common replacement item on this tractor is the molded ignition key 532140403, which fits the ignition switch style used on many Craftsman-built tractors.
Common symptoms vs likely engine-related causes
| Symptom | What it often points to | What to check first |
|---|---|---|
| Clicks but won’t crank | Weak battery, bad connections, starter circuit issue | Battery voltage, terminals, solenoid wiring |
| Cranks but won’t start | Fuel delivery or ignition issue | Fresh fuel, spark, air filter |
| Starts then dies | Safety interlock, fuel restriction | Seat switch/brake switch, fuel flow |
For step-by-step diagnosis, use riding lawn mower engine spins but wont start video or riding lawn mower engine clicks but doesnt turn over video.
Why it matters
The tractor model number 917255451 identifies the chassis and deck, but the engine tag identifies the exact engine build. Using the engine ID prevents ordering the wrong carburetor, ignition parts, or tune-up components.
Last updated: January 2026
