Craftsman 917378380 rotary lawn mower Parts

We don’t recommend using WD-40 on the deck of your Craftsman 917378380 rotary lawn mower. It can leave an oily film that attracts dust and grit, and it does not replace the cleaning and mowing practices that prevent clumping and buildup.

What to do instead (works better than sprays)

• Clean the underside of the mower housing after each use; scrape off grass and debris (with the spark plug wire disconnected).
• Avoid mowing wet grass; wet clippings clump and stick.
• Raise the cutting height in tall or heavy grass to reduce clumping.
• Slow your walking speed and overlap passes in heavy cutting.
• Keep the engine area clear of clippings and chaff to maintain airflow.

For the model-specific cleaning and mowing tips, follow the steps in the owner's manual.

Quick comparison: WD-40 vs. proven prevention

Option	Helps prevent sticking?	Best use case	Main downside
WD-40	Short-term at best	Temporary slicking	Oily film can collect dirt and make cleanup messier
Scraping/cleaning after mowing	Yes	Every mow	Takes a few minutes
Mowing when grass is dry	Yes	Routine mowing	Timing dependent
Higher cut height + slower pace	Yes	Tall, thick, or damp grass	May require a second pass

Why it matters

Grass buildup under the deck reduces airflow and lift, which leaves clumps, hurts bagging and mulching performance, and can overload the engine. Keeping the housing clean and adjusting mowing technique gives the most consistent results.

If you want a tool-focused approach for safe blade access during cleaning, see our lawn mower blade removal tool guide.

Last updated: February 2026

For the Craftsman rotary lawn mower model 917378380, use regular unleaded gasoline with a minimum of 87 octane; 89 octane is not needed for normal operation. We also recommend fresh fuel and avoiding higher-ethanol blends to reduce starting and fuel-system problems (see the 917378380 owner's manual).

What to use (and what to avoid)

• Use: fresh, clean regular unleaded gas (87 octane minimum)
• Avoid: old or stale gas (especially fuel sitting more than about 30 days)
• Avoid: mixing oil into the gasoline (this is a 4-cycle engine setup)
• Avoid: overfilling the tank; fill to the bottom of the filler neck
• Avoid: storing the mower indoors with fuel in the tank

Quick comparison: 87 vs 89

Fuel choice	Works in model 917378380?	When it makes sense	What you gain
87 octane (regular)	Yes (recommended)	Everyday mowing	Correct performance for this engine
89 octane (mid-grade)	Yes	Only if 87 is unavailable	Typically no noticeable benefit

Why it matters

Using the correct octane keeps your mower running as designed, but fuel freshness matters more than paying for higher octane. Stale fuel and moisture-related fuel issues are common causes of hard starting and rough running.

Fuel tips that prevent no-start issues

• Buy gas in small quantities you will use quickly
• If the mower will sit for 30 days or longer, run it dry or drain the tank as directed in the manual
• Wipe up spills right away and keep fuel away from heat or open flame
• If the mower won’t start after storage, replace the fuel first before chasing ignition or carburetor issues

Last updated: February 2026

The Craftsman 917378380 is a mower model number, so the price depends on whether you’re buying a complete used mower or just replacement parts. On our model 917378380 parts list, you can price and order the exact parts you need, and you can confirm specifications in the owner's manual.

What you can buy for model 917378380

Most customers shopping this model page are replacing wear items or drive components, not purchasing a whole mower.

Common examples from the parts list include:

• Drive and motion parts such as the lawn mower ground drive belt, 3/8 x 32-1/2-in 532175436
• Handle and control items such as the selector knob 532701037
• Bagging parts such as the lawn mower grass bagger 532410677
• Wheel and axle hardware such as the dust cover 581840401

Typical price ranges (what to expect)

Because complete-mower pricing varies by condition and location, we focus on parts pricing for Craftsman rotary lawn mowers like the 917378380.

Item type	Typical range	Notes
Small hardware (nuts, E-rings, washers)	$3 to $10	Often replaced during wheel or handle repairs
Belts and cables	$25 to $40	Common fix for “won’t move” or drive slipping
Wheels, gearcase parts, bagger assemblies	$40 to $140+	Larger assemblies cost more

How to get the right total cost for your repair

Use this approach so you only buy what your mower actually needs:

• Identify the symptom (won’t move, poor cut, bagging issues, etc.).
• Match the symptom to the drive system, blade system, or handle controls.
• Confirm the correct part by diagram and description for model 917378380.
• Replace related wear items together when practical (for example, belt plus drive cable).
• Verify adjustments after installation (handle height, cutting height, drive engagement).

Why it matters

Pricing a repair by part (instead of guessing at a full mower price) keeps costs predictable and helps you restore safe cutting and reliable self-propelled drive performance.

Last updated: February 2026

Your Craftsman walk-behind mower’s model number is printed on the product identification label; for this unit it’s 917378380. On most Craftsman rotary mowers, that label is on the mower deck near the rear discharge area or under the rear guard; confirm the exact label location in the 917378380 owner's manual.

Where to look on a Craftsman walk-behind mower

Check these common spots on the mower (wipe off grass and dirt first so the label is readable):

• On top of the mower deck, usually toward the rear
• Under the rear guard or rear discharge flap area
• Near the rear wheels on the deck housing
• On the handle support area near the deck (less common)
• On the underside of the deck lip (you may need a flashlight)

What number you need (and how to write it)

For parts lookup and diagrams, we recommend using the full model number exactly as shown.

Item	Example for this mower	Why it matters
Model number	917378380	Identifies the correct parts diagrams
Product type	Craftsman rotary lawn mower	Helps narrow parts categories
Engine model (if listed)	Varies by engine brand	Used for engine-specific parts like carburetor or ignition

Tips to avoid ordering the wrong parts

Once you find the label, match it carefully before selecting parts like a drive belt, wheel, or blade adapter.

• Copy the model number character-for-character (no spaces unless the label shows them)
• If the label shows a “model” and a separate “product number,” use the model for diagrams
• Use the exploded views in the manual to confirm part placement before ordering
• If you’re troubleshooting self-propel issues, compare your drive system parts to the diagrams (belt, cable, gear case)

Why it matters

Craftsman model numbers can look similar, but small differences change the deck, drive system, and hardware. Using the exact model number ensures you get the correct fit for items like the lawn mower ground drive belt 532175436 or lawn mower drive cable 583134601.

Last updated: February 2026

Common problems on the Craftsman 917378380 rotary lawn mower are no-start conditions (stale fuel, dirty air filter, bad spark plug, disconnected plug wire), loss of power from heavy grass or deck buildup, excessive vibration from a loose or damaged blade system, and a starter rope that is hard to pull. For model-specific troubleshooting steps, use the owner's manual.

Quick symptom checklist (most common)

• Won’t start: stale fuel, dirty air filter, spark plug or plug wire issue
• Starts then dies / runs rough: fuel contamination, restricted airflow, blade system issue
• Loss of power: cutting too low, mowing too fast, grass packed under the deck, oil level off
• Excessive vibration: worn or bent blade, loose blade bolt, damaged blade adapter
• Starter rope hard to pull: blade dragging in grass, brake engaged when control bar released, bent crankshaft, broken blade adapter

What to check first (fast, high-impact)

1. Fuel: Drain old gas and refill with fresh gasoline if fuel is stale or has water.
2. Air filter: Clean or replace if dirty.
3. Spark plug and wire: Make sure the wire is firmly connected; replace the plug if fouled.
4. Control bar: Hold the control bar against the handle when starting; a released control bar can prevent starting.
5. Blade system: Tighten the blade bolt and inspect the adapter; a loose blade or broken adapter can cause no-start and vibration. If you need the replacement part, use the lawn mower blade adapter 532418373.

Troubleshooting guide by symptom

Symptom	Most likely causes	What we recommend
Won’t start	Dirty air filter, out of fuel, stale/watered fuel, bad plug, loose blade/adapter, control bar released	Refresh fuel, service air filter, check plug/wire, inspect blade/adapter
Loss of power	Cutting too low, deck packed with clippings, dirty air filter, oil level too high	Raise cutting height, clean underside, service air filter, verify oil level
Excessive vibration	Worn/bent blade, loose blade, broken adapter, bent crankshaft	Stop mowing, inspect blade/adapter, correct fasteners, replace damaged parts
Starter rope hard to pull	Blade dragging in grass, brake engaged, bent crankshaft, broken adapter	Raise height, clear deck, inspect blade/adapter before restarting

Why it matters

These issues are connected: stale fuel and restricted airflow cause hard starting and poor power, while a loose blade or damaged adapter can create vibration and even keep the engine from starting. Fixing the root cause protects the crankshaft, deck, and drive system.

Last updated: February 2026