Craftsman 917273643 lawn tractor Parts

The Craftsman lawn tractor model 917273643 is equipped with an 18.5 HP gasoline engine (a low-emission design) and uses regular unleaded fuel. For the exact operating and maintenance details for your tractor’s engine, follow the 917273643 owner's manual.

What we can confirm for model 917273643

From the model-specific specifications, your tractor is set up for typical single-cylinder lawn tractor service items and tune-up parts.

• Fuel: Unleaded regular gasoline
• Fuel capacity: 4.0 gallons
• Spark plug: Champion RC12YC, gap 0.030 in
• Oil type: SAE 30 (above 32°F) or SAE 5W-30 (below 32°F)
• Oil capacity: 3.5 pints with filter, 3.0 pints without filter

Engine brand and configuration (what varies)

This model’s documentation confirms horsepower and key specs, but it does not identify the engine’s manufacturer name (for example, Briggs & Stratton) or the exact engine model number in the excerpted information we have for 917273643.

A practical way to confirm the exact engine make and model is to check the engine ID label on the blower housing or valve cover, then use that engine model number when ordering engine-specific parts.

Quick reference table

Spec	Model 917273643 value
Horsepower	18.5 HP
Fuel type	Unleaded regular
Fuel capacity	4.0 gallons
Spark plug	Champion RC12YC (0.030 in gap)

Why it matters

Knowing the correct engine details helps you buy the right maintenance items (spark plug, oil, filters) and prevents hard-starting, rough running, and premature wear.

Last updated: January 2026

For the Craftsman lawn tractor model 917273643, the engine manufacturer is not identified by name in the model’s documentation; Craftsman-branded tractors in this class are commonly equipped with engines supplied by major small-engine makers such as Briggs & Stratton, Kohler, or Kawasaki. For the most accurate match, we recommend confirming the engine’s model/type code on the engine itself and cross-checking it with the 917273643 owner’s manual.

How to identify the engine maker on model 917273643

Use the engine’s ID tag, not the tractor hood decal. On most riding mowers, the engine label is on or near the blower housing, valve cover, or above the spark plug.

• Look for an engine model/type/code (Briggs & Stratton) or spec/model number (Kohler, Kawasaki)
• Write down the full string exactly as shown
• Compare that engine ID to parts diagrams and tune-up parts listings
• If the label is missing, check for a stamped number on the shroud or valve cover
• Use the tractor model number 917273643 only to find tractor parts; use the engine ID to find engine-specific parts

Why the manual may not name the engine brand

On many Craftsman tractors, the tractor model number (like 917273643) identifies the chassis and deck configuration, while the engine supplier can vary by production run or replacement history. That’s why the engine’s own tag is the best source.

Quick reference: where to look and what you’ll find

What you’re checking	Where to find it	What it tells you
Tractor model number	Frame tag under seat or on chassis	Which tractor parts fit
Engine model/type code	Engine shroud/cover label	Who made the engine and which engine parts fit
Deck/blade info	Mower deck tag	Deck size and blade style

Why it matters

Ordering the wrong ignition parts, air filter, fuel filter, or spark plug is one of the most common causes of repeat no-start and poor-running issues. Matching parts to the engine ID prevents misfits and saves time.

Last updated: January 2026

Replacing the engine on your Craftsman lawn tractor model 917273643 is usually worth it only when the tractor is otherwise in great shape and the total repair cost stays under about half the price of a comparable replacement tractor. If the transmission, deck, or steering also needs major work, replacement is typically the better value.

How we decide for model 917273643

We use a cost-versus-condition check, then confirm maintenance and specs in the 917273643 owner’s manual.

• Compare total engine swap cost (engine, hardware, fluids, labor) to the tractor’s replacement cost.
• Check the mower deck and spindle/mandrel area for wear, noise, or vibration.
• Consider hours of use and how well it has been maintained (oil changes, air filter, belts).
• Factor in downtime and whether you can do the work yourself.

Quick decision guide

Situation	Usually best choice	Why
Tractor is solid; deck and transmission are healthy	Replace engine	You keep a known-good chassis and deck
Multiple major systems are worn (engine + transmission/deck)	Replace tractor	Costs stack up fast
Only performance issues (rough running, power loss)	Repair engine systems first	Often cheaper than a full engine

Parts that often make “repair first” smarter

Before committing to an engine replacement, we typically check common wear items that can mimic a “bad engine”:

• Fuel quality and fuel delivery (stale gas, restricted flow)
• Air filter and cooling fins (overheating and power loss)
• Spark plug and ignition tune-up items
• Blade drive load issues (binding deck components, belt drag)
• Safety interlock problems that cause stalling

If your tractor vibrates, cuts unevenly, or makes a grinding noise from the deck, inspect the mandrel/spindle system; a worn mandrel can overload the engine. A common deck component to check is the husqvarna lawn tractor mandrel assembly 532130794.

Why it matters

An engine swap can restore reliability, but it only pays off when the rest of the Craftsman 917273643 is not near the end of its service life. A quick inspection prevents spending engine money on a tractor that still has expensive deck or drivetrain problems.

Last updated: January 2026