Craftsman 316731973 gas line trimmer Parts

To replace trimmer line on your Craftsman 316731973 gas line trimmer, we remove the spool, load the correct diameter line in equal lengths, and wind it evenly in the direction shown on the spool so the line feeds smoothly without tangling. See the 316731973 owner's manual for the exact head style and line size.

Steps to reload the trimmer line

• Shut the engine off and let the muffler cool; disconnect the spark plug boot for safety.
• Clean grass and debris from the bump head and debris shield so the spool seats correctly.
• Press the head tabs (or remove the cap, depending on your head) and lift out the spool.
• Cut two equal lengths of trimmer line (most bump heads use two pieces); keep ends clean and straight.
• Feed each line end into the spool eyelets/slots and wind the line tightly and evenly.
• Keep the wraps neat with no crossing or overlapping; this prevents binding and tangles.
• Reinstall the spool and cap; pull both line ends to confirm they move freely.

Winding tips that prevent tangles

Most feed problems come from loose wraps or crossed line. Use these checks:

What you see	What it usually means	What to do
Line will not advance	Line crossed or jammed	Rewind with tight, even wraps
Line advances but breaks fast	Line too thin or brittle	Use the line size in the manual; replace old line
Head vibrates	Unequal line lengths	Recut equal lengths and reload

Quick parts check while you are there

If the head still will not feed after a careful reload, inspect these common wear points:

• Spool eyelets for grooves or sharp edges
• Bump knob/cap for cracks
• Spring (if used) for rust or collapse
• Debris shield alignment

If the engine is hard to start after maintenance, service ignition and fuel basics; a fresh plug often helps. The line trimmer screw 9054 is an example of a small fastener used on this model that should be tightened securely if removed.

Why it matters

Correct line loading reduces drag on the clutch and drive system, improves cutting performance, and helps the bump head feed consistently so you spend less time stopping to fix jams.

Last updated: January 2026

If your Craftsman gas line trimmer model 316731973 is flooded, clear the excess fuel by opening the choke, holding the throttle wide open, and pulling the starter several times until it begins to fire. Then return to the normal starting position and restart using the steps in the 316731973 owner's manual.

Quick unflood steps (works for most 2-cycle trimmers)

• Move the stop switch to ON/RUN.
• Set the choke to OFF/OPEN (no choke).
• Hold the throttle wide open (full trigger).
• Pull the recoil starter 6 to 12 times to clear the cylinder.
• If it starts briefly, keep the throttle slightly open and let it run 30 to 60 seconds to dry out.
• If it still will not start, remove and dry the spark plug, then try again.

Spark plug check (most common fix)

A wet spark plug will not ignite the fuel mix. Drying or replacing it often gets you running quickly.

What you see on the plug	What it means	What to do
Wet with fuel	Flooded	Dry plug, clear cylinder, restart with choke open
Black and sooty	Rich mix or dirty air filter	Clean/replace air filter, check choke use
Dry and light tan	Normal	Look for fuel delivery or ignition issue

If the plug is fouled or the electrode is worn, replace it with the exact match listed for this model: mtd lawn & garden equipment engine spark plug 794-00082.

Why flooding happens (and how to prevent it)

Flooding usually comes from too much choking or repeated pulls without the engine firing. Using fresh fuel mix and a clean air filter helps the engine light off faster, so you do not over-prime it.

If it keeps flooding

• Check the air filter; a restricted filter can make starting harder (and lead to over-choking). The correct replacement is mtd line trimmer air filter 751-12833.
• Use fresh, properly mixed 2-cycle fuel; old fuel causes hard starting.
• If it only starts with the choke off and dies when you touch the throttle, the carburetor may need service.

Last updated: January 2026

For the Craftsman 316731973 gas line trimmer, we use straight, fresh unleaded gasoline in the fuel tank and 4-cycle engine oil in the crankcase; you do not mix oil into the gas. Add and check engine oil at the oil fill before each use.

What to put in it

• Gasoline: fresh unleaded gasoline (no oil mixed in)
• Engine oil: 4-cycle small-engine oil added through the oil fill
• Mix ratio: none (this model uses separate oil and gas)
• Best practice: use fresh fuel and keep the oil at the proper level

Quick reference

Item	What to use	Where it goes
Fuel	Unleaded gasoline	Fuel tank
Lubrication	4-cycle engine oil	Crankcase via oil fill

How we recommend fueling and checking oil

• Turn the trimmer off and let the engine cool.
• Fill the fuel tank with fresh unleaded gasoline.
• Check the oil level at the oil fill; top off as needed.
• If the trimmer was stored, drain old fuel and refill with fresh gasoline.
• Follow the exact oil type and capacity listed in the Craftsman 316731973 owner's manual.

If it was run with mixed gas

Running oil-mixed fuel in a 4-cycle trimmer can cause smoke, plug fouling, and poor running. These steps restore normal operation:

• Drain the fuel tank and refill with straight unleaded gasoline.
• Inspect and replace a fouled plug if needed using mtd lawn & garden equipment engine spark plug 794-00082.
• Clean or replace the air filter using mtd line trimmer air filter 751-12833.
• Verify the oil level using the oil fill system (oil is separate from fuel).

Why it matters

This Craftsman model uses a separate oil reservoir for lubrication. Keeping gas and oil separate prevents hard starting, excessive smoke, and engine damage.

Last updated: January 2026