What year was the Craftsman 143955003 made?
Craftsman model 143955003 is an engine model number, not a single dated product run; the exact build year is identified from the engine’s spec/date code stamped on the blower housing or valve cover area. We use that code to match the correct carburetor, ignition, and gasket parts for your engine.
Where to find the build date information
Look for a stamped or printed code on the engine itself (not the mower or tractor frame). Common spots include:
- Blower housing (recoil starter shroud)
- Valve cover area
- Engine block near the spark plug
- A tag or decal near the carburetor
If the code is dirty or faint, wipe the area and use a flashlight at an angle to make the stamping easier to read.
How the “year” works for this engine model
For many Craftsman-branded lawn and garden engines, the model number (143955003) identifies the engine family and configuration, while the date/spec code identifies when that specific engine was built.
| What you have | What it tells us | What to do with it |
|---|---|---|
| Model number: 143955003 | Engine type and parts family | Use it to pull the correct parts diagrams |
| Spec/date code (stamped) | Build timing and exact variant | Use it to confirm the exact replacement part |
| Equipment model/serial (mower/tractor) | Year of the equipment | Helpful, but not the engine’s build date |
Parts that often depend on the exact spec/date code
Small differences by spec can change fitment for fuel and ignition components. These are common examples for 143955003:
- Carburetor and internal fuel parts such as the needle seat 631021B
- Carburetor sealing parts such as the Craftsman lawn and garden equipment engine carburetor gasket 26756
- Ignition components such as the lamination 34443D
- Air intake service parts such as the lawn & garden equipment engine air filter 36046
Why it matters
Using the correct build identification prevents hard-starting, flooding, surging, and no-spark issues caused by installing a similar-looking part that does not match your exact engine variant.
If you are ordering parts beyond what’s listed for 143955003, we recommend searching by the full model number on Sears PartsDirect to pull up the closest match and diagrams.
Last updated: February 2026
Who makes Craftsman 163cc engines?
Many Craftsman 163cc lawn mower engines are made by Briggs & Stratton (often sold as the 163cc EXi 725 Series). For your Craftsman engine model 143955003, the most reliable way to confirm the original engine manufacturer is to match the model and spec information on the engine tag to the parts list and diagrams, then order the correct replacement parts.
How to identify who made your Craftsman 163cc engine
Look for an engine ID label stamped or printed on the engine shroud or valve cover area. Use these checks:
- Find the engine model and spec numbers on the engine tag (not the mower deck label).
- Compare that information to the parts breakdown for model 143955003.
- If the engine uses Tecumseh-style carburetion and ignition components, that points to a Tecumseh-built engine family.
- If the engine uses Briggs-style labeling and part families, that points to Briggs & Stratton.
- Use the parts list to confirm by ordering a known-fit component (air filter, primer, carburetor parts).
Parts on this model page that help confirm the engine family
Several parts listed for model 143955003 align with common Tecumseh small-engine part families. These are practical “fit check” items when you are identifying the engine:
- Lamination 34443D (ignition coil)
- Carburetor 640025C
- Needle seat 631021B
- Primer 36045A
- Lawn & garden equipment engine air filter 36046
Quick comparison: what you are checking
| What you check | Where to look | What it tells you |
|---|---|---|
| Engine model/spec tag | Engine shroud/cover | The actual engine manufacturer and family |
| Ignition coil style | Flywheel side | Often brand-family specific |
| Carburetor and primer parts | Air intake/carb area | Helps confirm the correct parts family |
| Air filter shape and housing | Air box | Confirms the correct filter and gasket set |
Why it matters
Craftsman is the equipment brand, but engines can be sourced from different manufacturers across product lines and years. Confirming the engine family prevents ordering the wrong carburetor, ignition coil, or air filter, and it speeds up troubleshooting for no-start, surging, and hard-start issues.
If you need to order parts beyond what is listed for model 143955003, we recommend searching by the full engine model/spec information on Sears PartsDirect.
Last updated: February 2026
What are the parts of a lawn mower engine?
A typical lawn mower engine (including Craftsman model 143955003) is built around fuel delivery, air intake, ignition, and rotating internal parts that create power. Common engine parts include the fuel tank, carburetor, air filter, ignition coil, flywheel, crankshaft, and seals and gaskets that prevent leaks.
Main lawn mower engine parts (what they do)
- Fuel tank: Stores gasoline and feeds the fuel line.
- Carburetor: Mixes fuel and air for combustion (often serviced with gaskets, O-rings, and a primer bulb).
- Air filter system: Filters dirt before air enters the carburetor.
- Ignition system: Creates spark timing (ignition coil plus spark plug).
- Recoil starter: Spins the engine fast enough to start.
- Flywheel: Smooths engine rotation and helps ignition timing.
- Crankshaft and piston: Convert combustion force into spinning power.
Parts you will commonly replace on Craftsman 143955003
These are frequent maintenance or “no-start” repair items we see on small engines:
- Lawn & garden equipment engine air filter 36046
- Craftsman lawn & garden equipment engine pre-filter 36634
- Primer 36045A
- Needle seat 631021B
- Craftsman lawn and garden equipment engine carburetor gasket 26756
- Craftsman lawn & garden equipment engine carburetor o-ring 632547
Quick symptom-to-part checklist
| Symptom | Most likely engine area | Parts on this model page to check |
|---|---|---|
| Starts then dies | Fuel delivery | Primer, needle seat, carburetor gasket/O-ring |
| Runs rough, black smoke | Air intake or carburetor | Air filter, pre-filter, carburetor |
| Fuel smell or wet spots | Sealing surfaces | Carburetor gasket/O-ring, oil seal |
| No spark | Ignition | Ignition coil (lamination), flywheel |
Why it matters
Knowing the major engine sections helps you troubleshoot faster and order the right replacement part the first time. On model 143955003, most “won’t start” issues trace back to air filtration or carburetor sealing parts, not major internal components.
You can order replacement parts for Craftsman 143955003 from the parts list for this model, or search by model number on Sears PartsDirect.
Last updated: February 2026
Where can I get Craftsman replacement parts?
You can get Craftsman replacement parts for your Craftsman lawn and garden engine model 143955003 directly from the parts list for this model to match the exact fit. For broader model-based searching across Craftsman equipment, you can also use Sears PartsDirect.
Best way to buy the correct part for model 143955003
Start by matching the part to your exact model number 143955003 and the symptom you are fixing (no-start, surging, fuel leak, hard starting). Common maintenance and repair parts available for this engine include:
- Lawn & garden equipment engine air filter 36046 for restricted airflow and rich running
- Primer 36045A for hard starting and poor priming
- Needle seat 631021B for carburetor flooding or fuel overflow
- Craftsman lawn and garden equipment engine carburetor gasket 26756 for air leaks around the carburetor
- Tecumseh lawn and garden equipment engine carburetor rebuild kit 632760B for worn carburetor seals and internal fuel metering issues
Quick troubleshooting guide (so you order the right part)
Use this fast “symptom to part” check before ordering:
| Symptom | Most common cause | Parts to consider for 143955003 |
|---|---|---|
| Starts then dies | Fuel delivery issue, dirty carb | Primer, needle seat, carburetor gasket |
| Surges at idle | Vacuum leak, carb issue | Carburetor gasket, carburetor O-ring |
| Fuel leaking or flooding | Needle not sealing, bowl issue | Needle seat, float bowl |
| Runs rough, black smoke | Air filter clogged | Engine air filter, pre-filter |
What to check before ordering
These checks prevent wrong-part returns and repeat repairs:
- Confirm the model number on the engine tag matches 143955003.
- Inspect the air filter and pre-filter; replace if dirty or oil-soaked.
- Drain old fuel and refill with fresh fuel before replacing carburetor parts.
- Check for wetness around the carburetor bowl and primer area (signs of flooding).
- Compare your existing part visually to the diagram and listing (especially carburetor and linkage parts).
Why it matters
Small-engine parts vary by carburetor style, gaskets, and linkage setup even within Craftsman. Using the model-specific parts list for 143955003 helps you get the correct fuel-system and tune-up parts the first time.
Last updated: February 2026
What brand engine does Craftsman use?
Craftsman uses engines from multiple manufacturers across its outdoor power equipment lineup. For engine model 143955003, the 143.XXXXXX numbering identifies it as a Tecumseh-manufactured engine; use the parts list for this exact engine when ordering replacements from Sears PartsDirect.
What engine brands Craftsman commonly uses
Depending on the mower, tractor, or tiller model and production year, Craftsman equipment is commonly powered by:
- Tecumseh (common on many older Craftsman engines; includes 143.XXXXXX engine models)
- Briggs & Stratton
- Kohler
- Kawasaki
- Other OEM suppliers in certain product lines
How to confirm the engine brand on your specific machine
Even when the equipment is branded Craftsman, the engine maker is confirmed by the engine ID information.
- Find the engine model/spec label or stamping (often on the blower housing, shroud, or near the spark plug)
- Record the full engine model number and any spec or date code
- Match that engine model to the correct diagrams and parts list
- If the label is missing, compare key fuel and ignition parts to the breakdown for the engine model
Quick identification guide
| What you see on the engine ID | What it indicates | Why it helps |
|---|---|---|
| 143.XXXXXX (example: 143955003) | Tecumseh-manufactured engine | Parts and linkages are Tecumseh-specific |
| Briggs model/type/code | Briggs & Stratton engine | All three numbers narrow exact fit |
| Kohler model and spec | Kohler engine | Spec number controls carb and ignition variants |
Parts that often come up on Tecumseh 143955003 engines
These are common service items for starting, surging, or fuel leakage issues:
- Carburetor 640025C
- Primer 36045A
- Needle seat 631021B
- Lawn & garden equipment engine air filter 36046
- Tecumseh lawn and garden equipment engine carburetor rebuild kit 632760B
Why it matters
Engine brand and engine model control critical fit details such as carburetor linkage geometry, gasket shapes, and ignition components. Identifying 143955003 as a Tecumseh engine helps you choose parts that fit and tune correctly.
Last updated: February 2026
