Who makes engines for Craftsman lawn mowers?
Craftsman lawn mowers have been sold with engines from multiple manufacturers over the years; the most common engine makers you will see are Briggs & Stratton, Kohler, and Kawasaki. The exact engine manufacturer depends on the specific mower model and the engine model stamped on the blower housing.
How to identify the engine maker on your Craftsman mower
Use the engine’s ID tag, not the mower deck badge. On many walk-behind and riding mowers, the engine model and spec numbers are stamped or printed on the blower housing, valve cover area, or a label near the starter.
- Look for an engine brand name cast into the shroud (Briggs & Stratton, Kohler, Kawasaki)
- Find the engine model and type/spec numbers (these are more reliable than horsepower labels)
- Match those numbers when ordering tune-up or carburetor parts
- If the label is missing, compare the carburetor style, air filter housing, and ignition layout
What this means for Craftsman model 143005512
For Craftsman engine model 143005512, parts selection is based on this engine model number. Common service parts on this model page include carburetor and ignition components such as the ignition module 34443D, needle seat 631021B, and carburetor rebuild kit 632760B.
Quick guide: engine maker vs. what you should use to order parts
| What you see | What it tells you | What to use for parts |
|---|---|---|
| “Craftsman” on the mower | Mower brand | Engine model number and spec/type |
| Briggs/Kohler/Kawasaki name | Engine manufacturer | Engine model and spec/type |
| 143005512 | Engine model identifier | Use this model to match parts |
Why it matters
Engine makers use different carburetors, ignition coils, gaskets, and fuel line sizes. Using the correct engine identification helps you avoid repeat issues like hard starting, surging, fuel leaks, or no-spark conditions.
For ordering, we recommend using the parts list for model 143005512 first; you can also search by model number on Sears PartsDirect if you are working on a different Craftsman mower or engine.
Last updated: February 2026
What are the common problems with Craftsman lawn mowers?
Common Craftsman lawn mower problems usually come down to fuel delivery, ignition, or airflow. On Craftsman engine model 143005512, the most frequent causes are stale fuel clogging the carburetor, air leaks at gaskets or O-rings, a weak spark from the ignition system, or restricted airflow from a dirty filter.
Quick checks we recommend first
- Drain old gas and refill with fresh fuel (stale fuel is the top cause of hard starting).
- Prime correctly; a cracked primer bulb can prevent proper fuel draw.
- Inspect fuel line routing and condition for cracks, soft spots, or leaks.
- Check for loose carburetor mounting screws and obvious gasket leaks.
- Verify spark; no spark often points to the ignition module.
Most common symptoms and likely causes
| Symptom | Most likely cause | Parts that often fix it |
|---|---|---|
| Won’t start | Clogged carburetor passages, air leak, no spark | Needle seat 631021B, ignition module 34443D |
| Starts then dies | Fuel restriction, carburetor bowl issue, air leak | Line 29774, Craftsman lawn & garden equipment engine carburetor float bowl 631867 |
| Surges at idle | Lean condition from air leak or dirty carb | Craftsman lawn and garden equipment engine carburetor gasket 26756, Craftsman lawn & garden equipment engine carburetor o-ring 632547 |
| Fuel leaking | Worn needle/seat, damaged bowl seal | Needle seat 631021B, Craftsman lawn & garden equipment o-ring 35499 |
| No spark | Failed ignition module, damaged wiring | Ignition module 34443D |
Carburetor-related problems (most common)
Old fuel leaves varnish that blocks jets and passages, so the engine may only run on prime or may die under load. If you see fuel seepage or inconsistent priming, the primer bulb and sealing parts are the first places we look.
- For priming issues: Craftsman lawn & garden equipment engine carburetor primer bulb (red) 640259
- For rebuild-level fixes: tecumseh lawn and garden equipment engine carburetor rebuild kit 632760B
Why it matters
Running lean (from clogged fuel circuits or air leaks) can cause surging, overheating, and hard starting. Fixing small sealing issues like a carburetor gasket or O-ring often restores normal starting and smooth operation without replacing major engine components.
Getting the right parts
We recommend ordering replacement parts for Craftsman model 143005512 from the parts list for this model; you can also search by model number on Sears PartsDirect if you are working on a different Craftsman mower or engine variant.
Last updated: February 2026
How to look up Craftsman model number?
To look up the correct Craftsman model number for parts and diagrams, we match the ID from the equipment’s model tag to the exact model listing. For Craftsman engine model 143005512, use the full number exactly as shown on the tag when searching parts.
Where to find the model number on Craftsman outdoor power equipment
Model tag locations vary by product, but these are the most common spots to check:
- Riding mower or lawn tractor: on the frame under the seat, or on the underside of the seat
- Walk-behind mower: on the rear deck near the bagger door, or on the side of the deck
- Snowblower: on the rear of the frame near the wheels, or behind the engine
- Tiller: on the frame near the engine mount
- Engine-only tag (Tecumseh-style 143.xxxxxx): stamped or labeled on the blower housing or shroud
How to use the model number to get the right parts
Once you have the model number, use it to pull the correct parts breakdown and order the exact match.
- Enter the full model number with no spaces (example: 143005512)
- Use the parts list for that model to confirm part names and IDs
- Match by part ID when possible (it is the most precise identifier on our site)
- If your tag shows extra numbers, write them down; they can help confirm the exact version
Common parts people look up by model
Here are examples of parts on this model’s parts list that often come up during troubleshooting:
| Symptom | Common area to check | Example part on this model |
|---|---|---|
| Hard starting or needs priming | Carburetor/primer | Craftsman lawn & garden equipment engine carburetor primer bulb (red) 640259 |
| Fuel leak or flooding | Carburetor sealing | Needle seat 631021B |
| No spark | Ignition | Ignition module 34443D |
| Runs rough, surges | Air/fuel intake sealing | Craftsman lawn and garden equipment engine carburetor gasket 26756 |
Why it matters
Craftsman outdoor power equipment often has similar-looking engines and carburetors across different versions. Using the exact model number prevents ordering the wrong ignition module, gasket, or carburetor parts and saves time during repair.
If you need to search beyond this model’s parts list, we also support model number search on Sears PartsDirect.
Last updated: February 2026
What engine is in a Craftsman lawn mower?
The engine in a Craftsman lawn mower depends on the mower’s model number. For the Craftsman 143005512 lawn and garden engine, the engine is identified by model 143005512 (this is the engine model itself), and you can match the correct carburetor, ignition, and gasket parts from the parts list for this engine or search by mower model on Sears PartsDirect.
How to identify the engine on your Craftsman mower
Use the mower’s model tag first, then confirm the engine model on the engine shroud or valve cover area.
- Find the mower model number on the deck or rear frame label.
- Find the engine model number stamped/printed on the engine housing (often near the recoil starter).
- Match the engine model to the parts list (carburetor, ignition, fuel system parts).
- If the mower brand is Craftsman but the engine brand differs (common), use the engine model for engine parts.
- If the mower starts hard or surges, confirm fuel and carburetor parts match the engine model.
Common engine-related parts customers replace on model 143005512
If your Craftsman 143005512 engine is hard to start, won’t stay running, or leaks fuel, these parts are frequent fixes:
- Craftsman lawn & garden equipment engine carburetor primer bulb (red) 640259
- Needle seat 631021B
- Craftsman lawn and garden equipment engine carburetor gasket 26756
- Ignition module 34443D
Quick symptom-to-part guide
| Symptom | Most likely area | Parts to check for 143005512 |
|---|---|---|
| Won’t start, no spark | Ignition | Ignition module/coil |
| Starts then dies, needs choking | Carburetor/fuel | Primer bulb, needle/seat, gaskets |
| Fuel leaking from carb | Carburetor | Needle seat, float bowl gasket surfaces |
| Surging at idle | Air leak/fuel restriction | Carburetor gasket, fuel line |
Why it matters
Craftsman mower model numbers and engine model numbers are not the same thing. Using the correct engine model (like 143005512) ensures you get the right carburetor rebuild parts, ignition module, and gaskets so the repair works the first time.
Last updated: February 2026
