Who makes MTD engines?
MTD lawn tractors like model TMO-33931A are built by MTD, but the engines are sourced from multiple manufacturers depending on the tractor’s year, price point, and engine family. You will commonly see Powermore (MTD-branded), Briggs & Stratton, or Kohler on MTD equipment.
How to identify who made the engine on your TMO-33931A
Check the engine’s ID label (usually on the blower housing, valve cover, or near the starter). Use the engine model and type code on that label, not the tractor model number.
- Look for an engine brand badge: Powermore, Briggs & Stratton, Kohler
- Find the engine model and spec/type numbers
- Match the numbers to the correct tune-up and service parts
- If the label is missing, note the engine’s general layout (single-cylinder vs V-twin, air filter style, carb location)
- Use the tractor parts diagrams to confirm related hardware and mounting pieces
Common engine sources you’ll see on MTD tractors
MTD has used different engine suppliers across product lines and years. Here’s a practical way to think about it:
| What you see on the engine | What it usually means | What to do next |
|---|---|---|
| Powermore badge | MTD-branded engine (often built by an outside engine manufacturer) | Use the engine model/spec to buy filters, plugs, and carb parts |
| Briggs & Stratton badge | Briggs-built engine | Use Briggs model-type-code for parts |
| Kohler badge | Kohler-built engine | Use Kohler model/spec for parts |
Why it matters
Engine maker determines the correct maintenance parts (spark plug, air filter, fuel filter, starter, carburetor parts) and the right service specs. Using only the tractor model can lead to ordering the wrong engine parts.
Parts tip for repairs on this tractor
If you are doing a repair while identifying the engine, it’s common to replace missing or damaged fasteners and hardware at the same time. For example, a correct mounting fastener like the MTD lawn tractor screw 710-0599 can help you finish reassembly without improvising.
Last updated: February 2026
What does the abbreviation TMO-33931A stand for?
On MTD equipment, TMO-33931A is the model number for a specific front-engine lawn tractor; it is not an abbreviation with a separate “stands for” definition. We use TMO-33931A to match the correct diagrams and replacement parts for your tractor.
What TMO-33931A means on your tractor
- TMO is part of MTD’s model-number prefix used for product identification.
- 33931A is the unique sequence that distinguishes this tractor from similar MTD models.
- The full model number is what matters when selecting parts such as belts, spindles, tires, and brake components.
- Meanings of “TMO” in other contexts (sports, military, texting) do not apply to this tractor.
Where you’ll use the model number (and why it matters)
Using the exact model number helps prevent ordering the wrong part, especially for items that vary by deck setup, transmission type, or brake linkage.
Common part categories that depend on the exact model:
- Drive and deck belts
- Spindles and pulleys
- Brake parts and linkages
- Wheels and tires
- Electrical starting components
Quick examples from this model’s parts list
| What you’re fixing | Example part you might match by model | Why model matching matters |
|---|---|---|
| Tractor will not move or slips | Speed belt 754-0280 | Belt length and profile must match the exact drive setup |
| Deck discharge issue (missing or damaged chute) | Chute deflector 16566 | Mounting points and deck opening size must match |
| Weak braking or brake drag | Return brake 732-0264 | Brake spring style and length must match the linkage |
How to confirm you’re using the right identifier
- Read the model label on the tractor frame (commonly under the seat or near the engine area).
- Match the model number exactly, including letters and hyphens: TMO-33931A.
- Use that model number when browsing diagrams and ordering parts.
Why it matters: Model-number accuracy is the fastest way to get the right MTD lawn tractor parts the first time and avoid fitment problems.
Last updated: February 2026
What lawn tractors are made by MTD?
MTD makes front-engine riding lawn tractors sold under the MTD name and also builds tractors that are rebranded for other outdoor power equipment lines. For parts on model TMO-33931A, the most accurate way to confirm fit is always the full model number on the ID tag.
Common MTD-made lawn tractor brands
You will often see MTD-built lawn tractors sold under brands such as:
- MTD
- Cub Cadet
- Troy-Bilt
- Yard Machines
- Yard-Man
- Bolens
How to tell if your tractor is MTD-built
Use the identification label on the tractor, then match parts using diagrams for your exact configuration.
- Find the model and serial tag (commonly under the seat, on the frame rail, or near the engine)
- Write down the full model number exactly as shown (example: TMO-33931A)
- Use the model number to select the correct parts list and diagrams
- Match parts by diagram callout and description, not by appearance alone
- Replace missing hardware with the exact fastener type and length listed for the callout
Why the model number matters more than the hood brand
Many MTD-built tractors share similar styling across brands, but belts, deck spindles, brake components, and driveline parts can differ by configuration.
| Identifier you have | What it tells you | Best way to use it |
|---|---|---|
| Brand name on hood | Marketing brand | Use it only as a starting point |
| Model number tag (TMO-33931A) | Exact build/configuration | Use it to choose diagrams and parts |
| Part number on old part | Direct part ID | Cross-check against the model parts list |
Parts examples you might see on TMO-33931A
These are common part types you may run into during repairs; match by diagram callout for your tractor.
- Speed belt 754-0280 for drive speed issues caused by a worn belt
- Sleeve belt 754-0329 when belt sleeves are cracked or missing
- Return brake 732-0264 when brake return action is weak or inconsistent
Why it matters
MTD tractors are frequently rebranded; using the model number prevents ordering the wrong belt, spindle, or brake part and speeds up troubleshooting.
Last updated: February 2026
How do I tell what year my MTD mower is?
For your MTD riding mower model TMO-33931A, the year is identified from the mower’s serial number. On MTD 11-character serial numbers, the 5th character is the last digit of the year it was manufactured; you then use the rest of the tag details to determine the correct decade.
Where to find the model and serial tag
The model/serial tag is on the tractor frame. Common locations include:
- Under the seat pan or seat bracket area
- On a frame rail near the engine compartment
- Near the rear hitch plate or rear frame crossmember
- Under the hood area on the chassis
How to decode the year from the serial number
Use this quick process:
- Write the serial number exactly as shown (letters and numbers)
- Confirm it has 11 characters
- Count from left to right and find the 5th character
- That character equals the last digit of the build year
- Determine the decade by comparing the mower’s features and purchase timeframe
Example decode
| Serial number (example) | 5th character | Year digit | Meaning |
|---|---|---|---|
| 1A2B9C3D4E5F | 9 | 9 | Built in a year ending in 9 |
| 1A2B3C3D4E5F | 3 | 3 | Built in a year ending in 3 |
If your serial number is not 11 characters
MTD used more than one serial-number format. When the serial number format differs, the most reliable way to stay on track for repairs is to match your tractor’s configuration to the parts diagrams and use model-based parts selection for TMO-33931A.
- Match deck and drive layout before ordering belts or pulleys
- Compare steering and brake components to the diagram callouts
- Replace missing hardware with the correct OEM-style fasteners
A common hardware item you may see listed is the MTD lawn tractor screw 710-0599.
Why it matters
The build year helps you select the correct belts, pulleys, spindles, and brake parts for the exact production run, which prevents fit issues and repeat repairs.
Last updated: February 2026
How do I find MTD replacement parts?
For your MTD TMO-33931A front-engine lawn tractor, the fastest way to find the correct replacement parts is to match parts to your exact model number (TMO-33931A), then use the parts list and diagrams to identify the right component and part number before ordering.
Step-by-step: how we recommend finding the right part
- Confirm the model number TMO-33931A on the tractor’s model/serial tag.
- Identify the system you’re repairing (deck, drive, steering, brake, electrical).
- Use the parts list and diagram callouts for MTD TMO-33931A to narrow to the exact item.
- Match the part number on the listing to your need (belt vs pulley vs spindle).
- If you’re replacing hardware, match by type and application (screw, washer, nut) and replace like-for-like.
Common parts on this model (examples)
| Repair need | Example part on this model | What it affects |
|---|---|---|
| Poor drive or slipping | Speed belt 754-0280 | Ground drive speed control |
| Belt wear in certain applications | Sleeve belt 754-0329 | Belt routing and operation (by application) |
| Brake return problems | Return brake 732-0264 | Brake pedal return and braking feel |
| Tire or wheel service | MTD lawn tractor tire 734-0864 | Traction and ride quality |
Tips to avoid ordering the wrong part
- Compare the old part’s stamped numbers, length, and mounting style to the listing.
- Inspect related wear items before you order (for example, belt wear often goes with pulley wear).
- For tire issues, troubleshoot a slow leak before replacing; use how to repair a riding lawn mower tire video.
- For starting symptoms, diagnose first so you replace the right component; use riding lawn mower engine clicks but doesnt turn over video.
Why it matters
MTD tractors often share similar-looking components across different series; using the exact TMO-33931A model match helps ensure belt length, pulley fit, and brake and drive parts match correctly.
Last updated: February 2026
