What Is Lawn-Boy Performance 2-Cycle Oil? (Mix Ratio Chart)
Lawn-Boy Performance 2-Cycle Oil is oil made to mix with gasoline for compatible two-stroke engines. The correct fuel-to-oil ratio depends on your mower’s model and the oil label, so do not assume every Lawn-Boy uses 50:1. If your manual calls for 50:1, mix 2.6 fluid ounces of oil with each US gallon of gasoline.
What if your mower manual says “2-cycle oil,” but you are not sure how much to add? The ratio matters: too little oil can damage engine parts, while too much can cause smoke and poor running. First identify your exact mower and engine, then use its instructions to choose the right mix.
What Is Lawn-Boy Performance 2-Cycle Oil? Mix Ratio Chart
Lawn-Boy Performance 2-Cycle Oil is premix oil for compatible two-stroke engines. “Premix” means you combine the oil with gasoline before fueling the engine. The oil helps lubricate engine parts as the fuel burns. Its name alone does not tell you the correct ratio for every mower.
A two-stroke engine does not use a separate oil-filled crankcase in the same way as a four-stroke engine. Instead, the engine uses oil mixed with its fuel for lubrication. This is why the right oil and ratio are essential.
The word “Performance” is part of the product name, not a universal mixing instruction. Check the oil bottle’s label and your mower’s manual. Use the ratio specified for your exact model. If they appear to conflict, contact the manufacturer or an authorized service provider before running the mower.
50:1 mix chart
A 50:1 ratio means 50 parts gasoline to 1 part oil by volume. Use this chart only if the mower’s manual or oil label specifies 50:1. The amounts below are measured against the gasoline volume.
| Gasoline | 2-cycle oil at 50:1 |
|---|---|
| 1 US gallon | 2.6 US fl oz |
| 2 US gallons | 5.1 US fl oz |
| 2.5 US gallons | 6.4 US fl oz |
| 5 US gallons | 12.8 US fl oz |
| 1 liter | 20 mL |
| 5 liters | 100 mL |
Other ratios require different amounts of oil. These common examples are for use only when the mower’s instructions call for them.
| Specified ratio | Oil per US gallon of gasoline |
|---|---|
| 32:1 | 4.0 US fl oz |
| 40:1 | 3.2 US fl oz |
| 50:1 | 2.6 US fl oz |
The chart is not a substitute for the manual. Confirm the ratio first, then measure by volume with a graduated container. Do not estimate by eye.
Identify the Engine, Confirm the Mix Ratio & Prepare Safely
Before mixing fuel, confirm that your mower has a two-stroke engine and find the ratio required for that model. The manual and engine or mower label can also identify fuel-grade and ethanol limits. Prepare the fuel outdoors, away from ignition sources, with eye protection and fuel-resistant gloves.
Start with the model number, not the oil bottle. Find the mower’s model label and look up the matching manual. Check the manual for these details:
- Whether the engine is two-stroke or four-stroke
- The required gasoline-to-oil ratio
- The permitted gasoline grade and ethanol content
- Any oil type or compatibility requirements
A four-stroke engine uses a separate crankcase oil system. Do not put two-cycle premix oil in that system, and do not use four-cycle crankcase oil as a substitute for two-cycle premix oil.
If you cannot confirm the engine type or ratio, do not run the mower yet. A generic chart cannot identify the needs of an unknown model. I use the model number as the first check because it avoids a common mistake: choosing a ratio based only on a bottle or a chart found online.
Prepare in a well-ventilated outdoor area, away from flames, sparks, and other ignition sources. Wear eye protection and fuel-resistant gloves. Use an approved fuel container that is clean and suitable for gasoline. Keep the container closed when you are not adding fuel.
Mix Fuel and Operate the Lawn-Boy Mower
To make the correct mix, measure the gasoline and oil separately, then combine them in an approved fuel container. Add only the amount of oil called for by the confirmed ratio. Close the container and mix thoroughly before fueling the mower.
Follow these steps:
- Check the manual for the specified ratio and fuel requirements.
- Measure the gasoline amount you plan to use.
- Calculate and measure the matching oil amount by volume.
- Put both in the approved fuel container, close it, and mix thoroughly.
- Label the container with the ratio and the date you mixed it.
For example, if the manual specifies 50:1 and you measure 2 US gallons of gasoline, add 5.1 US fluid ounces of oil. If the manual specifies 40:1, the amount for that same gasoline volume is 6.4 fluid ounces. The gasoline amount stays the same; the oil amount changes with the ratio.
These examples are calculations, not claims about a particular Lawn-Boy mower. They show why identifying the model comes before measuring. If you put in too little oil, do not run the engine. If you are unsure how to correct a mix, check the manual or get qualified service advice. Do not add extra oil without instructions. Too much oil can also cause smoke, spark-plug fouling, and poor running.
Fuel the mower outdoors with the engine off and cool. Wipe up any spilled fuel before starting. Start and operate the mower as the manual directs. Stop the engine if you notice abnormal noise, a loss of power, or signs of overheating. Do not keep running it to “see if it clears.”
Common mix-up: using the wrong ratio
A frequent point of confusion is treating 50:1 as the standard for every two-stroke mower. It is not. Another is confusing the ratio printed on an oil label with the mower maker’s instructions. Check both before mixing, and do not assume one overrules the other.
The key step is simple: match the ratio to the exact engine, measure both liquids, and mix them in a separate container. This gives you a chance to check the fuel before it reaches the mower.
Clean, Inspect & Maintain the Two-Cycle Engine
Correct fuel mix is only one part of routine care. After mowing, stop the engine and let it cool before cleaning or inspection. Follow the manual’s maintenance steps, including instructions for keeping the cooling-air passages and cutting deck clear of grass.
Grass that blocks cooling-air passages can interfere with airflow. Clear grass from those areas and the cutting deck as directed in the manual. Do not clean near a hot engine, and keep hands and tools away from moving parts.
If the mower runs poorly, do not assume the ratio is the cause. Check that you used the right mix, then refer to the manual’s troubleshooting section. Stop using the mower if it makes abnormal noises, loses power, or seems to overheat. A suspected lubrication problem can damage the piston or cylinder, so avoid repeated test runs.
A wrong or insufficient oil ratio can cause scuffing, where moving engine surfaces rub and wear, or seizure, where parts can no longer move as they should. Too much oil can also cause problems, including smoke, fouled spark plugs, and poor running. If you do not know what is in the tank, do not try to fix the mix by guessing. Use the manual’s guidance or ask a qualified service provider.
Store Mixed Fuel and Prepare for the Off-Season
Mixed fuel needs suitable storage and handling. Follow the mower and fuel-container instructions for leftover fuel, and do not rely on a general storage period. Fuel needs can vary with the product and conditions, so use the manual’s guidance when storing fuel or preparing the mower for a long break.
Keep fuel in an approved, closed container, labeled with its ratio and mixing date. Store it as required by the container and fuel instructions, away from heat and ignition sources. Do not use fuel that has been stored beyond the period allowed by the product or mower instructions.
Before seasonal storage, follow the mower manual’s steps for the fuel system. Instructions may differ by model, so do not assume that one storage method fits every Lawn-Boy mower. If you are unsure what to do with leftover mixed fuel, check the manual and local fuel-disposal rules. Do not pour fuel onto the ground or into a drain.
Frequently Asked Questions
These short answers cover common questions about Lawn-Boy two-cycle oil and fuel mixing. Always check the exact mower manual before choosing a ratio or fuel type. If the model or instructions are unclear, pause before operating the engine.
What is Lawn-Boy Performance 2-Cycle Oil used for?
It is premix oil for compatible two-stroke engines. Mix it with gasoline at the ratio specified for the engine.
Is Lawn-Boy Performance 2-Cycle Oil always 50:1?
No. Use 50:1 only when the mower manual or oil label specifies it. Lawn-Boy engine requirements can vary by model.
How much oil goes into one gallon of gas at 50:1?
Use 2.6 US fluid ounces of oil for one US gallon of gasoline, but only if the engine calls for 50:1.
How much oil is needed for 5 liters of gas at 50:1?
Use 100 milliliters of oil for 5 liters of gasoline when the engine specifies a 50:1 ratio.
Can I use four-cycle oil instead?
No. Do not substitute four-cycle crankcase oil for two-cycle premix oil. Confirm your engine type and use the oil required by its manual.
Can I run a two-stroke mower on straight gasoline?
No. Do not run straight gasoline in a two-stroke engine that requires premix. The engine needs the specified oil-and-gas mixture for lubrication.
What if I do not know my Lawn-Boy’s mix ratio?
Find the mower model number and check its manual. Do not operate it until you confirm the engine type and required ratio.
Can I add extra oil to be safe?
No. Extra oil is not a safe substitute for the correct ratio. It can cause smoke, spark-plug fouling, and poor running.
Should I mix the oil directly in the mower’s tank?
Use an approved fuel container to measure and mix the gasoline and oil first. Then fuel the mower outdoors with the engine off and cool.
What should I do if I mixed the wrong ratio?
Do not start or run the mower. Check the manual for direction or contact a qualified service provider rather than guessing at a correction.
(This article was written by one of our staff writers, Evan Bradley. Visit our Meet the Team page.)
