Common Engine Problems You Can DIY

Most of the time, when you pull the cord your engine starts reliably and you are off getting your work done, but occasionally things don’t always go as planned. The good news is you can troubleshoot many small engine issues yourself. All you need are basic tools and a can-do attitude. And if you need help, we’ve got your back with the support you need.

In most cases a quick clean or tune up will be just the fix, but before you roll your sleeves up, make sure to read up in your engine and equipment manuals. Additionally, always remove and disconnect the spark plug before working on your engine.

Lawn Mower Won’t Start? Is Your Engine Stalling, Surging or Running Rough?

1. Check Your Fuel: Is Your Fuel Fresh?
Gasoline can begin to degrade in as little as 30 days after it’s pumped, so make sure you have a full tank of fresh, clean fuel. You’ll also want to make sure you are using fuel E10 or less, E15 or E85 is actually illegal to use in outdoor power equipment. If you aren’t sure, drain the gas and replace with fresh gas and add fuel stabilizer.

2. Fuel Stabilizer: Did You Add Protection to Your Engine?
A dirty carburetor can be caused by stale fuel and cause poor engine performance or starting problems because it regulates air and fuel movement. Here is more info for cleaning carburetors and rebuilding carburetors. A fuel stabilizer like Briggs & Stratton’s Advanced Formula Fuel Treatment & Stabilizer will also help keep your fuel fresh and carburetor clean.

3. Check the Spark Plug: Is Your Spark Plug Dirty or Fouled?
Spark plugs should be replaced every season or 25 hours of use and won’t function properly if dirty or disconnected. Follow this guide to check or replace spark plugs.

4. Check the Air Filter: Is the Air Filter Dirty or Plugged?
Depending on how frequently you mow, we recommend cleaning or replacing the air filter every 25 hours or every season.

5. Check Your Oil: Is Your Oil Fresh?
Check the oil level and appearance (oil should be translucent, not black) and change it every 25 hours of use or every season.

Lawn Mower Engine is Smoking?

A smoking engine is a sign of various things, but fortunately the color of the smoke is a good indicator of what the problem is:

1. White or blue smoke means your engine is burning oil.

2. Black smoke could be caused by a dirty air filter, flooded carburetor and/or bad fuel. Check the carburetor, drain the gas and replace with fresh gas and add fuel stabilizer and clean or replace the air filter if it’s dirty or plugged.

Lawn Mower Engine is Overheating?

1. Is the engine dirty?
Clean and remove debris from your engine. If there are grass clippings in the shroud remove by hand, or if there are grass clippings built up underneath your deck clear off them with a hose or pressure washer.

2. Is the oil level low?
Check or change the oil and add if necessary. We recommend changing the oil every season during your annual tune up.

3. Are any shrouds or cooling fins missing or broken?
Install new parts if needed and reference your operator’s manual or visit your local authorized Briggs & Stratton dealer.

4. Is there a leaky gasket?
Check and replace the gasket with this guide.

5. Is the fuel tank vent or fuel tank screen plugged?
Clean the fuel tank vent and screen.

When it comes to common small engine problems, you’d be surprised how much you’re capable of fixing yourself. For more details or information, check out our FAQ page. If you’d like an extra professional opinion reach out to us at Briggs & Stratton or visit your local dealer.

NOTICE: Customer service questions are not monitored via the blog. If you need assistance with your Briggs & Stratton engine or power equipment, please contact our Answer Center or post your question to our User Community.