Small Engine Technology:
Troubleshooting, Repair, Service &
Maintenance Questions and Answers
Latest Version Already Passed
What is one common reason a small engine won't start after being in storage for months?
✔✔ Old fuel has degraded and clogged the carburetor.
What should you check if a small engine is hard to start but runs fine once warm?
✔✔ The choke may not be working properly during cold starts.
Why might an engine overheat even with proper oil levels?
✔✔ Cooling fins may be clogged with dirt or debris.
What could be the cause of black smoke coming from the exhaust?
✔✔ The air-fuel mixture is too rich due to a dirty air filter or misadjusted carburetor.
What maintenance task helps ensure proper spark in a small engine?
✔✔ Regularly cleaning and gapping the spark plug.
1
, What should be done if the engine runs roughly at idle but smooths out at high speed?
✔✔ The idle jet in the carburetor may be partially clogged.
Why is it important to drain fuel from a small engine before long-term storage?
✔✔ To prevent fuel degradation and gum buildup in the carburetor.
What is the most likely cause of a lawnmower engine stalling when the blades are engaged?
✔✔ A faulty safety switch or overloaded engine.
What should be checked if a small engine won't crank at all when the key is turned?
✔✔ The battery or starter solenoid could be faulty.
What is a sign that the valve clearance needs adjustment in a four-stroke engine?
✔✔ Tapping or clicking noises from the engine during operation.
What should be done if the engine surges up and down at idle?
✔✔ The governor spring might be loose or the carburetor needs adjustment.
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Troubleshooting, Repair, Service &
Maintenance Questions and Answers
Latest Version Already Passed
What is one common reason a small engine won't start after being in storage for months?
✔✔ Old fuel has degraded and clogged the carburetor.
What should you check if a small engine is hard to start but runs fine once warm?
✔✔ The choke may not be working properly during cold starts.
Why might an engine overheat even with proper oil levels?
✔✔ Cooling fins may be clogged with dirt or debris.
What could be the cause of black smoke coming from the exhaust?
✔✔ The air-fuel mixture is too rich due to a dirty air filter or misadjusted carburetor.
What maintenance task helps ensure proper spark in a small engine?
✔✔ Regularly cleaning and gapping the spark plug.
1
, What should be done if the engine runs roughly at idle but smooths out at high speed?
✔✔ The idle jet in the carburetor may be partially clogged.
Why is it important to drain fuel from a small engine before long-term storage?
✔✔ To prevent fuel degradation and gum buildup in the carburetor.
What is the most likely cause of a lawnmower engine stalling when the blades are engaged?
✔✔ A faulty safety switch or overloaded engine.
What should be checked if a small engine won't crank at all when the key is turned?
✔✔ The battery or starter solenoid could be faulty.
What is a sign that the valve clearance needs adjustment in a four-stroke engine?
✔✔ Tapping or clicking noises from the engine during operation.
What should be done if the engine surges up and down at idle?
✔✔ The governor spring might be loose or the carburetor needs adjustment.
2
