Q: Moped Engine Question

asked by on

Good Day,

This should be very easy for you guys.

It's regarding my Tomos 49cc (2 cycle) moped engine. Moped had to sit awhile because I messed up the clutch. So a year later I replaced the clutch and then it wouldn't start.

When it does start after a long rest period - It idles kind of high gives VERY SMOKEY and thick exhaust (some in liquid form) - then shuts off. And after that it won't even crank on again. That's it..


Hi There, It sounds like your moped engine is fouling the spark plug as a result of a a rich oil/fuel mixture. As you know, 2 cycle engines mix fuel and oil together in the fuel tank which is run through the motor. The oil in the fuel helps to lubricate and cool the motor, however these types of engines are prone to fouling spark plugs when too much oil ends up on the electrode of the spark plug, which prohibits the plug from producing the proper spark to ignite the fuel. I would suggest removing the spark plug to see if it is covered in oil. After sitting for a year, it may also need to have the carburetor tuned up or adjusted.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  1. Home
  2. Questions
  3. Moped Engine Question

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...