Temporary Loss of Power By bmizes (Read 794 times)

[bmizes]

My scooter had been sitting in the garage for a couple weeks because of the cold. On Sunday, we got up to 50 so I decided to take it out for a spin. I had been riding for about 50 minutes on city streets with no problems. Then, at a stop, when I turned the throttle to go, nothing happened. It just kept idling but there was no power. I figured I'd have to get it towed, so I turned it off and pulled it to the curb. Just on a whim, I decided to start it up again, so I started it and everything worked again. I rode it home without any further problems. Any idea what could have caused this sudden loss of all power but then would have allowed it to work again normally after just turning off the ignition and restarting? I'm hesitant to take it out again without identifying the problem. Thanks.

[kz1000st]

Crud in the carburetor. It clogged the main jet or pilot jet and fell off when you shut down. Seafoam (1 oz. per gallon) for the next bunch of gas fill ups.

[mike6736]

Hard to say as you said it was an even idle even when given gas...

Magoo

[Alleyoop]

I would say crud in the main jet if it stayed idling that is off the PILOT JET. But I would think it would have made a BOGGGGGGGGG sound when you opened the throttle to get going which was just sucking in air and no fuel.
Alleyoop

[bmizes]

Well I tried the seafoam and had no problems the next couple short trips I made. I then had a longer 45 minute ride last week and this time it started losing power when going up a hill at the end of the ride. It started revving and then decelerating until the engine finally quit. I turned it off, waited a minute or two, and after a couple tries it started up again and ran fine to get home. Once it warms up again outside (it's 10F today) I'm going to change the spark plug and fuel filter to see if the spark plug is having problems as it heats up or the filter is clogged. I've also heard that many of the Chinese scooters have vacuum problems that can cause this. In fact, when my scooter came from Valley Scooters, they recommended drilling a hole in the gas cap to prevent vacuum problems. I didn't do this, but perhaps that's something i should try as well. Anyone have any thoughts on this? Thanks.

Barry

[Alleyoop]

That sounds like lack of fuel, when the rpms rise and drop like that it is running lean. Have you checked your Fuel Filter, also when was the last time you adjusted your valves. It appears you usually have the problem after the motor is nice and hot which would keep the exhaust open a little and not sealing and the motor would loose compression. When the motor looses compression it creates less suction and that would not allow enough vacuum to open the PETCOCK diaphragm to allow fuel to flow to fill the carb bowl.

So I would First adjust the valves and at the same time verify that your fuel filter is clean and not black inside.
Alleyoop

[nctrooper1072]

I'd do .006 on that exhaust valve and .005 on the intake.. The EX valve tends to stretch.However Ive seen intake valves do the same.. U cant get a good carb adjustment unless those valves are right.. U can also do it by feel.. but would'nt try it if ur new to mechanics.. Just Sayin'