Scooter Intermittent Starting Problem By des2105 (Read 3,293 times)

[des2105]

I have a “run of the mill” 50cc Chinese scooter that has developed a problem. It is intermittent – sometimes a few minutes and sometimes as much as a month.

When I turn the ignition switch to on in prep for starting, the first tip off that the problem has returned is that the dashboard lights and head lights will not display nor will the fuel gauge work. Then when I attempt to start the engine, the push button is dead. The scooter will kick start and the dashboard lights as well as the headlights work. The fuel gauge works but only as the engine is revved – at idle it shows no gas.

My battery is fully charged and there is at least a half tank of gas at all times. I have exchanged the ignition switch with another used one but the problem persists. It can work normally for a while and then after shut off and parked for a while the problem starts up again. The reverse is also true. I can kick start the scooter; ride it for a while; park it and when I turn the key to run, everything works fine.

Any ideas as to where to start looking?

[Bashan]

The dash, fuel gauge and starting circuit run off of the black wire that comes off of your ignition switch. It sounds like you have a bad ground that is affecting that wire. Here's a generic diagram, you can trace out how the black runs:

You will need to get your multi out and check continuity on several of the green ground wires to frame. Check, at least, the ignition switch ground, the brake light ground, and the battery ground. Check your fuse too, it obviously is still intact but make sure the connections are tight. Check for corrosion on all the components your testing. Humidity can make a connection come and go where corrosion is present.

[gatekeeper]

My money is on the fused line somewhere, or the fuse itself. If it is the original style and original holder I would replace that setup with a blade type holder and fuse. Could be intermittently losing contact at the fuse holder connections.

[tvnacman]

Aug 10, 2014 16:35:19 GMT -6 gatekeeper said:

My money is on the fused line somewhere, or the fuse itself. If it is the original style and original holder I would replace that setup with a blade type holder and fuse. Could be intermittently losing contact at the fuse holder connections.

I would check this out too .

John

[Alleyoop]

Sounds like the battery is drained after a while unless it gets charged up after he rides it and parks it then he can turn the key on and the battery has enough juice to light it up. So It may be a bad battery that will not hold a charge or something is draining the battery.
Alleyoop

[des2105]

Thank you one and all for the good tips. I also noticed this evening that the break lights work only for the rear break but not for the front. That's following a kick start road trip of about 3 miles. I will do a continuity and corrosion check tomorrow. Thanks again.

[Alleyoop]

Breaks lights only work when you squeeze the breaks and ONLY AT THE REAR there are no breaks lights in front. Do you mean your headlights do not work?
Alleyoop

[gatekeeper]

I think he means that his brake light only comes on when he squeezes the rear brake handle but it does not come on when he squeezes the front brake handle.