starter motor blowing fuses

[KCB]

Helping a mate with his px 200, the starter motor keeps blowing the battery fuse.

Starter turns the motor over but as soon as you let go of the button the fuse pops.

Removed every other connection from the Main wiring block under the horncast so only the starter motor is connected so nothing else can be shorting.

Tried a continuity test between the starter live wire and ground and get continuity so I suspect this is the issue and possibly the starter motor is bad. Probably works when you press the starter button as the earth is temporarily disconnected as soon as you let the button go the earth is back and shorts blowing the fuse.

Does this sounds feasible?

Could someone test the continuity between the starter motor live terminal (under the little rubber cap on the starter motor) and the earth screw above the flywheel and post the result?

Thanks

[KCB]

Blimey, the vespa types on this forum aren't very helpful are they lol

Is there no-one with a meter that can test their starter motor to see if it is permanently earthed?


Are there any other vespa forums with more helpful members?

[Tractorman]

Never any experience on vespas but the but I would normally expect the starter to be earthed all the time even when turning. You should the earthing continuity and make sure all earth contacts are good.

[KCB]

Blimey, the vespa types on this forum aren't very helpful are they lol

Is there no-one with a meter that can test their starter motor to see if it is permanently earthed?


Are there any other vespa forums with more helpful members?

When I say permanently earthed, I mean on both terminals from the started motor to the front of the scooter i.e. the terminal on the motor itself and the one on the engine casing both are earthed at the moment.

Surely this isn't correct, I would just like clarification from someone with a Vespa and a meter.

Cheers.

[joeythescooterboy]

Patience is a virtue young man.......... I'm sure a grown up will come along soon and give a decent answer unlike some forums/FB pages where everyone is an "expert" and gives a guess.

[firekdp]

Helping a mate with his px 200, the starter motor keeps blowing the battery fuse.

Starter turns the motor over but as soon as you let go of the button the fuse pops.

Have you sorted this yet?

[KCB]

Nope, didn't get any answers from anyone, mate is saving up to take it to a scooter shop

[firekdp]

You've a PM.

[JETEX]

I'm not familiar with the Vespa starter motor, but it should operate in exactly the same way that a car one does. There should be a thick ' live ' feed from the battery to the motor. Opposite this is an equally thick wire which goes into the motor. There will then be a solenoid either on or near the motor. This in effect, is just a relay. It will have a live and earth to operate it. This causes an electro magnet to jump up an bridge the two heavier terminals which will then feed the starter. The live feed to the solenoid ( known as the energising lead ), is usually the one that is switched by the starter button. If you can find this lead, disconnect it from the solenoid, switch on the ignition and with a piece of wire from the positive terminal on the battery, touch the other end on the solenoid terminal. The starter should spin the engine over. If it then blows the fuse again, the starter is drawing too much current and will have to be repaired or replaced. If it doesn't blow the fuse, the fault is possibly in the starter button or associated wiring. Hope this helps.

[firekdp]

. If it then blows the fuse again, the starter is drawing too much current and will have to be repaired or replaced.

The starter motor, itself, isn't fuse protected, it draws far too much current in normal operation for that small fuse.