57 big twin blows 30 amp fuse

[lymanboat15]

Well I have another motor 1957 35 bigtwin electric start when I hook up the battery the 30 amp fuse in the box blows I have disconnected the amp gauge and as soon as I touch it to the start switch the fuse blows .Can there be a short in the amp meter the boat has been sitting since 94 the starter works fine. I also have cleaned all the connections.

 

[JDusza]

Re: 57 big twin blows 30 amp fuse

Sounds like a short in the gauge circuit. Maybe not the gauge itself. Check the harnessing for cracks and bite marks.
J

 

[F_R]

Re: 57 big twin blows 30 amp fuse

It is either wired wrong, or there is a short someplace. You will have to obtain a wiring diagram and check out the circuit till you find the trouble. Do you have any electrical knowledge and know how to do it?

BTW, there should be no fuse nor ammeter unless you have the optional generator kit. Do you? And it is supposed to be a 20 amp fuse.

It would be extremely unusual for the ammeter to have a short. Almost unheard of, in fact.

EDIT: Come to think of it, the 20A fuse isn't even in the charging or ignition circuit. It is in the accessory Power Take-off circuit. All the more reason to suspect it is wired wrong.

 

[lymanboat15]

Re: 57 big twin blows 30 amp fuse

Thanks for the wiring diagram everything appears to be wired right there were some cracked wires taped them still blows fuse what is the simplest way to check the cable for shorts . The electric choke works with the amp gauge disconnected.

 

[F_R]

Re: 57 big twin blows 30 amp fuse

Refer to the wiring diagram. Is the ammeter connected EXACTLY as shown? IF it is, my guess is the short is in the charging circuit inside the junction box. Back to the previous statement, the fuse is not in the charging circuit, but it is in the accessory feed circuit. That accessory terminal may be where the short is. Try disconnecting the brown wire from the accessory terminal.

Anyhoo, with the brown wire disconnected from the ammeter, the choke and starter should both function---IF the ammeter is connected exactly as shown. Do they both function that way?