Help to choose my starter

[alundra]

Ok, some news...

It seems it isn't the starter, test mine and an another.
I tested many relays (specialy gray relay near battery, controlled for ignition right?).
battery charged and tested

Ok, let me explain my troubles:

2 wires fits on the starter: one black/yellow little size ordered by ignition, one black/red normal size which go to the battery.

When the plugs are on the starter (metal shield of starter on a ground of the car), when i join together the 2 wires said upper, by an external wire, starter work perfectly (gear exit and turn), but when i turn the key only nothing appear.

I know that my english isn't good, but in my mind it's the black/yellow wire that is in fault because the continuity of the "normal" wire exist, no doubt about it.

The solution i expect to install a start button relay (how many Amperes?) to command the ignition.

Do you have any hint or help about my starter trouble?

Cheers.