Relay question

[spiralout]

Not motorcycle related at all, but I figured there were enough here with electrical knowledge I'd ask. I'm in the process of restoring a '94 Tigershark 640cc PWC and need to replace the bilge pump module. I'm wanting to just substitute an automotive relay in it's place but need to know what kind/style to use. This is how the original module works:
4 wires total. One black ground, one white hot that sends power to the pump and two yellow. The yellows are interchangable. One goes inside the electrical box and senses power so that the pump will come on with the engine. The other yellow goes to the pump switch on the bars so that you can run the pump manually with the engine off. Any suggestions as to what relay I can replace the orignal, expensive, out of production module with and what relay connections go where?

[WingAdmin]

Not motorcycle related at all, but I figured there were enough here with electrical knowledge I'd ask. I'm in the process of restoring a '94 Tigershark 640cc PWC and need to replace the bilge pump module. I'm wanting to just substitute an automotive relay in it's place but need to know what kind/style to use. This is how the original module works:
4 wires total. One black ground, one white hot that sends power to the pump and two yellow. The yellows are interchangable. One goes inside the electrical box and senses power so that the pump will come on with the engine. The other yellow goes to the pump switch on the bars so that you can run the pump manually with the engine off. Any suggestions as to what relay I can replace the orignal, expensive, out of production module with and what relay connections go where?

You'll likely need a little more than a relay for this.

First off, where is the power coming from the power the pump? You say you've got two yellow wires, each of which apparently trigger the relay. You've got a ground. Then you have the white hot - is that going TO the pump? Where is the connection to the battery?

Assuming there is a power connection, you could do this with either two relays, or one relay and a diode. You can't just connect the two yellow wires together, because you'll end up back-feeding the ignition and powering up the PWC when you turn the bilge switch on.

[spiralout]

Oops My fault. Power to the pump comes from a fused hot off the battery. The white is ground from the pump. Sorry, I haven't had a whole cup of coffee yet. So the yellows trigger the relay to complete the ground.
Edit: Here's the diagram. Idk if it'll be large enough to see after the forum resize though.

[WingAdmin]

Oops My fault. Power to the pump comes from a fused hot off the battery. The white is ground from the pump. Sorry, I haven't had a whole cup of coffee yet. So the yellows trigger the relay to complete the ground.

Oh OK, so it's switching the ground, not hot.

So you can do this with a standard automotive relay:

Pins 85 and 30 both get connected to ground. The white wire from the pump gets connected to pin 87.

On the yellow wire coming from the ignition, install a diode - I would use one rated for at least 3 amps, and 20 volts (get them at Radio Shack or online). Connect the cathode of the diode (the end with the white stripe) to pin 86 on the relay. The anode of the diode gets connected to the yellow wire coming from the ignition.

The other yellow wire (from the switch) gets connected directly to pin 86.

I'm assuming the yellow wires supply +12V when activated.

I can't see the wiring diagram - it's too tiny!

[spiralout]

Thanks. Looks pretty simple. Any certain part number for the relay? I'll have to get it from a local auto parts supply and the clueless counter girls that they all seem to hire around here instead of someone who actually knows what your talking about will either want a part # or the make and year. And ya, the one clueless about this relay just call the O'Reilly's girls clueless

[WingAdmin]

Any generic automotive style relay will do. They look like this:

[maintainer]

Many properly amperage rated 12V relays will likely work. A relay simply put, is a device that thru the use of a primary or low power source, controls or switches a secondary (think high amperage) line on and off. This a very simplified non-technical definition.