12V to new water pump.

[adonh]

I am replacing the water pump in my 1976 A/S. The old one has not worked in years. A while back I removed the old control panel that had the gauges for the holding tanks and the switch for the water pump. So now I have no power to the from the power and group wires that were connect to the old pump. How can I rewire to provide power and then install a separate new switch for the pump.

Thanks

Don

[Zeppelinium]

Hmmm, no photos, so I'll guess your '76 looks a lot like my 75'. If you didn't cut the control panel wires off right at the interior skin, you should be able to hook up a switch to the old pump wire. There would also have been a "hot" 12 volt wire in that bundle. So, hot 12 volts to switch, pump wire from switch to pump, ground the other pump wire.

The Converter and pump are both under the sink, right? If your wires are all cut short, you could run a wire from the fuse block to a switch, back to the pump, then ground the other pump wire to the frame. This is a DC motor so it's important to get the polarity of the wires right or the motor will run backwards.

You could put the switch in a convenient place under the sink, but visible, so you wouldn't have to run wires up to the upper cabinet.

Zep

[adonh]

Originally Posted by Zeppelinium

If you didn't cut the control panel wires off right at the interior skin, you should be able to hook up a switch to the old pump wire. There would also have been a "hot" 12 volt wire in that bundle. So, hot 12 volts to switch, pump wire from switch to pump, ground the other pump wire. Zep

No I did not cut the wires. I just unplugged the big connector behind the control panel. So everything is still intact. There was a orange wire from the switch to the red (hot) wire on the pump. The hot feed to the switch was a common blue wire that provided 12v to the light and other gauges in the control panel. The ground going to the pump is a white wire to the black ground on the pump.

I can see the blue wire that going behind the kin up to the control panel so I guess a switch between this wire and the red pump wire and use the existing ground should work. Right.

Thanks Zep, let me know if I am on the right track.

Don

[Zeppelinium]

Originally Posted by adonh

...I can see the blue wire that going behind the kin up to the control panel so I guess a switch between this wire and the red pump wire and use the existing ground should work. ... let me know if I am on the right track. Don

You are on exactly the track that I had envisioned. You could just touch the wires together to see if the pump runs (then you'll know you got it right), but be careful. When you pull them apart, the voltage will jump right at that point to some high levels--won't hurt you (unless it makes you break an arm when you flinch!) but you won't like it. All you have to do is hold the wires about an inch from the ends and you'll be fine.

Zep

[adonh]

I found a hot and ground wire that was not hooked to anything back behind the stove. I think it had once been connected to the furnace, which I took out. It has power so I will use this one sine it is right there where I need it.