12v. switched source

[dcoop46]

Where is the best place to pick up a 12v. switched source for electric fans & fuel pump.  I was thinking at the of tapping off of the white/blue wire at the voltage reg. plug.  Doing the MSA plug & alt. upgrade also.  Diagram show this to be a 12v. switched circuit.  Help greatly appreciated.

[SteveJ]

Post the year of your car in your post. The wiring will vary depending upon the year of your car.

[dcoop46]

Sorry it is a '73.  MSA said that I needed to wire the fuel pump separately thru a 12v. switched circuit.  I am in the process of the alt. upgrade, radiator upgrade, Maxi-fuse upgrade, & rewiring the fuel pump.

[SteveJ]

So do you have a mechanical fuel pump? You should unless you have a later head that doesn't have the port. Are you running SUs? If so, you don't need the electric fuel pump. You could bypass it. That's my plan for my 73.

 

Why are you doing a Maxifuse conversion? You only have the one fusible link by the starter.

[dcoop46]

Yes, I have a mechanical pump and the electric.  I have dual Webers & had read that the mechanical would bogg down.  Doing the maxifuse to upgrade from old wiring.  That would also give me fused output for accessories.  Just trying to bring things up to date.  I really appreciate all of you help & advice.  Been a while since I worked on a Z & there are so many upgrades to modernize.  I was thinking of getting a switched circuit from the regulator plug, + side of the coil, or tapping into the wire from the key.  Wondering which might be best?  Thanks again for your help & patience with a 68 yr. old that hasn't done mechanics in a while.  Trying to come up to speed.

[Zed Head]

From what I've read, some of the electric fans pull a lot of amps.  You'll probably need a dedicated wire and relay for it.

[SteveJ]

More than just that, I would recommend a thermostat control. Using switched power is not that important for the thermostat circuit. I would run a circuit with the thermostat to operate the coil of the relay. Then at least a 10 gauge wire for the power to the fan. All circuits appropriately fused.

[dcoop46]

I have the appropriate wiring harnesses to do the fans & fuel pump.  They have the circuit breakers & fuses with instructions( a necessity).  As always, the more I look, the more I find.  The PO's mechanic wasn't much of one.  That's the challenge of these older cars.  Drove a '38 Chevy for years.  Used to live in Kennesaw.  Thanks for all you help Steve.

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