elec fuel pump with relay

[dougs bs23]

Getting ready to install an electric fuel pump and relay and eliminate the mechanical pump.  Relay instructions say connect 12v to battery but, would it not be better to connect to a source when the key is on? and not have a constant source to the relay?  What/where would a good "key on" source could i use? This is a 4 wire relay and one wire will be a kill switch.  Or am i just over thinking this?

[dodj]

Has to be ignition 'on' position. Otherwise it would never stop., and you would go through a lot of batteries....

[HP_Cuda]

Starter relay I believe is where a good deal of folks hook up to.

[jimmycuda71]

The relay takes two 12 volt sources. The heavy guage wire will go directly to the battery. The other will go to a 12 volt switched source that goes on and off with the key. Make sure that it stays hot when the key is in the start position. It is what trips the relay to send voltage to the pump. When the key is turned off there is no draw on the battery.

[dougs bs23]

so heres the way I'm thinking about doing this.  Blue to battery side of starter relay, yellow as shown, Black to run side of ig switch as shown in my service manual wire Q2 12 bk which is on the run side of ig switch feeding acc side of fuse block, fuses 6,7 &8 to a toggle switch ( killing power to relay (as a theft prevention measure).
Ideas?  comments?

[67vertman]

That is how I ran mine, works great!