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| | | | Joined: Apr 2008 Posts: 643 'Bolter | | 'Bolter Joined: Apr 2008 Posts: 643 | 58 gmc1/2ton truck with electric fuel pump. Adding a 3 wire oil pressure switch for the fuel pump. everything is done EXCEPT where does the wire go on the ignition switch? Here is the switch terminals : batt , ign1, sol, ign2, acc Ran a wire to the starter; ran a wire to the pump; both with fusible link , third wire goes to the ignition switch BUT which terminal? BATT , IGN1 , SOL , ACC , IGN2  Thanks in advance
Danny
1958 GMC stepside GMC 302 six cylinder 3 speed OD trans
| | | | | Joined: Feb 2004 Posts: 29,783 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,783 | "IGN 1". The IGN 2 terminal is only used during starting to route full battery voltage to the coil and bypass the ballast resistor. Why did you run a wire to the starter? I suppose you could use the "S" terminal of the starter to run the fuel pump during cranking to assure fuel pressure before the oil pressure builds up.
Jerry
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| | | | | Joined: Apr 2008 Posts: 643 'Bolter | | 'Bolter Joined: Apr 2008 Posts: 643 | Well what I read the oil switch is marked S, I , P
S=starter wire
P= fuel pump
I= ignition switch
IGN1 thanks Jerry
Danny
1958 GMC stepside GMC 302 six cylinder 3 speed OD trans
| | | | | Joined: May 2005 Posts: 281 'Bolter | | 'Bolter Joined: May 2005 Posts: 281 | Check your switch connections to see if ign2 is in fact used to bypass the resistor and is only hot during starting. Some switches have ign2 parallel with ign1 to provide a separate 12volt connection that is not electrically connected to the ignition coil when the switch is turned off. If it is hot all the time your switch is on you will be bypassing the ballast resistor all the time.
I have the similar S I P connections on the pressure switch and you are right, the S connects to the starter solenoid to activate the pump during starting before oil pressure builds up. It may connect to either the starter solenoid terminal or to the SOL terminal on your switch. | | | | | Joined: Jan 2013 Posts: 2,234 Moderator: Interiors, Texas Bolters, Name that Part | | Moderator: Interiors, Texas Bolters, Name that Part Joined: Jan 2013 Posts: 2,234 | When I had mine hooked up, I ran a positive off the battery, the negative went through the oil pressure switch and then to the frame. I used the 2 parallel male connections. I never used the 3rd and everything worked great. | | | | | Joined: Apr 2008 Posts: 643 'Bolter | | 'Bolter Joined: Apr 2008 Posts: 643 | Check your switch connections to see if ign2 is in fact used to bypass the resistor and is only hot during starting. Some switches have ign2 parallel with ign1 to provide a separate 12volt connection that is not electrically connected to the ignition coil when the switch is turned off. If it is hot all the time your switch is on you will be bypassing the ballast resistor all the time.
I have the similar S I P connections on the pressure switch and you are right, the S connects to the starter solenoid to activate the pump during starting before oil pressure builds up. It may connect to either the starter solenoid terminal or to the SOL terminal on your switch. There is a jumper between the IGN1 & IGN2....
Danny
1958 GMC stepside GMC 302 six cylinder 3 speed OD trans
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