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Fuel pump cut-off switch - HELP with simple question!

  • Thread starter Thread starter MikeR351w
  • Start date Start date May 4, 2010

MikeR351w

Founding Member
Oct 8, 2001
207
0
16
Wisconsin
May 4, 2010
#1
  • May 4, 2010
  • #1
I have a 93 LX 5.0L. I park it in a bad area. I recently wired in a fuel pump cut-off switch about two weeks ago. I wired it in between the positive (12v) going to the relay.

This morning, the fuel pump was stuck in the priming mode and would not shut off. I turned the pump off by using my new switch. I later found out the relay was fried and replaced it with no problems. Works great again, but...

Heres my question:

I used a 30amp 3-prong switch for the fuel pump shut off switch. I grounded one end as shown in the diagram that came with the switch. The other two ends simply connected to the On and Off. Would this switch fry my relay??????????? THANKS ELECTRICAL GURUS!!!!
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
May 4, 2010
#2
  • May 4, 2010
  • #2
Ground prong is just for the toggle switch bulb to light up. That being said, those switch's( depending on which one you got) are usually not made to handle a lot of amp. So they fry easily. Or melt should I say. I say the relay was just a coincidence. Its also better to cut the pumps relay ground off with a switch than to cut the power off. Safer this way, and way easier on the toggle switch.
 

MikeR351w

Founding Member
Oct 8, 2001
207
0
16
Wisconsin
May 4, 2010
#3
  • May 4, 2010
  • #3
Great! Thanks for the info. I am now using a 20 amp switch. How much amperage goes through the switch??? I am guessing not more than 10 amps for the pump..
 
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