electric fuel pump question

Old August 16th, 2009, 01:56 PM
  #1  
Registered User
Thread Starter
 
Join Date: Apr 2009
Posts: 22
electric fuel pump question

Hi guys,
I am hooking up an electric fuel pump to my 72 Cutlass S. It has two wires, one positive, one for ground. My question: where is a good place to hook up the positive wire so that the pump is on when key is turned on?
Thanks ahead of time.
oldjunk is offline  
Old August 17th, 2009, 07:14 AM
  #2  
Moderator
 
Olds64's Avatar
 
Join Date: Jul 2007
Location: Edmond, OK
Posts: 10,953
You need to find 12V ignition. The best place to find that is the fuse box. However, you can also find 12V ignition on the wiper motor.
Olds64 is online now  
Old August 17th, 2009, 09:10 AM
  #3  
Old(s) Fart
 
joe_padavano's Avatar
 
Join Date: Mar 2007
Location: Northern VA
Posts: 31,983
Originally Posted by Olds64 View Post
You need to find 12V ignition. The best place to find that is the fuse box. However, you can also find 12V ignition on the wiper motor.
I would not recommend using the wiper motor as a high current feed for a fuel pump. I would run a fused wire directly from the battery through a relay that is controlled by switched power. I would also install either an oil pressure switch or an inertia switch as a safety measure to prevent continuing to pump fuel in the event of a crash. The inertia switch from a Ford Windstar minivan is common in wrecking yards and works well.
joe_padavano is offline  
Old August 17th, 2009, 11:56 AM
  #4  
Registered User
 
D Appeldorn's Avatar
 
Join Date: Apr 2007
Location: Emmen Drenthe (Netherlands)
Posts: 586
I alway's take a normal 12v ignition wire like those of the radio.
If it goes on of with ignition key. it doesn't need much of power and you can alway's use or mount a second switch as emergency switch ( as we use it with 4x4 challenge also)

it's the same if you mount a hei (needs also 1 12v ignition wire)
mostly i take a wire that is secured with a 10 amps fuse for safety

We also mount a T (splitter) before the pump so that gas can return in the tank if the carb don't ask for more feul. So the in and return is mounted before it goes true the pump. And it can never overflow the carb.
D Appeldorn is offline  
Old August 17th, 2009, 03:38 PM
  #5  
Registered User
 
Join Date: Aug 2008
Location: Iowa
Posts: 1,130
Originally Posted by D Appeldorn View Post
I alway's take a normal 12v ignition wire like those of the radio.
If it goes on of with ignition key. it doesn't need much of power and you can alway's use or mount a second switch as emergency switch ( as we use it with 4x4 challenge also)

it's the same if you mount a hei (needs also 1 12v ignition wire)
mostly i take a wire that is secured with a 10 amps fuse for safety

We also mount a T (splitter) before the pump so that gas can return in the tank if the carb don't ask for more feul. So the in and return is mounted before it goes true the pump. And it can never overflow the carb.
That depends on the pump. Some pumps can't use a return line.
380 Racer is offline  
Old August 17th, 2009, 06:48 PM
  #6  
Registered User
 
gearhead1218's Avatar
 
Join Date: Nov 2008
Location: Palmyra, NY
Posts: 227
Originally Posted by joe_padavano View Post
I would not recommend using the wiper motor as a high current feed for a fuel pump. I would run a fused wire directly from the battery through a relay that is controlled by switched power. I would also install either an oil pressure switch or an inertia switch as a safety measure to prevent continuing to pump fuel in the event of a crash. The inertia switch from a Ford Windstar minivan is common in wrecking yards and works well.
That's the RIGHT way to do it.
Although I did not think of the oil pres. sw. or the inertia switch. I guess I'll be adding it soon to my system. THANKS JOE.

You're also better off running a return style system. You will have a constant flow of cool fuel and more stable pressures.
Attached Images
File Type: jpg
Fuel system7.jpg (117.1 KB, 75 views)
File Type: jpg
Fuel system30001.jpg (64.5 KB, 68 views)
File Type: jpg
Fuel system5.jpg (102.4 KB, 70 views)
gearhead1218 is offline  
Old August 17th, 2009, 08:05 PM
  #7  
Registered User
 
Join Date: Nov 2008
Location: Lehigh Valley Pa
Posts: 695
Originally Posted by joe_padavano View Post
I would not recommend using the wiper motor as a high current feed for a fuel pump. I would run a fused wire directly from the battery through a relay that is controlled by switched power. I would also install either an oil pressure switch or an inertia switch as a safety measure to prevent continuing to pump fuel in the event of a crash. The inertia switch from a Ford Windstar minivan is common in wrecking yards and works well.

This is what I did. On my car atleast there are spare spots on the fuse block that and can slip a connector in for the swtiched power.
The Stickman is offline  
Old August 18th, 2009, 11:38 AM
  #8  
Registered User
 
D Appeldorn's Avatar
 
Join Date: Apr 2007
Location: Emmen Drenthe (Netherlands)
Posts: 586
We also use low presure pumps, high presure for injection type.
Dont know how it works with a 350 or higher but i use it on a 1600 16v and in a 4.2l jeep that runs on liquide gas and petrol. The jeep has a switch to turn between liquide gas or petrol thats the reasen it running with a electric pump.

liquide gas is aboute 40 eurocents and petrol like 95 1,45 euro

do not know if i mount that system on the olds yet

did'nt know there are pumps with return on it, stupid but i never asked for it.
D Appeldorn is offline  
Old August 28th, 2009, 03:59 AM
  #9  
Texas Jim
 
Texas Jim's Avatar
 
Join Date: Aug 2009
Location: Killeen, Texas
Posts: 437
I always use the tank vent line (when doing a car w/ a "factory" vent line) f/ the fuel return and get an appropriate vented tank cap. Hook up the pump w/ a regulator and it works well. It really does make a difference when you feed the carb w/ cooler fuel. And if you're going w/ an electric pump anyway, it's not that much extra work. I did this w/ my '81 'Vette only because the stock mechanical pump is hell to get to. W/ the electric pump, it's a breeze, very convenient and left alittle space where the original pump was-any extra space in that engine compartment is welcomed.
Texas Jim is offline  
Old September 23rd, 2009, 04:34 AM
  #10  
Registered User
 
Mongoose's Avatar
 
Join Date: Aug 2009
Location: Ft. Wayne, IN
Posts: 124
Gearhead1218 I love the pix of your fuel system set up... I'd love to see more.
Mongoose is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
69442
Racing and High Performance
11
May 5th, 2016 12:42 PM
ah64pilot
Racing and High Performance
19
April 9th, 2012 02:55 PM
big mean
Big Blocks
17
December 11th, 2009 06:44 AM
ozzyolds
Small Blocks
2
August 26th, 2008 12:56 PM
Sixoh
Electrical
3
December 18th, 2006 02:07 PM


Thread Tools
Search this Thread
Quick Reply: electric fuel pump question


Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.