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Under-hood switched 12V source?

  • Thread starter Thread starter Dingleweed
  • Start date Start date Apr 28, 2006

Dingleweed

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Dec 28, 2004
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Apr 28, 2006
#1
  • Apr 28, 2006
  • #1
I am wiring up the relay for my electric water pump. I need a ignition switched 12 V source under the hood.

Anyone know of a switched 12 V source under the hood that I can tap into? Please post pics, or be as specific as possible.

Thanks!
 

DropTopPony

Noob Slayer
Founding Member
Aug 13, 2002
2,570
3
48
south jersey
Apr 28, 2006
#2
  • Apr 28, 2006
  • #2
don't you have a test light or volt meter to find one?
 

Dingleweed

New Member
Dec 28, 2004
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Apr 28, 2006
#3
  • Apr 28, 2006
  • #3
I had one, but couldn't find it today. I'll probably go buy another one tomorrow...
 

Dorsai

New Member
Aug 13, 2005
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Connecticut
Apr 29, 2006
#4
  • Apr 29, 2006
  • #4
Your better off putting in a dedicated line on something like a water pump due to the current draw. Tapping into an exsisting line might pop a fuse at the wrong time if whatever is supposed to be on the line originaly decides to draw full power. Just buy a relay and run a fused link right to the battery so you wont have to worry about it going out on you...which would be bad on the water pump...

This site has what you'd need to run a dedicated power feed from the battery. Call/email them and tell them you want to wire an ignition switched relay and line for the water pump. They should be able to size the wire, relay and connectors for you.

http://order.waytekwire.com/CGI-BIN/LANSAWEB?WEBEVENT+L0B48D3406C8686004055022+M37+ENG
 

Dingleweed

New Member
Dec 28, 2004
20
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0
Apr 29, 2006
#5
  • Apr 29, 2006
  • #5
Dorsai said:
Your better off putting in a dedicated line on something like a water pump due to the current draw. Tapping into an exsisting line might pop a fuse at the wrong time if whatever is supposed to be on the line originaly decides to draw full power. Just buy a relay and run a fused link right to the battery so you wont have to worry about it going out on you...which would be bad on the water pump...

This site has what you'd need to run a dedicated power feed from the battery. Call/email them and tell them you want to wire an ignition switched relay and line for the water pump. They should be able to size the wire, relay and connectors for you.

http://order.waytekwire.com/CGI-BIN/LANSAWEB?WEBEVENT+L0B48D3406C8686004055022+M37+ENG
Click to expand...

I already have the relay kit from Meziere . When the realy is activated, the electric water pump draws its current straight from the alternator output post, and the ground goes straight to ground. I just needed a 12 V signal to activate the relay (very small current draw).

The source that I found after looking at the wiring diagram for my car is the red wire off of the MAF. The red wire off of the MAF is the same switched source that drives a bunch of stuff on the engine (MAF, EGR, IAC, etc.)

I started it up, and after burping the coolant system, it reached operating temp and just stayed there as it should
 

Dorsai

New Member
Aug 13, 2005
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Connecticut
Apr 29, 2006
#6
  • Apr 29, 2006
  • #6
Good job, I probably should have asked if you had a complete relay kit....
 

Miles

Founding Member
Aug 14, 2001
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Burlington, ON
Apr 29, 2006
#7
  • Apr 29, 2006
  • #7
Why did you decide to get an electric water pump? How much hp do you gain?
 

Dingleweed

New Member
Dec 28, 2004
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0
0
Apr 29, 2006
#8
  • Apr 29, 2006
  • #8
Miles said:
Why did you decide to get an electric water pump? How much hp do you gain?
Click to expand...

Because I am running out of bolt-ons and getting desperate for any amount of additional power to the wheels

Meziere claims 11 to 14 WHP, but other Mach 1 guys say the 4 valves gain about 7 to 10 WHP. That's just on the verge of being able to tell the difference... Driving around it did feel just a teensy tad bit more peppy in the upper rpms.
 

Miles

Founding Member
Aug 14, 2001
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0
Burlington, ON
Apr 29, 2006
#9
  • Apr 29, 2006
  • #9
Dingleweed said:
Because I am running out of bolt-ons and getting desperate for any amount of additional power to the wheels
Click to expand...

I'll be there soon enough, that's why I'm asking So install was easy?
 

Dingleweed

New Member
Dec 28, 2004
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Apr 30, 2006
#10
  • Apr 30, 2006
  • #10
Miles said:
I'll be there soon enough, that's why I'm asking So install was easy?
Click to expand...

Yeah, the install was very straight forward:

Before you start have a 6mm ball end allen wrench. (the kind that can tighten an allen bolt at a slight angle). If you have underdrive pulleys you will need a shorter belt (2.5" shorter, I used a Gatorback #4060955, stock is #4060980). New coolant, and some vasoline.

1. Drain the coolant out of the bottom of the radiator (about 1/2 the coolant comes out)
2. remove the accessory belt
3. remove the water pump pulley
4. Loosen the 4 bolts holding in the water pump
5. Pull the stock pump out (here comes the other half of the coolant )
6. lube up the O-ring on the new pump with a little vasoline
7. push the new pump in
8. tighten it down evenly with your fancy 6 mm allen wrench
9. refill the coolant
10. replace the belt

Then follow the directions on how to wire up the relay. I needed one more loop end connector than was in the kit for the ground wires. Above I explained what wire I used for a switched 12 V source.

Then turn the key and make sure the pump is humming. Start the motor and watch the temp gauge. Make sure that it reaches operating temp and stays there (doesn't start to overheat).

Afterwards just make it a regular habit to check the temp gauge as you drive.
 
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