Under-hood switched 12V source?

[Dingleweed]

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]

don't you have a test light or volt meter to find one?

 

[Dingleweed]

I had one, but couldn't find it today. I'll probably go buy another one tomorrow...

 

[Dorsai]

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]

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

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]

Good job, I probably should have asked if you had a complete relay kit....

 

[Miles]

Why did you decide to get an electric water pump? How much hp do you gain?

 

[Dingleweed]

Why did you decide to get an electric water pump? How much hp do you gain?

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]

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

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

 

[Dingleweed]

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

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.