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AutoMods
05-02-2011, 02:12 PM
For my dual walbro setup, I want to just use my factory positive 12v, 14 gauge wire that powers my old single walbro setup. Reusing this wire allows me to not have to worry about drilling through the fuel pump lid and sealing the hole for a new larger gauge wire.

A couple inches after the wire comes out the top of the lid I can up it to 10 gauge just to be extra safe. My question is if you run a few inches of 14 gauge wire and than convert it over to a larger gauge, can I technically use the 3 foot column in the wire gauge selection chart?

wire gauge selection chart
http://www.rbeelectronics.com/wtable.htm

The cut wire on top is the 12v wire
http://www.importevolution.com/temp/pump_sending_unit.jpg

http://importevolution.com/articles/hp255lph.jpg

sparkles
05-02-2011, 03:44 PM
You probably could, but I'll put it to you like this. Even if you're soldering everything, every time you cut and make a wire connection to another wire, you're creating a disruption in the flow of electrons in the wire creating a hot spot and a possible fail point. Why not just bite the bullet and run a solid piece of 10ga. all the way through? If you do leave a small section of 12ga, it'll probably work, but it's going to get hotter than the rest of the wire. The last place I would want that to occur is around my gas tank.

slow ride
05-02-2011, 04:34 PM
Ryan, I would run the larger stuff all the way to the pumps and get rid of that tiny 6mm outlet and go with a larger bulkhead. You could use the old pressure line for return if you want I'd think and cap the old return. Do it right once as it will make more power down the road I'm sure.

clutchmuch
05-02-2011, 11:44 PM
http://www.importevolution.com/temp/pump_sending_unit.jpg


I'm agreeing with the two. Especially sparkles about the hot spot.
But i just had to say. I don't enjoy this picture. My fuel pump was a complete asshole.

sparkles
05-03-2011, 08:00 AM
I'm just saying, being an electrician and having had my hands in about every single thing you could thing of, from rewiring houses, to 24v DC Metro Buses, to 800hp DC motors at tire manufacturing facilities, to 480v 3/0 control wiring. You name it. I've seen some funny things. I've seen a lot of "rigged up" things as well and they usually never wind up lasting long. Harmonics is something nobody ever seems to think about either, but not really an issue with 12v DC wiring. I'm just saying, it'd make me poop a little if I found out after a while that the wiring in my bulkhead above a tank of gasoline has obviously been a little hot judging by the crispiness of the wire sheath.

AutoMods
05-06-2011, 07:55 PM
anyone know if those electrical plastic bubbles are removable? they will spin with force but the lower half on the other side of the lid also spins. i'd try more but they seem brittle and don't want to break them if they aren't removable.

sparkles
05-22-2011, 09:01 PM
What did you find out about the rubber wire seal things? I'm going to start on my pump rewire this week. Did you wind up doing the bulkhead thing or use the stock lines?

AutoMods
05-22-2011, 09:23 PM
i used a rubber grommet and ran a new 10 gauge wire. i used a 3/8 npt kobalt lowes air compressor fitting. this isn't mine but same silver fitting http://richmondperformancemusclecars.com/photos/mm/images/26310/original.aspx

sparkles
05-23-2011, 06:36 AM
Are you running the second pump off of another relay, or are you running them both off one 10ga wire in parallel?

AutoMods
05-23-2011, 10:42 AM
i've actually been out of state for the last 10 days so its not done yet but the plan was to Y the two pump power wires together by soldering them under the tank lid so they would share the power 10 gauge power wire. also share the 30 amp relay and 30 amp fuse