A word about re-wiring your fuel pump. [pics]
 

So last night I park my car on the street and today I try to start it and it won't turn over. I check the fuel pressure gauge, and it's sitting at zero. Great.

After checking the wiring between the battery & the fuel tank bulkhead in the trunk, I couldn't find a problem. So I decide to pull the bulkhead/assembly from the tank.

Well, awhile back I rewired my fuel pump with 10gauge wire and a new relay...however I did not re-wire the part inside the fuel tank - bad idea.

Check out the sweet 16 gauge wire connecting the fuel pump to the top of the bulkhead. Oh yeah, and check out the sweet melted connector.

https://www.rx7club.com/attachment.p...1&d=1284326491

https://www.rx7club.com/attachment.p...1&d=1284326491

Well I just walked to Lowes in the rain and got some rubber grommet pass-thru, a drill, a drill bit, wires, connectors, and crimps. Oh yes, working on the side of the street, in the rain is SOOOOO fun.

Let this be a lesson to everyone who has, or is considering, rewiring the fuel pump. :blush:

Your sock filter looks dirty and it may ruin your pump if it's clogged up.

yeah good call. The factory wire can overheat. Here's my rewire--8 gauge (yeah that's overkill) right into the tank for a Supra pump.

https://www.rx7club.com/attachment.p...1&d=1203786449

the bulkhead connector is the main failure point. redo the bulkhead on top of the tank with pass through wires, just be sure they are sealed up well, you don't want fuel leaking out near your exhaust...

"....overkill" is an understatement. #12 (or even #14) is all that's required (for a single supra pump). #10 would be overkill. Anyone replacing in tank wires should be sure the insulation is compatible with fuel; e.g., gasoline and/or alcohols, to avoid potential and future safety issues.

yes I used some rubber grommet pass-thrus to run 10gauge through the top of the bulkhead. sealed up nice and tight!

back in business.

yes i noticed that also but i need to order one.

anyone know the best place to order one?

true that too, i was cringing when i saw the speaker wire just thinking what would happen if the insulation swells up and the wires rub together..

Be cautious.... A friend of mine did this, and the gromet was sealed up nicely.... after nearly causing a fire in his car, owing to gas near a relay, it turns out that fuel can actually travel up the *inside*of the cable (it leaches up the copper strands..... think of a kind of syphon effect) just keep an eye out is all I'm saying.

the proper way to do a bulkhead connector is to use a stud/insulator method.

the stock S4 FCs use a passthrough bulkhead style connector and have none of these issues, i just have never tried to see if the dimensions are all the same to work in a FD fuel tank.

Thanks for posting. This reinforces my position to leave this un-modded. :)

That is correct. I was thinking the same when I rewired my pump.

Yea, that makes sense...

it's been in there for years now with zero problems. That's actually relatively expensive amp wire. It's hardly a pretty install, but the concern about fires and fuel eating up insulation is completely overblown. I don't even have a grommet (yeah I said it, NO GROMMET FOR YEARS), just a bit of RTV where the wire goes through the hole. I've also had zero fuel pressure problems or electrical problems with it and have run up to 21 pounds of boost.

Well if you stop posting suddenly we'll know why! Just kiddin :lol:

apparently this stuff is "gasoline safe"
http://www.neverseezproducts.com/gasketseal.htm

SOOOOOO....

Any idea where to get a new filter sock?!

So is there some special designation of wire people should be looking for to ensure that the wire is safe to use around fuel?

I believe tjhat advanced or auto zone sell replacement socks for the supra pump. You will have to look under the supra of course;)

http://shop.advanceautoparts.com/web...51_10051_-1___

The Denso part is at the bottom of the list.

Denso Fuel Pump Filter/Strainer
Part No. 952-0029
$21.99

Came to about $30 shipped from Advanced. I saw they have them on eBay for $5 less (shipped) but I wasn't sure if it was authentic Denso or not.

Thanks!

there's still few places where i would try testing to see what works and what doesn't. speaker wire is for speakers and wasn't designed to be mixed with petrol fuels, perhaps it does work but if it ever fails then you will have as close to an explosion of fuel as fuel can possibly make in the semi pressurized/enclosed fuel tank.

From what I've researched, most high-quality "automotive primary wire" is gasoline-safe. I ordered some 10-gauge to replace the temporary wiring I used to get my car home the other day - obviously it works for now, but I would rather have it done right vs. driving around with a ticking time bomb in my trunk.

Not a place to mess around unless the proper materials and closures are used. Make sure wire is rated:

http://database.ul.com/cgi-bin/XYV/t...388&sequence=1

http://www.panduit.com/groups/MPM-GA...ONT_034680.pdf

TEF and PTFE are also acceptable insulation for immersion in gasoline:
http://www.thermalwire.com/temp_appliance.htm

Grommets are not acceptable closures for a fuel tank; they would never pass tech at the track to say the least. There are quite a few bulkhead electrical connectors that are suitable. At the bare minimum use insulated post and stud with nylon, teflon, or polyethylene insulator / seals.

The addition of ethanol and octane boosters further complicates resistance to breakdown.

good thing I'm not using speaker wire

http://www.google.com/products/catal...d=0CC0Q8wIwAg#

"Phoenix Gold PF2W8R100 100' Spool 8-Gauge Power Wire - Ruby
Oxygen-free high conductivity copper - chemical and temperature resistant jacket"

https://www.rx7club.com/attachment.p...1&d=1284422817
another site listed it as 735 strands of 40 gauge wire. It's flexible and easy to route. I use the same style of wiring for my battery relocation. It's expensive wire, I just got a good deal on it because my friend had access to huge discounts at the time.

What about this:

http://www.summitracing.com/parts/SUM-G1431/

https://static.summitracing.com/glob.../sum-g1431.jpg

I think a thread consolidation is needed, there is too much good information directly related, but in different threads.