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Discussion Starter · #1 ·
Hey guys, Im contemplating wiring up some thicker gauge power wire activated by relay to power my Walbro 255 in tank pump. Im confused on the possible locations to crimp the actual power though.

I was under the impression that the yellow/black wire above the cover was the power wire, but there is also a yellow/white wire. And once you take the cover off there is another connector plugged into the top of the tank with a yellow/white and a black.



When Im doing the direct wiring, would it be best to go all out and cut open the harness below the cover, drill a hole in the cover and run my new 12 gauge power wire and ground and connect as close down the wire as I can reach/solder without actually dropping the tank...

Or is it just the same to cut the power and ground wires above the cover at the harness connector there...?

What is the yellow/white and seperate ground for?

Just trying to see how you guys have done this before I have a go at it
 

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Discussion Starter · #5 ·
Stock wires do work, Ive never done this upgraded wiring either, but Ive seen information showing it allows the pump to flow more, and stabilizes it under electrical loads. I hate sitting at a stop light with my signal on and you can hear the pump tone changing with every blink. And when I up the boost to 25psi very shortly, Id love some peace of mind

I did read xenos install aswell JDMcrx91, but Im more concerned with if I am allowed, or if it would even be beneficial, to connect to the wires above or below that cover. If it was worth the trouble to go below.

Found out that the yellow/white was the fuel pump sendor signal, dont know how I didnt think of that
 

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Discussion Starter · #9 ·
Even the one you have pictured isnt oem size. The ONLY one that is exactly the same dimension is the Airtex FS121. I did re-use my stock one, but I think the pump itself is failing, as my car has been running lean, and the pump getting louder.

So I'll try this re-wire once I get outta my room finally, just to see what happens
 

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Funny how everyone eventually wants to run the 255 off of the (proper) bigger-sized wire.

Then everyone jumps in to say how they have been running their pump on OEM wiring without any problems for a while.

Then it kinda just slips out that the OP wants to wire his 255 with bigger wire because he suspects his pump is failing and maybe he's sorta possibly wondering if possibly somehow running the pump on the INCORRECTLY-SIZED OEM wiring for all this time has slowly burned out his pump.

-wire directly to the pump itself. I used 10awg.
-wire directly to the battery. I fused @10amp.
-do not touch the fuel-level sending unit wiring. (yel/wht)
-use the OEM wire (yel/blk) for the TRIGGER on a 30amp relay.
-you will need to drop the tank to get your NEW thicker wire all the way to the pump.
-also ground the pump to the chassis, AND give it a -ve return to the battery.
-consider hacking a few (hidden) killswitches into the OEM power wire (relay trigger).

Go look at my build thread, I just did all of this last week.
 

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Discussion Starter · #11 ·
Well my pump was used on my last setup and sat for years before using it this time. I just dont remember it being this loud, nor changing tones when I hit the turn signals.

I am not going to drop the tank today to wire it right to the pump, I will instead cut it as close as I can get reaching through the access hole under the seat and cut the appropriate ylw/blk and black wires for the pump and connect my 12 gauge from there. Then if I do end up swapping in a new pump and sock I can finish wiring it all the way when I drop the tank then.

If my tank was empty Id probably just drop it today, but Im 4/5ths full

I did look at your thread corksil, couldnt find any pics of how you went through the access hole in the floor
 

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you didn't find any of my 'access hole' pics because I dropped the tank.

What you did works I suppose. but it's... uh... well, nevermind! Good job!

Think of it all like a SYSTEM. Go ahead and rewire everything with the proper gauge wire, but that little 2ft section you left between the access hole and the pump actually negates the entire purpose of what you did.

I don't really know what else to say. Good luck with your turn signal problems.
 

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Discussion Starter · #14 ·
My question was simply how you got the power/ground through the access hole

The 2 feet of oem wire doesnt "negate" anything I did. Its still giving the fuel pump a DIRECT source straight from the battery, which is an improvement as to what was there. No oem relays or 20 gauge 23 year old wiring or long runs of wire.

I will eventually upgrade the last section the next time I drop the tank for whatever reason, but this is my daily and it had a full tank of gas so this is what I did on a sunday so I could either go ahead or hold off on buying another fuel pump, to see if it fixed my leaning out under 15psi @ 6k+rpm (and it did) and to boot it made the pump sound smoother.

im pretty stoked actually. This car rips. And now Im not scared to rip it and take me eyes off the gauges
 

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You know sometimes depending on the store you can actually find new pins for connectors at Pepboys. I've been lucky with this before and have just removed the pins from the connector made my own harness and pushed the pins back into the connector for that factory look. You could do that for the 2ft section your talking about. fo a fuel pump I don't see the need for anything bigger than 12 gauge but as the rule of thumb goes the larger the wire the bigger the load it can carry. I also would use less than a 20amp fuse. A small fuse sort of defeats the purpose of heavy wire.

I love doing wiring...NOT!!! Budweiser is also a required element of any good wiring job...lol
 

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My question was simply how you got the power/ground through the access hole

The 2 feet of oem wire doesnt "negate" anything I did. Its still giving the fuel pump a DIRECT source straight from the battery, which is an improvement as to what was there. No oem relays or 20 gauge 23 year old wiring or long runs of wire.

I will eventually upgrade the last section the next time I drop the tank for whatever reason, but this is my daily and it had a full tank of gas so this is what I did on a sunday so I could either go ahead or hold off on buying another fuel pump, to see if it fixed my leaning out under 15psi @ 6k+rpm (and it did) and to boot it made the pump sound smoother.

im pretty stoked actually. This car rips. And now Im not scared to rip it and take me eyes off the gauges
I sincerely apologize for bumping an old thread. I am new to the crx community.
My question was simply how you got the power/ground through the access hole

The 2 feet of oem wire doesnt "negate" anything I did. Its still giving the fuel pump a DIRECT source straight from the battery, which is an improvement as to what was there. No oem relays or 20 gauge 23 year old wiring or long runs of wire.

I will eventually upgrade the last section the next time I drop the tank for whatever reason, but this is my daily and it had a full tank of gas so this is what I did on a sunday so I could either go ahead or hold off on buying another fuel pump, to see if it fixed my leaning out under 15psi @ 6k+rpm (and it did) and to boot it made the pump sound smoother.

im pretty stoked actually. This car rips. And now Im not scared to rip it and take me eyes off the gauges
I sincerely apologize for bumping an old thread. I am new to the crx community. Idk how to private message. If you don't mind me asking i have so e questions regarding the way you installed the relay.
 

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The simple way is to use a 4 prong relay.
The coil side of the relay is wired to the oem plug connector that plugs to the fuel pump. That way it powers with ign switch.
If you don't want it powered by the ign. switch then it needs to be powered from battery + to a toggle switch and a wire for ground to chassis. Don't forget to use a fuse inline. And a toggle switch rated for the correct amp rating(walbro instructions should say) +- 20 or 30A.

The gate side of the relay also goes to
B+ ---> fuse holder---> +side of fuel pump.
Then the neg wire goes from fuel pump neg to chassis. as close to chassis from fuel pump as possible.
Depending on the Amps rate of the fuel pump you will need to make sure the wire powering the pump is rated to handle that many amps. Usually around 8ga, thicker is better to reduce resistance(what causes wires to melt).

Check you tube for vids, I might have missed a thing or 2.
 
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