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hatched91
09-11-2006, 10:38 PM
okay, here's the story. i bought a used fuel sending unit. the fuel sending unit that i purchased used, was not disconnected from the fuel pump, the wires were cut. i decided to go ahead and cut my wires and splice the negative to the negative and positive to the positive. i used butt-connectors with plastic covering. now, after doing it i'm afraid to put it back together. i do not want the rubber to spark or the two wires to touch, what should i do?
http://img105.imageshack.us/img105/6756/0000467gn6.jpg (http://imageshack.us)
http://img291.imageshack.us/img291/2453/0000468nh2.jpg (http://imageshack.us)
http://img175.imageshack.us/img175/3277/0000469vc2.jpg (http://imageshack.us)

Alexlind123
09-11-2006, 10:45 PM
lots of electrical tape?

BillionPa
09-11-2006, 10:49 PM
electrical tape + gasoline = bad.

if you are using gas without ethanol in it you shouldnt have any problems, but ethanol makes it conductive so i dunno there.

i would fill the little plastic thing with some kind of permatex silicone sealant thats solvent resistant.

Alexlind123
09-11-2006, 10:52 PM
Heat-shrink tubing.

Rus
09-11-2006, 11:28 PM
Solder the wires and use heatshrink tubing. That would be the most secure way of making the connections.

hatched91
09-11-2006, 11:49 PM
i have heatshrink ready to be slid over the butt connectors. will the gas just eat up the heatshrink?

Kobe Diesel
09-12-2006, 01:09 AM
wire insulation and heat shrink are available for use in oil/gas applications.

genphreak
09-12-2006, 02:02 AM
i have heatshrink ready to be slid over the butt connectors. will the gas just eat up the heatshrink?Strip, solder and shrink. Don't bodge it, this is not a place you want to mess. Even if you get a dodgey gauge (or just the perception of one) you'll always be blaming corrosion in your connector. Do it properly and be done with it is my advice. Nuff said.

hatched91
09-12-2006, 10:45 AM
where would i obtian some gas proof heat shrink? i have some already as you can see in the picture that is pulled up above the connection, but i do not believe it is gas-resistance or gas proof.

Dr. evil
09-12-2006, 10:55 AM
Butt splices are the only type of connector approved for aviation (witch are as strong or stronger that the wire). solder has a tendency to brake, if it was me i would call it good at that.

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Bill R.
09-12-2006, 11:17 AM
did you stagger the cuts so that the new connectors aren't side by side where a bare wire could contact each other. But in your case since its done i would just use the shrink tubing that you have already on there, slide it over it, shrink it and assemble it. You won't find any silicone sealer that is suitable for long term immersion in gasoline. Regardless of what the aviation industry may do, i prefer solder joints in automotive use, less chance of a poor connection, speaking of solder joints ,here's a fun little job that i got to do last week splicing in half the wiring harness and fuse box on a gmc truck that somebody decided to substitute a solid copper wires for the fuse on the a/c blower motor circuit.. and it melted half the harness and started a fire under the dash when the relay shorted to ground.





okay, here's the story. i bought a used fuel sending unit. the fuel sending unit that i purchased used, was not disconnected from the fuel pump, the wires were cut. i decided to go ahead and cut my wires and splice the negative to the negative and positive to the positive. i used butt-connectors with plastic covering. now, after doing it i'm afraid to put it back together. i do not want the rubber to spark or the two wires to touch, what should i do?

hatched91
09-12-2006, 07:05 PM
wow, looks like fun. no, not only did i cut the wires, i did not stagger them either. i would just try to zip tie them against each fuel line, but then again i could be risking my car and even my life. i already ordered a new sending unit, i needed a new one to begin with, but this used one was $10 from a guy parting out a 525. oh well, $10 lost, lesson well learned. now i get to go 3 days without a car. fun fun! putting in the new one will be a piece of cake!

ricola
09-12-2006, 07:36 PM
As long as you use shrink tube on the wires I would worry about. Personally I would solder, then double shrink tube without the crimp splices. The shrink tube when heated get sticky inside and fuses itself to the wire when cooled. If the wire slides out of the crimp splice.... BOOOOOOM!

All Automotive electical repairs should be soldered. Your goal is to make a connection that won't fall apart, then insulate the connection. If your worried about your shrink tubing, shrink some onto a section of wire and hang it into your lawn mower tank over night. I think you'll find it's fuel safe.

hatched91
09-16-2006, 02:34 AM
i went ahead and just ordered a brand new one to be safe. i did find gas-proof heat shrink at a local motor shop. the gear heads there probably blew up a few cars figuring that stuff out.