Blue wire???

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f26yrn04558-72
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Blue wire???

Post by f26yrn04558-72 »

I have a 72 f250 custom, no extras except a tach. My question is what this plain blue wire connects to. I have looked at as many wiring diagrams as I could find, even the junk yard. I think it may go to a aux fuel tank. I have attached a picture of this wire.
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390Nut
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re: Blue wire???

Post by 390Nut »

Only blue wire I see on the diagram here: http://www.fordification.com/images/sch ... _quick.jpg is for a "carb throttle switch" whatever that is :?
Paul
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`69 F100 390 4spd driver
http://www.fordification.com/galleries/ ... ?cat=10251
Dura-Spark II Conversion info at:
http://home.comcast.net/~390nut/Dura-SparkII.htm

Pipes71 did once say, "bumps and bikes.. what a great combo!" :thup:
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390Nut
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re: Blue wire???

Post by 390Nut »

More info. Looks like Blue wire is for the throttle solenoid, according to this diagram: http://www.fordification.com/images/sch ... master.jpg the blue wire is #932 in the diagram, and it looks like it's part of the A/C system possibly. (right below the starter in the schematic)
Last edited by 390Nut on Tue Jun 13, 2006 7:42 pm, edited 1 time in total.
Paul
Image
`69 F100 390 4spd driver
http://www.fordification.com/galleries/ ... ?cat=10251
Dura-Spark II Conversion info at:
http://home.comcast.net/~390nut/Dura-SparkII.htm

Pipes71 did once say, "bumps and bikes.. what a great combo!" :thup:
f26yrn04558-72
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re: Blue wire???

Post by f26yrn04558-72 »

I see the one for the carb throttle switch, the carb does not have a switch or sensor on it that I'm aware of. If any one has a picture of this setup please post it. p.s did the picture come through?
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390Nut
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re: Blue wire???

Post by 390Nut »

Yep, it came through. Probably got removed with the carb at some point, hence the wire getting cut. I wouldn't worry about it, but I WOULD cap it off, as it looks to have power from the ignition switch in the run position.
Paul
Image
`69 F100 390 4spd driver
http://www.fordification.com/galleries/ ... ?cat=10251
Dura-Spark II Conversion info at:
http://home.comcast.net/~390nut/Dura-SparkII.htm

Pipes71 did once say, "bumps and bikes.. what a great combo!" :thup:
f26yrn04558-72
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re: Blue wire???

Post by f26yrn04558-72 »

I planed on capping it. thanks for the reply. Just curious what does it do?
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390Nut
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re: Blue wire???

Post by 390Nut »

The throttle solenoid on the carb serves a couple functions. In the simplest form (spring powered) it keeps the throttle from "chopping" when you let off the pedal. That is, the throttle springs shut to a certain point, then slowly closes the last 1/8 to 1/4 inch or so. Emissions junk, really, but it helps to keep the fuel flow consistant with the movement of the truck, as it comes to a stop. Not truly necessary, unless your emissions testing is tough enough to warrant having it there.

I THINK that the electric ones, such as what your truck evidently had, is also used to control the idle on an A/C equipped vehicle, so that the idle doesn't drop when the A/C is turned on. There may be other intentions, or reasons for the electric power to the switch (perhaps the spring tension alone wasn't durable enough over time? dunno for sure)
Paul
Image
`69 F100 390 4spd driver
http://www.fordification.com/galleries/ ... ?cat=10251
Dura-Spark II Conversion info at:
http://home.comcast.net/~390nut/Dura-SparkII.htm

Pipes71 did once say, "bumps and bikes.. what a great combo!" :thup:
f26yrn04558-72
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re: Blue wire???

Post by f26yrn04558-72 »

That makes sense. thanks for the info!!!! the truck runs perfect, except until it worms up for a minute or two.
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re: Blue wire???

Post by 68F250 »

If you ever convert to electronic ignition, that's the perfect place to get the +12 volts to power the unit. It is hot in the start and run positions.
Barry

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f26yrn04558-72
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Post by f26yrn04558-72 »

Yes it is, I was thinking about converting it over, not shure though. I was thinking og keeping it all stock. Any recomandations on what type of unit/brand to install? How much do they $$$$
72 F250 Camper Special
72 F250 Factory Highboy Custom
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