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Old 03-28-2012, 02:16 PM   #1
softballnrd27
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For those that have used the 87 Spectra tank/sending unit

I have everything installed and now I need to wire it up. I have the 87 fuel tank and sending unit with the EP381 fuel pump. I would like to get my fuel gauge working again so I need to know how to hook it all up. If you have a wiring diagram I would appreciate it.
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Old 03-29-2012, 02:24 PM   #2
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Re: For those that have used the 87 Spectra tank/sending unit

IIRC, the pink wire goes to the gauge, the other (tan?) wire is power. The pump will be grounded at teh tank, through the sender.
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Old 03-29-2012, 08:12 PM   #3
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Re: For those that have used the 87 Spectra tank/sending unit

iirc, gray to fuel pump power, purple to gauge, ground to ground.
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Old 03-30-2012, 10:42 AM   #4
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Re: For those that have used the 87 Spectra tank/sending unit

It is exactly the reverse of whet you would think; the lighter color is the gauge. The dual tank senders are differenct colors on each side, too.
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Old 05-08-2012, 12:32 PM   #5
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Re: For those that have used the 87 Spectra tank/sending unit

I am bringing this up again bc I am about to wire up my fuel pump and there are 2 different ways that came up.
Is it dark to power or light to power?
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Old 05-08-2012, 12:39 PM   #6
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Re: For those that have used the 87 Spectra tank/sending unit

I remember it is opposite of what you would expect. The A/M harness I used has a grey wire out to fuel pump power.
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Old 05-08-2012, 10:32 PM   #7
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Re: For those that have used the 87 Spectra tank/sending unit

Just to make sure that we are talking about the same thing, I have the spectre sending unit that has 3 wires coming out, 1 single wire for the ground and a 2 wire plug. I need to know which wire I supply the power from the relay to. I might have read your post wrong but it sounds like you are talking about the stock truck wiring.
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Old 05-11-2012, 01:35 PM   #8
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Re: For those that have used the 87 Spectra tank/sending unit

grey is power. purple is gauge.

hook up the purple. plug and unplug it and watch your gauge to confirm it is gauge.
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Old 05-11-2012, 02:07 PM   #9
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Re: For those that have used the 87 Spectra tank/sending unit

Quote:
Originally Posted by OldCreek View Post
grey is power. purple is gauge.
X2 this is correct
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Old 05-11-2012, 10:17 PM   #10
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Re: For those that have used the 87 Spectra tank/sending unit

Ok thanks guys. One more thing I plan to check off my list this weekend
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