5.7 Switched 12v

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Galvez83

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This question might seem crazy to some but i admit i am not a electrical guy. I ditched the carb after much suffering and installed a Holley Sniper 2. The wiring diagram requieres a "switched 12v red and a pink" to be run to the key. That is unreasonable on a 30ft boat. The question is, what wires can i use on the boat harness to feed these 2 wires. Is the purple that came from the coil an option or the carb choke wire? Engine model is VP 5.7gs PEFS.

Note....the Sniper 2 stays.

https://www.dropbox.com/scl/fi/anai...ey=hs42mqv1zxa6vz6762wegjd6z&st=ilrj64i0&dl=0
 
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Scott Danforth

Scott Danforth

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the purple wire is a switched 12 volt. that is the ignition.

you may want to understand the ABYC wire colors

Generic Boat Wiring information - Updated Verified

in an attempt to restore information lost due to broken links and photobucket. Here is a thread that will attempt to gather all pertinent generic wiring information starting with the SAE wiring colors as published by the ABYC American Boat and Yacht Council Standards COLOR ITEM...
forums.iboats.com forums.iboats.com

good luck with your sniper.
 
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Galvez83

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Thank Scott,

Would it be ok to tie both wires to the purple? Or just one and hunt for a secondary ignition wire?
 
alldodge

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kd4pbs

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You may want to run the existing switched supply to a relay which is wired to a circuit capable of lots of amps. These ECMs can draw more current than your original ignition circuit is capable of supplying.
One word of advice switching from carb to a throttle body EFI: Do something about the exhaust crossover passage in the intake manifold. It is very helpful for carburetor performance and very detrimental to TB EFI performance. Some guys will JB-Weld the thing closed.
 
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Donald0039

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Did you figure something that stops the electric fuel pump if the engine stalls?
 
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Galvez83

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Donald0039 said:
Did you figure something that stops the electric fuel pump if the engine stalls?
Click to expand...
Good question, the engine stalled several times due to low voltage from the battery. I had connected the sniper to the secondary battery while i had the switch on the primary. Every time that the engine stalled (due to low voltage from secondary battery) the pump shut off with the engine. Not saying its a clear sign but the 3 times it did turn off, so did the pump and all related equiptment in the sniper. Took a minute to figuere out what had happened on a brand new Sniper but eventually i found the issue out.
 
Scott Danforth

Scott Danforth

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ABYC and the Col Regs have requirements for either an oil pressure switch or powering the fuel pump from the alternator output.

What does the sniper have
 
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Galvez83

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Here is the breakdown,

1. Key-On Prime

With the key turned ON but engine not cranking, the Sniper ECU closes its internal “prime” circuit for about 2 seconds.

This drives the fuel-pump relay just long enough to pressurize the rail.

2. RPM-Dependent Run

Once you crank and the ECU sees a valid tach (RPM) signal, it re-energizes that same pump-relay circuit.

As long as the engine is spinning, the relay stays closed and the pump runs.

3. Safety Shut-off

If RPM drops out (stall or crash), the ECU immediately de-energizes the relay coil.

No relay coil → relay opens → pump stops
 
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Galvez83

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If anyone can advise what the correct idle rpms should be? Right now i have set at 800 when fully warm, i have a feeling its not right, as in too high. Not liking the loud clunk when going into gear. Any input?
 
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