454 long block options

While dressing my new long block Generation 6 L29's. I have come to some electric fuel pump wiring questions. Some will find this easy to answer.
As you may or may not know, The Generation 6 454's do not have provision for mechanical fuel pump. So I am forced to safely wire in an electric carter pump as an alternative to the mechanical pump my boat was built with.
I read about applying power to the pump in two ways.
1) While starter is powered up and engine rotating power is applied to the carter pump during starter engagement. How is this done specifically? My key switch appears to complete the circuit to a starter solenoid on the front of the engine. Where would I connect the pump for power here at? Wire colors are yellow and red stripe.
2) I know the importance of an operating engine with fuel pump powered up. Knowing this; I have installed a two wire normally open oil pressure switch p/n PS126 (standard) which will complete a circuit with positive oil pressure above 5 PSI or so. How would I wire this switch? Ground or positive to complete circuit keeping in mind requirement for running pump with starter powered up from key switch.
Thinking out loud... 5 PSI is almost immediate so do I even need to complete the circuit with starter engagement? My thoughts are so long as engine is in rotation; pump should be running. Help me to understand the right way to wire an electric fuel pump using a two wire normally open pressure switch which completes a circuit above 5 PSI.? Thanks
 
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The mechanical pump on my L29 is attached to the raw water pump. It's belt driven.
You need 12v to an electric fuel pump. I think I would have the 12v coil wire engage a simple relay if I were modifying my boat for an electric pump. Otherwise, I'd run a wire up to the dash and have a dedicated switch possibly.
 
Good call on the Oil Pressure switch. Wire it through the Ground but it needs to close a relay and not operate the fuel pump directly. Most OP switches cannot take the current needed to operate a motor; check the switch rating. The keyswitch start position should bypass the relay during cranking and bridge until oil pressure comes up. The keyswitch Ign position should power the relay.
 
First ALL the electrical parts, pump, oil switch, relays, must be "Ignition Protected" or say "SAE-J1171"

Then yes the oil switch is a must, it prevents the pump from continuing to run should the engine die for any reason, thereby preventing any possibility of over flow, leaks under pressure. This is fire safety. The oil switch should get power from the coil "ignition switch" side. So it is hot only with key "on". May need to check wire size and fuse sizes. If to small add a relay and fuse for the pump and have the switch and ignition control the relay.

Next the pump must be mounted within 12" of the engine. This is why you see cool fuel and EFI/MPI pumps mounted near or on the engine. Again minimizing any fuel lines that are under pressure. Best is to mount on a plate on the engine, isolate the plate and/or pump from heat with a suitable rubber mountings (reduce chances of vapor lock pump). But the casing may also need to be grounded if a single wire pump so a flexible ground wire. Use a hard steel line from the pump to the carburetor, no hoses.

If you must mount the pump to the stringers use pressure rated fuel line and good fittings on the outlet side. Keep any hose as short as possible. But long enough to allow for vibration, engine flexing.

Now the circuit.
With only the oil switch you will not refill the carbs until you crank up oil pressure. This could lead to extended cranking after sitting for days, or after a hot run heat soak of the carbs may boil off the fuel in the bowls. If the engines get oil pressure quickly this may not be an issue.

If you find they don't get oil pressure fast enough you need to get a bit more complicated, to pulse the relay while cranking. That is not as simple as connecting to the starter, you need a blocking diode else the fuel pump circuit would try to back feed and crank the engine.
 
With only the oil switch you will not refill the carbs until you crank up oil pressure. This could lead to extended cranking after sitting for days, or after a hot run heat soak of the carbs may boil off the fuel in the bowls. If the engines get oil pressure quickly this may not be an issue.

If you find they don't get oil pressure fast enough you need to get a bit more complicated, to pulse the relay while cranking. That is not as simple as connecting to the starter, you need a blocking diode else the fuel pump circuit would try to back feed and crank the engine.

This is what I was thinking. So for now I think I'll just wire it trough the pressure switch. According to Federal Mogul, my pressure switch is rated for 5amps continuous and closes at 6 PSI. The carter pump is drawing 1.2 amps with float closed and with engine running fluctuation around .6 - .7 amps.
I always planned to plumb lines with inverted double flared fittings and pictures will show the same.
For now leaving it as is. Purple wire to one post of pressure switch. Second terminal headed toward pump hot line. Grounded pump. I believe this will work just fine. Plus no issues with starter slinging oil through system before bowl fills up. Thanks for the very useful information. BTW I love your video loading your boat in NC.
 

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Now the circuit.
With only the oil switch you will not refill the carbs until you crank up oil pressure. This could lead to extended cranking after sitting for days, or after a hot run heat soak of the carbs may boil off the fuel in the bowls. If the engines get oil pressure quickly this may not be an issue.

If you find they don't get oil pressure fast enough you need to get a bit more complicated, to pulse the relay while cranking. That is not as simple as connecting to the starter, you need a blocking diode else the fuel pump circuit would try to back feed and crank the engine.
I'm a little worried about the violet colored wire current draw from the ignition switch.
With electric choke, New carter fuel pump, and New Delco EST distributor I would think I'm getting close to the 5 amp breaker limit.
What is the typical amperage draw for electric choke (Rochester Quadrajet)?.
Also what is the current draw on the Delco EST voyager ignition system?
 
Double check the "ignition breaker" size.
I show 10 amp as standard by Sea Ray, and the Mercury diagrams show 20 amp fuse.
My 350s have a 10 amp ignition breaker, wire size is good at 16 AWG,

basic wiring confirms this is the standard way to hook up DST and a fuel pump
Also notice it has the starter solenoid wiring hookup
(IF you have a four terminal solenoid, the "R" was to bypass the coil ballast "Resistor" for hotter spark while cranking)
https://bpi.ebasicpower.com/downloads/EDMbasewiring.pdf
 
Double check the "ignition breaker" size.
I show 10 amp as standard by Sea Ray, and the Mercury diagrams show 20 amp fuse.
My 350s have a 10 amp ignition breaker, wire size is good at 16 AWG,

basic wiring confirms this is the standard way to hook up DST and a fuel pump
Also notice it has the starter solenoid wiring hookup
(IF you have a four terminal solenoid, the "R" was to bypass the coil ballast "Resistor" for hotter spark while cranking)
https://bpi.ebasicpower.com/downloads/EDMbasewiring.pdf
thank you! so sounds like I should be able to run all three devices off the violet wire?
coil, choke and fuel pump.
I do have have a 4 terminal start solenoid. What color wire is connected to the "R" terminal? I'll take a picture of my install later this week.
I will say; At present; it doesn't appear like I need to shoot power during starter engagement to the newly installed electric fuel pumps just yet as the bowls seem like they're holding fuel nicely.
I went out this morning and with throttles at idle both started ridiculously and effortlessly. (1/2 second to running) Plus they continued to stay running which suggests they're being refilled quickly due to new engines and the 6 PSI pressure switches I installed. Thanks again for you expertise. Your responses are valued sir!
Edit: Included additional information and correction of some typos.
 
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Your location lends to Dawsonville/Melling... But, https://www.michiganmotorz.com/marine-engines-c-31.html seems to have the best and most reviews around here on CSR
And so Infact I did use Michigan Mortz. They were helpful. I chose new long blocks. It didn't come without surprises though.
Electric fuel pumps required
Electric choke carbs
New Style flywheel (Externally balanced)
New Delco EST distributors required due to hydraulic roller camshaft
$16K for both shipped to my local terminal.
Machine shop had stripped intake manifold of paint and muck.
Additionally had to remove from the bottom of the intake manifold, the Mark IV carburetor crossover heat shield to clear the roller lifter alignment plate in galley. Easy enough but follow up cleaning and painting delayed things.
All in all happy I chose the new engines over rebuilt hackers.
 
Now 55 hours on the new 454's. Port engine limited to 4400RPM for some reason and the Stbd. engine will spool to rated max of 4600.
Sure is nice. No oil leaks, easy cold starts and they just run and run. New is best. Now that engines run great spending time and money upgrading the appearance both inside and out.
New engines rock
 
Now 55 hours on the new 454's. Port engine limited to 4400RPM for some reason and the Stbd. engine will spool to rated max of 4600.
Sure is nice. No oil leaks, easy cold starts and they just run and run. New is best. Now that engines run great spending time and money upgrading the appearance both inside and out.
New engines rock

I would recommend you spend a couple bucks finding the root cause of the low rpms. It's very concerning and should be addressed ASAP so not to cause any warranty issues with an engine that is assessed to have not been running correctly.
 
I would recommend you spend a couple bucks finding the root cause of the low rpms. It's very concerning and should be addressed ASAP so not to cause any warranty issues with an engine that is assessed to have not been running correctly.
I swapped tachometers and problem too swapped. Looking at new gauge options for my classic 350. Thanks
 
I swapped tachometers and problem too swapped. Looking at new gauge options for my classic 350. Thanks

You may want to try vigorously rotating the 4-6-8 switches back and forth on the back of the tach's to clean up the connections as these are a known problem causing tach issues.
 
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