460 Electrical Fuel Pumps Starter Relay

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460 Electrical Fuel Pumps Starter Relay

kramttocs
Administrator
If I understand correctly the 4 post starter relay has two posts that are hot in start - the small one for the fuel pumps and the big one for the starter (let's assume a factory starter).

Why are there 2? Why isn't the fuel pump one just connected to the starter one?

I know I am missing something here.
Scott
'Camano' 1986 F250 Supercab XLT Lariat 460/C6
'Chanute' 1980 F350 C&C 400/NP 435 - Gin Pole

But there ain't nothin' wrong with the radio
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Re: 460 Electrical Fuel Pumps Starter Relay

Gary Lewis
Administrator
You have it correct.  However, the reason for two connections is that the one to the fuel pump relay is a push-on like the one to pull the starter relay in, the little red/light blue one.
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: 460 Electrical Fuel Pumps Starter Relay

kramttocs
Administrator
Thanks! That makes sense. Seems like ford could have just put a ring terminal on it though

If converting to a Bosch relay would you just get a 50amp relay, hook the r/lb to the relay trigger and then both the pmgr trigger wire and the fuel pump wire  to 87?

I know I said factory starter originally and am now throwing in the pmgr starter.
Scott
'Camano' 1986 F250 Supercab XLT Lariat 460/C6
'Chanute' 1980 F350 C&C 400/NP 435 - Gin Pole

But there ain't nothin' wrong with the radio
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Re: 460 Electrical Fuel Pumps Starter Relay

Gary Lewis
Administrator
Yes, I'd find a heavy duty Bosch relay, but make sure it has the right sized lugs.  I know that Jim and maybe Bill are running a stock Bosch relay, but I would like a heavy duty one if possible.  I like overkill.  
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: 460 Electrical Fuel Pumps Starter Relay

kramttocs
Administrator
I agree with overkill.
Was a little surprised though that the powermaster starter instructions showed a need for the trigger wire to handle 50amp intermittent (10 continuous).


The 50 throws a wrench in using the Eaton box if I ever wanted to ditch the fender mount.

I'd be curious in what amps the one Jim or Bill are using.
Scott
'Camano' 1986 F250 Supercab XLT Lariat 460/C6
'Chanute' 1980 F350 C&C 400/NP 435 - Gin Pole

But there ain't nothin' wrong with the radio
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Re: 460 Electrical Fuel Pumps Starter Relay

ArdWrknTrk
Administrator
I have published the test page graph of my DB Electrical starter motor back on FTE.
~40A to pull and 13A to hold.

I'm using the 40A relay that came in my cheap PDC box.
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.
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Re: 460 Electrical Fuel Pumps Starter Relay

kramttocs
Administrator
Thanks Jim. Didn't expect it to require that much for just the relay.
Scott
'Camano' 1986 F250 Supercab XLT Lariat 460/C6
'Chanute' 1980 F350 C&C 400/NP 435 - Gin Pole

But there ain't nothin' wrong with the radio
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Re: 460 Electrical Fuel Pumps Starter Relay

ArdWrknTrk
Administrator
I think even a regular 30A could handle it easily.
But the option was there for me.

Three weeks in, and it works every time. 👍
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.
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Re: 460 Electrical Fuel Pumps Starter Relay

kramttocs
Administrator
This post was updated on .
Since I was hooking some of this up yesterday I was going through my disassembly notes/photos.
This blue wire wasn't hooked up on the truck when I got it and this was confirmed by needing to dig out crud from the push connector that goes to the starter relay.
I only drove the truck in winter weather for a couple months before I took it down to the redo. It started great the majority of the time BUT if it didn't start fairly quickly it took quite a bit of cranking though.

I am still learning about the whole hot-fuel setup but would this plug being unhooked cause that because it's not filling the carb while in start? Or is this whole harness somewhat optional with mixed results?
Scott
'Camano' 1986 F250 Supercab XLT Lariat 460/C6
'Chanute' 1980 F350 C&C 400/NP 435 - Gin Pole

But there ain't nothin' wrong with the radio
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Re: 460 Electrical Fuel Pumps Starter Relay

Gary Lewis
Administrator
Sorry Scott, what blue wire?  
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: 460 Electrical Fuel Pumps Starter Relay

kramttocs
Administrator
THE blue one of course

Had actually thought I'd referred to it in more detail in the first post but looks like I didn't.

This is the blue one that connects to the starter relay. Fuse Link T. Looks like it turns into PK/BK after the fuse but that is under my aluminum plate so can't visually confirm.






*little side question - can a hyperlink be added to the top of the individual EVTM pages that allows one to go back to the EVTM topic page? The back button usually works but I often go to these pages from my search history. Not a big deal.
Scott
'Camano' 1986 F250 Supercab XLT Lariat 460/C6
'Chanute' 1980 F350 C&C 400/NP 435 - Gin Pole

But there ain't nothin' wrong with the radio
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Re: 460 Electrical Fuel Pumps Starter Relay

Gary Lewis
Administrator
I'm confused.  I assumed you have an ammeter and the schematic below would be the correct one.  And there is a blue fuse link, but it is Fuse Link S, not T.  And it is yellow not pk/bk.  So I'm lost.

And, that can't be disconnected as you shouldn't be able to get the truck started since it provides power to the fuel pump.  

As for a hyperlink, if you use the '85 EVTM there is one called Index at the top of each section.  Is that what you mean?





Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: 460 Electrical Fuel Pumps Starter Relay

kramttocs
Administrator
The 1985 EVTM links are even better than I was thinking of! I always go to the 86 so hadn't ever seen those.

---

We are almost on the same page

First, I am planning to hook everything back up like factory so just curious about the workings of it since it wasn't hooked up when I got it.

Yes, the battery side fuse link S that ultimately makes its way to the fuel pumps via the relay (triggered by oil pressure switch) was always connected.

It's the 'HOT IN START'  fuse link T that wasn't (second photo you posted). I believe this primes/fills the carb until the oil pressure is enough to trigger the switch and then fuse link S takes over.

So guessing that if you crank it long enough the pressure will build up (even before the engine is running) and cause the fuel pumps to kick in via fuse link S.



Scott
'Camano' 1986 F250 Supercab XLT Lariat 460/C6
'Chanute' 1980 F350 C&C 400/NP 435 - Gin Pole

But there ain't nothin' wrong with the radio
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Re: 460 Electrical Fuel Pumps Starter Relay

kramttocs
Administrator
Turns out the blurb on 106 of the 86 EVTM gives some detail on it.
Scott
'Camano' 1986 F250 Supercab XLT Lariat 460/C6
'Chanute' 1980 F350 C&C 400/NP 435 - Gin Pole

But there ain't nothin' wrong with the radio
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Re: 460 Electrical Fuel Pumps Starter Relay

Gary Lewis
Administrator
In reply to this post by kramttocs
Ahhh!  Dawn!   Marblehead!  Yes, we are now on the same page.  


Yes, Fuse Link T provides power to the pump while cranking.  But if you crank it long enough the oil pressure should come up and, if there is sufficient battery power left, the pump will fill the carb.

So, it should be hooked up, for sure.


Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: 460 Electrical Fuel Pumps Starter Relay

Gary Lewis
Administrator
In reply to this post by kramttocs
kramttocs wrote
Turns out the blurb on 106 of the 86 EVTM gives some detail on it.
Yep.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: 460 Electrical Fuel Pumps Starter Relay

kramttocs
Administrator
In reply to this post by Gary Lewis
Gary Lewis wrote
 if there is sufficient battery power left
Haha very good point.

Mystery solved
Scott
'Camano' 1986 F250 Supercab XLT Lariat 460/C6
'Chanute' 1980 F350 C&C 400/NP 435 - Gin Pole

But there ain't nothin' wrong with the radio
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Re: 460 Electrical Fuel Pumps Starter Relay

gotfords
In reply to this post by Gary Lewis
so i have now a 84 f250 460 dual tanks...where is fuel pump relay?
where is inertia switch?
thanks
TOMMY SIDES
KINGMAN AZ

1986 F150 SWB 2WD REG CAB INLINE 6
4BBL CARB OFFY INTAKE SPLIT HEADER LOWERED 3" F AND 4" R

1984 F250 LWB 2WD REG CAB 460 CARB CALIFORNIA TRUCK
IT PASSES SMOG...LOL

1980 f100 REG CAB SHORT BED 2WD...NO MOTOR OR TRANNY YET!!! FACTORY 300 W/MANUAL IN FLOOR AND A/C
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Re: 460 Electrical Fuel Pumps Starter Relay

kramttocs
Administrator
The fuel pump cut off relay is to the right of the brake booster when looking from the front of the truck. There is a square-ish plastic cap screwed to the firewall that the relay snaps into from underneath. Note that this can hold two relays so it's a good location to add another (or move the trailer relay to) and keep it looking clean.

The inertia switch is inside the cab on the passenger side of the hump. There is a square cutout in the firewall pad. Little square box with a white rectangular push button on it.
Scott
'Camano' 1986 F250 Supercab XLT Lariat 460/C6
'Chanute' 1980 F350 C&C 400/NP 435 - Gin Pole

But there ain't nothin' wrong with the radio
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Re: 460 Electrical Fuel Pumps Starter Relay

85lebaront2
Administrator
First I will address the blue wire, it is a "priming" wire and goes to the NC side of the fuel pump relay. It's purpose is to power the selected fuel pump when cranking to fill the float bowls. I used to cheat when Darth still had the carburetor, if he had been sitting for a while, I would open the hood, take the blue wire off it's terminal and touch it to the battery side of the starter relay, I would listen for the change in sound of the fuel flow indicating the float bowls were full.

Wiring, I am using the 1995 battery cable set Jim salvaged for me, it uses the standard Ford starter relay, but it only powers the starter solenoid on the factory PMGR starter (I refuse to pay an exorbitant price for a starter when Ford has a perfectly good one). I have been using this setup since my son sourced me a late model PMGR starter probably 20 years ago after the original 1986 Ford moveable pole piece one died. I did have to replace it about a year ago, and was able to obtain another Precision Certi-Pro one locally. Pasco out of Salisbury MD bought the Precision line when they went out of business.
Bill AKA "LOBO" Profile

"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413

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