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> Relay Board - 73, what should this look like?
seanpaulmc
post Feb 8 2018, 12:17 PM
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Here is a picture of the engine compartment Relay Board of my '73. Will someone post a picture of what this should look like?

I've had the car for a short time and am learning about all the wiring work arounds. Note the car is running carbs. Three things I'll point out in this picture are:

1. The ignition harness coming off the board has a red crimped connector in it. Might need one of Jeff's new harnesses (?).
2. The brown (ground) wire on the left bottom is unconnected. Where should it run to?
3. Bottom right of photo is a blue wire coming from under the dash - will deal with in a later posting. Not in the photo, the ignition key has been bypassed with a push button installed on the dash. Still needs key in and on to start.

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914Sixer
post Feb 8 2018, 12:57 PM
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The relay board itself is correct. Lots of extra going on as you noted.
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1adam12
post Feb 8 2018, 01:36 PM
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Bottom left where you have that brown wire coming out of was a connection of (4) white wires from the original FI harness. 4-Pole connection for injection harness.
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SirAndy
post Feb 8 2018, 01:48 PM
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QUOTE(seanpaulmc @ Feb 8 2018, 10:17 AM) *
what should this look like?

A lot cleaner ...
(IMG:style_emoticons/default/FERG.gif)
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malcolm2
post Feb 8 2018, 01:50 PM
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http://bowlsby.net/914/Classic/TechNotebook.htm

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14 pin connector drawing is also on Bowlsy's link above.
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SirAndy
post Feb 8 2018, 01:52 PM
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QUOTE(seanpaulmc @ Feb 8 2018, 10:17 AM) *
2. The brown (ground) wire on the left bottom is unconnected. Where should it run to?


Looks like someone was trying to do the correct thing and use the stock fuel pump location and wiring for the new low pressure carb fuel pump.
In which case that brown wire should be connected to ground.

http://www.914world.com/specs/SirAndyCarbFuelPumpRelay.php

Not sure which terminal that goes to on yours, kinda hard to see and i'm not sure if all of those 4 terminals work the same way, but if you follow the link above it shows what i did on my carbed 2056 to retain the stock fuel pump wiring when converting to carbs.
(IMG:style_emoticons/default/shades.gif)
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gothspeed
post Feb 8 2018, 02:34 PM
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Andy, Is there a reason this lug is not in the connector?

(the yellow arrow)


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SirAndy
post Feb 8 2018, 03:44 PM
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QUOTE(gothspeed @ Feb 8 2018, 12:34 PM) *
Andy, Is there a reason this lug is not in the connector?
(the yellow arrow)

Yepp, wrong year engine harness ...
(IMG:style_emoticons/default/biggrin.gif)
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JeffBowlsby
post Feb 8 2018, 03:48 PM
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QUOTE(gothspeed @ Feb 8 2018, 12:34 PM) *

Andy, Is there a reason this lug is not in the connector?

(the yellow arrow)


The 12 pin connector should only have one green wire in it...so I have no idea what the two green wires are or should be connected to in your photo. You would need to open up the connector and trace the wires to see where they go.
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SirAndy
post Feb 8 2018, 09:15 PM
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QUOTE(Jeff Bowlsby @ Feb 8 2018, 01:48 PM) *
QUOTE(gothspeed @ Feb 8 2018, 12:34 PM) *
Andy, Is there a reason this lug is not in the connector?
(the yellow arrow)

The 12 pin connector should only have one green wire in it...so I have no idea what the two green wires are or should be connected to in your photo. You would need to open up the connector and trace the wires to see where they go.

The other one is (was) green/black. It's an early D-Jet engine harness but my cars main harness is from a '74 so i unhooked the solid green wire since it otherwise would go to the bottom relay (heater blower).
The green/black wire is also not used on a '74 but i could leave that in the plug since it isn't connected to anything on the other end of the relay board (There's an empty spot in the other connector/harness on later cars)
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gothspeed
post Feb 8 2018, 11:58 PM
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QUOTE(SirAndy @ Feb 8 2018, 01:44 PM) *

QUOTE(gothspeed @ Feb 8 2018, 12:34 PM) *
Andy, Is there a reason this lug is not in the connector?
(the yellow arrow)

Yepp, wrong year engine harness ...
(IMG:style_emoticons/default/biggrin.gif)
cool, thanks. I thought the loose lug was part of the harness conversion for carbs (IMG:style_emoticons/default/popcorn[1].gif)
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JeffBowlsby
post Feb 9 2018, 10:25 AM
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QUOTE(SirAndy @ Feb 8 2018, 11:52 AM) *

QUOTE(seanpaulmc @ Feb 8 2018, 10:17 AM) *
2. The brown (ground) wire on the left bottom is unconnected. Where should it run to?


Looks like someone was trying to do the correct thing and use the stock fuel pump location and wiring for the new low pressure carb fuel pump.
In which case that brown wire should be connected to ground.

http://www.914world.com/specs/SirAndyCarbFuelPumpRelay.php

Not sure which terminal that goes to on yours, kinda hard to see and i'm not sure if all of those 4 terminals work the same way, but if you follow the link above it shows what i did on my carbed 2056 to retain the stock fuel pump wiring when converting to carbs.
(IMG:style_emoticons/default/shades.gif)


Makes sense. The large green disconnected lug is power for the heater fan. The inner green/black is for the oil temp sensor on the 1970-71 cars.
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gothspeed
post Feb 9 2018, 02:15 PM
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QUOTE(Jeff Bowlsby @ Feb 9 2018, 08:25 AM) *

QUOTE(SirAndy @ Feb 8 2018, 11:52 AM) *

QUOTE(seanpaulmc @ Feb 8 2018, 10:17 AM) *
2. The brown (ground) wire on the left bottom is unconnected. Where should it run to?


Looks like someone was trying to do the correct thing and use the stock fuel pump location and wiring for the new low pressure carb fuel pump.
In which case that brown wire should be connected to ground.

http://www.914world.com/specs/SirAndyCarbFuelPumpRelay.php

Not sure which terminal that goes to on yours, kinda hard to see and i'm not sure if all of those 4 terminals work the same way, but if you follow the link above it shows what i did on my carbed 2056 to retain the stock fuel pump wiring when converting to carbs.
(IMG:style_emoticons/default/shades.gif)


Makes sense. The large green disconnected lug is power for the heater fan. The inner green/black is for the oil temp sensor on the 1970-71 cars.

Jeff, I'm doing carb conversion on my 73'. Does the ignition harness need to be modified? or some pins not used?
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JeffBowlsby
post Feb 9 2018, 03:58 PM
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QUOTE

Jeff, I'm doing carb conversion on my 73'. Does the ignition harness need to be modified? or some pins not used?


Use it as is. Only the AAR branch (white wire) will not be used.
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SirAndy
post Feb 9 2018, 05:06 PM
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QUOTE(Jeff Bowlsby @ Feb 9 2018, 01:58 PM) *

QUOTE
Jeff, I'm doing carb conversion on my 73'. Does the ignition harness need to be modified? or some pins not used?

Use it as is. Only the AAR branch (white wire) will not be used.

If i remember correctly that wire is always hot, so make sure you have it properly insulated.
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gothspeed
post Feb 9 2018, 07:59 PM
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QUOTE(Jeff Bowlsby @ Feb 9 2018, 01:58 PM) *

QUOTE

Jeff, I'm doing carb conversion on my 73'. Does the ignition harness need to be modified? or some pins not used?


Use it as is. Only the AAR branch (white wire) will not be used.

Awesome, thank you for the info (IMG:style_emoticons/default/smile.gif)

QUOTE(SirAndy @ Feb 9 2018, 03:06 PM) *

QUOTE(Jeff Bowlsby @ Feb 9 2018, 01:58 PM) *

QUOTE
Jeff, I'm doing carb conversion on my 73'. Does the ignition harness need to be modified? or some pins not used?

Use it as is. Only the AAR branch (white wire) will not be used.

If i remember correctly that wire is always hot, so make sure you have it properly insulated.
(IMG:style_emoticons/default/shades.gif)
Good to know, I will test it to verify. Maybe I can use it for something ... (IMG:style_emoticons/default/idea.gif)
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Dave_Darling
post Feb 10 2018, 02:06 PM
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QUOTE(SirAndy @ Feb 9 2018, 03:06 PM) *

If i remember correctly that wire is always hot, so make sure you have it properly insulated.
(IMG:style_emoticons/default/shades.gif)


It is only hot when the fuel pump is running; it gets its power from the fuel pump circuit and is fed by the fuel pump relay. If you're using the stock relay, insulating the connector would be a Super Good Idea ™.

--DD
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