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> wiring up the engine
JFG
post Aug 17 2017, 02:54 PM
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My car came minus most things in the engine area, including the engine & tranny. I have no point of reference to work back from.

Tonight i made a new alternator harness and wired that in. I think the starter motor wire from the battery is routed over the tranny so i've just looped that over for testing.

I have a new 34 svda distributor to fit which has a black wire and a red wire (electric module not points). I also extended the existing fuel pump wires in order to run the new pump up front under the tank from the existing ignition / relay design.

Now all i have is one green wire which i believe is for the head temp sensor.

There are no other wires in the engine bay. So what wires are missing to successfully wire up and run the engine?

The starter has only the battery cable & alternator cable fitted to number 30? Connector, the spades are empty. The coil has nothing connected to it. The relay board has the main loom connected and all relays are present.

It'a 74 2.0 running twin 40idf's. I cannot read electrical diagrams such as what ypu find in haynes manuals etc.
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Spoke
post Aug 17 2017, 03:35 PM
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Pics of the engine bay would help.

If carbs, you don't need many wires:

o +12V for the coil
o Wire for oil pressure switch
o Wire for tachometer (off of coil negative side)
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JFG
post Aug 17 2017, 11:56 PM
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Where would the +12v come from for the coil? I'm assuming not direct from the battery!

I've already been through the loom and there are no wires free that would have gone to the oil pressure switch. I can run a wire from neg to the rev counter (just about).

What colour should oil pressure switch be, green? As it's not there what would be the way to add a fresh wire to complete the circuit?
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IronHillRestorations
post Aug 18 2017, 05:52 AM
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You have to make a jumper to get the fuel pump to work with the stock relay, as that relay is triggered by the injection system.

Did an engine harness come with the car?

Oil pressure switch wire is green with red tracer.
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Spoke
post Aug 18 2017, 06:58 AM
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+12V for the coil comes from the ignition switch. As far as colors of wires, check a repair manual for color codes on wires or on Pelican Parts for their online schematic/wire diagrams.

Is there a relay board in the engine compartment? Pics would help.
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JFG
post Aug 18 2017, 09:54 AM
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The only harness was the main plug to the relay board, the group of lives to the battery, the fuel pump & head temp switch. There are no other wires in the engine bay. I've seen the jumper how to for the fuel pump. Just need to sort a switched live for the coil & how to wire the pressure switch.
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JFG
post Aug 18 2017, 11:53 AM
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On further inspection & realisation I also don't have reverse switch wiring! (IMG:style_emoticons/default/headbang.gif)

With regard to the coil, could I take a switched live from the relay board? Either from t4b or t12? The ground comes from t4b to trick the board into allowing live through to the pump so I don't really want to come off there if I can avoid it.

Jeff bowlsby drawing shows the pins which would have been originally in the harness.

1 oil pressure sender
5 coil - (do I need this with carbs?)
7 coil live
2&4 back up lights
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JeffBowlsby
post Aug 18 2017, 07:17 PM
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Why not just get an ignition harness? It has all that you need. It also has the heater fan jumper, back up light switch. Oh, and the starter.
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JFG
post Aug 20 2017, 07:07 AM
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I've sourced a new 12 pin switch so I can make my own harness for the missing wires.

Can someone tell me what the yellow solenoid wire to the starter is rated at? Is 25 amp 2mm thin wall 28/0.30 sufficient?
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stugray
post Aug 20 2017, 08:56 AM
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QUOTE(Perry Kiehl @ Aug 18 2017, 05:52 AM) *

You have to make a jumper to get the fuel pump to work with the stock relay, as that relay is triggered by the injection system.

Did an engine harness come with the car?

Oil pressure switch wire is green with red tracer.


I sincerely HOPE the OP knows to NOT use the stock fuel pump in this setup?
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JFG
post Aug 20 2017, 10:23 AM
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[/quote]

I sincerely HOPE the OP knows to NOT use the stock fuel pump in this setup?
[/quote]

I do indeed, as i am fitting twin 40 idfs i have a low pressure fuel pump (IMG:style_emoticons/default/beerchug.gif)
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