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AAW 1974 coil wiring question

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AAW 1974 coil wiring question
#1
  This topic is about my 1974 Triumph TR6
ChoukyB Avatar
ChoukyB Serge Decorte
San Diego, CA, USA   USA
Hi to all,

need help on how to properly wire my coil following AAW wiring for my 1974 TR6.

First question is where are the + and - terminals on that coil diagram.

2nd: The diagram shows a 12G White coming from the power block with a ballast going to the coil. My coil is a Lucas and it mentions that a ballast resistance of 1.3 to 1.8 ohm is required. It was not provided by AAW, (I believe) . What does it look like and where can you get one?

3rd question: diagram shows a WN ( white brown) wire going from the starter to the coil ( if required). How do you know if it is required?

Thank you for any input.

Serge

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TR3driver Randall Y
Confusion, Los Angeles, USA   USA
"+" terminal gets power from ignition switch; "-" terminal goes to points.

Ballast resistors are readily available from the usual suspects, or almost any auto parts store. I bought one a few months ago from a NAPA in a town of less than 1000 people (tho I did get charged several times as much as TRF). TRF P/N is 134176A

The idea is that the WN wire is "required" if you use a ballast-type coil and resistor. It isn't actually required IMO, but may help with easier starting in very cold weather or if the plugs are fouled for some reason. Having a ballast but not the WN is electrically equivalent to using a "non-ballast" coil as almost all cars did until the early 70s.



Randall
56 TR3 TS13571L Once and future daily driver
71 Stag LE1473L awaiting engine rebuild
7? Stag awaiting gearbox rebuild

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Tonyfixit Avatar
Tonyfixit Tony M
Duncan, BC, Canada   CAN
As Randall says. But what is AAW?

Is this a new coil? If so is it a 7v requiring a resistor? often this takes the form of a pink and white wire. See picture.



Edited 1 time(s). Last edit at 2019-03-06 01:53 AM by Tonyfixit.

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TR3driver Randall Y
Confusion, Los Angeles, USA   USA
AAW is Advance Auto Wire http://www.advanceautowire.com/
Founded by Dan Masters; but I can't think of the name of the gentleman who took over when Dan retired.

The AAW harnesses do not incorporate a ballast resistor wire. If a ballast is needed/desired, it can be added as a separate part. Even the harness is more what I would call a "kit", since the wires are not trimmed to length nor have connectors installed.

Coil "voltage" gets confusing, since many of them are marked things like "12v - Ballast required".

In reply to # 1600355 by ChoukyB My coil is a Lucas and it mentions that a ballast resistance of 1.3 to 1.8 ohm is required.

Good enough for me.



Randall
56 TR3 TS13571L Once and future daily driver
71 Stag LE1473L awaiting engine rebuild
7? Stag awaiting gearbox rebuild

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ChoukyB Avatar
ChoukyB Serge Decorte
San Diego, CA, USA   USA
Thanks Randall,

I think that I am still a bit confused. Sorry, it has been 40 years since I dealt with car electrical system .

Just want to make sure I got this right : the coil + terminal receives the WN wire from the starter and the W wire from the power relay via the ignition.
The - terminal receives the WB wire to the distributor.

Could not find the TRF P/N you provide nor from the usual supplier but Napa has one : https://www.napaonline.com/en/p/MPEICR13SB.
That ballast resistor is on the + side according to AAW, but reading on the web, some mention to connect to the - terminal. So, a bit confused.

Serge

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poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
If you are going to reduce the voltage feeding the coil when the engine is running from 12 volts to less, then you need to use the ballast on the wire feeding the coil when the engine is running. In this case it would be the W wire from the ignition.



ZS carb repairs
kencorsaw@aol.com

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ChoukyB Avatar
ChoukyB Serge Decorte
San Diego, CA, USA   USA
Hi Ken,

thanks for jumping in,

just to be sure : the W wire with the ballast goes the + side terminal of the coil. Correct?

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Tonyfixit Avatar
Tonyfixit Tony M
Duncan, BC, Canada   CAN
Yes. The W wire from the ignition switch goes to the ballast resistor, then out from the ballast to the + on the coil.

The WN wire goes from the starter solenoid directly to the + terminal on the coil.

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poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
Right !
The W/N wire feeds the coil 12 volts when you're using the starter with the ignition key twisted to START
The (ballasted) W wire will begin to feed the coil once the ignition key has returned to the RUN/ON position.
Both wires will be on the coil + terminal.

There is a way to eliminate the ballast, but you'd need to replace the coil with a 3.0 ohm coil.



ZS carb repairs
kencorsaw@aol.com

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ChoukyB Avatar
ChoukyB Serge Decorte
San Diego, CA, USA   USA
Awesome, thank you both for your input. Very helpful.

Serge

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TR3driver Randall Y
Confusion, Los Angeles, USA   USA
Sorry, my mistake. I just assumed Moss would have it https://www.moss-europe.co.uk/resistor-coil-ballast-134176a.html



Randall
56 TR3 TS13571L Once and future daily driver
71 Stag LE1473L awaiting engine rebuild
7? Stag awaiting gearbox rebuild


Attachments:
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UNTITLED.JPG

PAGES FROM DAN MASTERS POWERBLOCK 73-76 TR6-2.JPG    13.1 KB
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NHinNC Avatar
NHinNC Larry C
Greensboro, NC, USA   USA
I am sorry if I am saying something that is understood, but there is no "resistor" in the original parts, it is that the wire itself is a resistor wire. So, if you are looking for a discrete resistor component, you will not find it. With the key in the run position, one can measure the resistance back to the +12V terminal. I would recommend pulling the + terminal wire and measure the resistance from the wire to be connected to the coil, to the +12 battery clamp.



1976 TR6 Mimosa Yellow - not original
Purchased July 2015

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modandrocker Steve N
Greensboro, NC, USA   USA
it is that the wire itself is a resistor wire. So, if you are looking for a discrete resistor component, you will not find it.
As Larry has said is correct. The factory Resistor Wire is covered with the factory cloth woven loom wire. There is no other one like it and denotes that this wire is a Resister Wire. It will give you power from the Ignition switch to the + Coil.

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poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
That's correct if you're talking about the original wiring for the post 72 TR6's...but I think we're dealing with the Advanced Auto Wiring (AAW) harness.
Do you know if the AAW harness that Serge has have a resistor wire or is it as Serge has been advised needing to provide a resistor for his 1.5 ohm coil ?



ZS carb repairs
kencorsaw@aol.com

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TR3driver Randall Y
Confusion, Los Angeles, USA   USA
Well, no, not in this case. Serge is installing an Advance Auto Wire harness kit, which does not include the resistor wire. As supplied, it has only a standard copper core wire supplying power to the region of the coil. It can be installed with or without a resistor (depending on which coil and ignition you use), but if you want a resistor, you have to supply it yourself. It doesn't come with the kit.

It's too bad Dan didn't explain this better; I assume he felt it was obvious. But you can read what there is about the AAW kit at
http://www.advanceautowire.com/



Randall
56 TR3 TS13571L Once and future daily driver
71 Stag LE1473L awaiting engine rebuild
7? Stag awaiting gearbox rebuild

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