adding a wire for my electric choke.

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moparmat2000

moparmat2000

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Hi Y'all,

I am in the process of modifying my engine compartment harness to add in an 8 gage wire for my denso 50A alternator, finish my ammeter bypass circuit on the engine side, etc.

2 questions, My new alternator being an internally regulated denso type, i bought a denso style plug to wire it in. This plug has 14G wire pigtails for the ignition exciter. My ignition feed wire in the harness is 16G wire. Since i havent wrapped up my wiring yet should i upgrade this alternator sense lead in the harness to the heavier 14 gage.?

My second question is, can i tap off this ignition switched hot lead that goes to the alternator to run an electric choke, or will this cause a problem with the alternators internal voltage regulator??

Thanks
Matt
 
I use a piggyback spade terminal and jump off the input side of the ballast resistor. It usually has the two dark blue wires, but disconnect both wires at the ballast resistor, turn the key to the run position, then poke in there with a test light to see which one has power... Then use that one to run the positive wire for the electric choke. I've been running them for decades that way with no problem...
 
krazykuda said:
i use a piggyback spade terminal and jump off the input side of the ballast resistor. It usually has the two dark blue wires, but disconnect both wires at the ballast resistor, turn the key to the run position, then poke in there with a test light to see which one has power... Then use that one to run the positive wire for the electric choke. I've been running them for decades that way with no problem...
Click to expand...

x2
 
On your exciter lead, you might want to do some research. If this alternator is designed for an "idiot light" all the older GM stuff was supposed to have a lamp or resistor in the excite wire. YOU CAN also use a diode

Now I "ain't" up on all the new stuff so make sure you check this out

AlternatorHarness3.jpg


cs130.jpg


C130D_wiring.jpg


21757d1131915214-how-do-you-like-my-home-made-generator-alter001.jpg
 
I did not intend to use the L terminal on the back of the alternator which is for the idiot light. The only terminals i'm using are the IG terminal which is ignition hot, and the output terminal with my 8 gage wire.

The leads for the old VR on the firewall i am just going to hook together to eliminate the old external voltage regulator.

Should i use a bigger 14G wire for my denso sense wire?

Matt
 
You might also consider using the Chrysler electric choke control in the hot wire lead to the electric choke. This cuts power to the choke thermostat after the choke heats up. It keeps the choke thermostat from becoming brittle and possible melting over time. You can find them on Ebay pretty reasonably. It's a nice feature to have.
 
moparmat2000 said:
I did not intend to use the L terminal on the back of the alternator which is for the idiot light. The only terminals i'm using are the IG terminal which is ignition hot, and the output terminal with my 8 gage wire.

The leads for the old VR on the firewall i am just going to hook together to eliminate the old external voltage regulator.

Should i use a bigger 14G wire for my denso sense wire?

Matt
Click to expand...

Sorry I'm just not all that "UP" on the new Denso stuff. The sensing wire would depend on whether it's "only" for excite / sensing........in which case there's no real current flow.........or whether that line also actually powers the VR, like the Mopar electronic ones.

You'll have to check this out. Wish I knew but there are so many "newer" alternators I don't have a handle on them.
 
It may be helpful if you supplied a part number or link to the alternator you purchased. Is this to be used on a street car or race car?
 
RustyRatRod said:
You might also consider using the Chrysler electric choke control in the hot wire lead to the electric choke. This cuts power to the choke thermostat after the choke heats up. It keeps the choke thermostat from becoming brittle and possible melting over time. You can find them on Ebay pretty reasonably. It's a nice feature to have.
Click to expand...

Thanks RRR. Learn something everyday. Is this a good idea with any electric choke? I have an electric conversion for a /6 single barrel and have one of these laying around..

View attachment Choke Control.jpg

never paid any attention to the things before. Nice to know what they do...
 
Street car 50A output max. Mini denso. 3 wire. IG ignition hot to regulator, L ignition lamp / fault lamp, power output stud. Dont have a part number handy sorry.

The harness i am modifying is a new 67 barracuda engine compartment harness. This setup did not come with electric choke, i like rustys idea of using the choke thermostat. Still i need to add the wire into the harness.

My carb is a carter 625 AVS with electric choke. It makes no mention of this type of device to go with the electric choke. Just says to wire it to an ignition switched hot. This being said not sure if an electric choke thermostat is needed.

Does the choke thermostat get wired in series going to the thermostat on the carb? Is it also case ground? Anybody know if i can just tap off the ign hot lead that goes to alternator sense wire (green)

Thanks
Matt
 
It seems like a bi-metalic thermal cutout switch could be wired in series and placed in the intake choke thermal well. A relay could be used if you would like to avoid loading switched IGN circuit. I did a quick Google and found some typical thermal cutouts here.http://www.electronicsurplus.com/sensors/temp-switch-thermostat
Seems like about 180F would work. Might want to verify well temperature with oven thermometer to get an idea of well temperature with car warmed up. Also verify that choke bi-element opens choke fully when car is warm. If not, it might need the choke heater all the time, or a resistor in parallel with switch. The resistor would reduce the current to provide just enough heat. Then you would be similar to OEM choke controller.
 
^Vote for best post. Those damn electric chokes ALWAYS close too soon and open too fast when directly connected to 12v. They need a resistor or something wired in.
 
I was reading somewhere that GM used a relay wired in so that when ignition was switched on but the car not started the elect choke would not get power to open. I think it was wired into the alternator circuit somehow, and would only get power for the relay, to energize if alternator was online, which would only be if the engine was running. Anybody else know about this one. Sounds like a good idea.

Matt
 
I do that kind of thing with the micro controller in my ignitions and engine management systems. Power relay is kept alive if timing sensor signals are present, if not the power is disabled. Power enables again if sensor signals return.

I am only familiar with Bosch alternators with internal regulators, the warning indicator could be used to drive a NC relay. If engine is stalled, the indicator circuit would disable power. The Bosch needs a 2W load powered by swiched ignition supply. The indicator circuit, triggers the alternator to start generating after a short delay. Without lamp, the delay can be long, or it may not trigger.
 
moparmat2000 said:
I was reading somewhere that GM used a relay wired in so that when ignition was switched on but the car not started the elect choke would not get power to open. I think it was wired into the alternator circuit somehow, and would only get power for the relay, to energize if alternator was online, which would only be if the engine was running. Anybody else know about this one. Sounds like a good idea.

Matt
Click to expand...

Why would you leave the key on with engine not running? Several types of ignition systems can be damaged doing so, including breaker points, Mopar breakerless, and Pertronix.
 
I added a fuse in the unused fuse terminal in fuse block key on live. Then fed it through the now unused alt spot in the fire wall plug. Would not be hard to add resister to slow down choke. Tried field wire so engine would have to be running but that started cooking battery terminal.
 
Ben Drinkin said:
Thanks RRR. Learn something everyday. Is this a good idea with any electric choke? I have an electric conversion for a /6 single barrel and have one of these laying around..

View attachment 1714847412

never paid any attention to the things before. Nice to know what they do...
Click to expand...

Yes, I consider it a good idea with any choke. It helps keep the choke thermostat from overheating and getting brittle and even melting over time.
 
I don't know about the Denso alternator you are using, but I know the older GM type, since used in my 1985 M-B. Those are the "Motorola design" and have an "excite" wire that goes to one or more dash bulbs. That wire needs a current inflow (from BATT+ - key - bulb) into the alternator "excite" (D+ in my Bosch alt). That slight current "boots up" the internal "field generator". Once that boots up, the current flow stops (bulb goes out). If the dash bulb(s) fail, the alternator doesn't ever boot up and thus output. I found this when I replaced w/ LED bulbs. An old alt may boot-up at higher rpm from residual magnetism.

I think the Denso alternator in my 1996 Plymouth has the same basic design as in our old cars, i.e. an external Vreg (inside the PCM). Perhaps not all Denso's work the same.
 
I will have to do more research. I currently have the engine / forward lamp harness lying in the engine compartment routed correctly, and have wire twist ties holding the bundles together as i removed the vinyl wrap. This is a brand new harness from year one that i am putting upgrades into so as soon as i get it how it needs to be i will be rewrapping it with the correct non sticky vinyl harness wrap.

I have my 8 gage alt wire routed, and my 2 feed wires at the bulkhead for my ammeter bypass done. Just gotta figure out the renso setup, route my choke feed wire, and maxifuse everything coming out of the battery. Then i will need to start on the headlamp relay setup, and wire in a relay for an electric radiator fan.

Matt
 
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