My electric chokes were working perfectly before the engine change. Of course, after I got the new engine in, I thought I'd check them. When I turn the key, the electric chokes are working but it's taking a long time for them to open. Is this because the battery is worn from sitting so long? I guess I could try them with the battery charger on the battery...

This happen to anyone else?

BG

My electric chokes are marked with 45 amps, do they really pull that much amperage? Anyhow, I'm using the same wire as I used before the engine change, so I'm perplexed as to why the chokes are taking so long to open. I've heard if one's battery isn't putting out a full 12v this could happen. Maybe I'll try again with the battery charger on the battery.

OK, the entire symbols on the electric choke are:

170W45A

1F 12A

2KT44-2C

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I don't see any decimal points in the numbers on the electric chokes. I measured the resistance, I get (if I'm reading the meter correctly) about 5 ohms resistance for the chokes.

What is the amperage draw of these chokes?

BG

tells me at 12v and 5 ohms, I have 2.4 amps draw. BUT, I tried a 10 amp fuse (two chokes, so about 5 amps draw) and the fuse burn out. I tried a 30 amp fuse and it held, didn't burn out, but the chokes still take a long time to heat up and open...

How are the chokes wired, in series or parallel?
Are they powered off of blue wire from ignition switch?

Best method of powering electric choke is via a relay direct from battery triggered from blue wire; this will keep voltage level up enough at coil for decent spark.

Two chokes are required to be wired in parallel so each unit sees nominal 12 volts. If you have chokes in series there is a voltage drop across each bimetal coil, and slow opening results.

Lastly these devices need a good ground with no voltage drop back to negative battery terminal.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Yes, they were wired with the blue wire, with one wire leading to a Y, each leg of the Y going to an electric choke. The thing is, this was working before the engine change...and they do still open, just ever so slowly now.

Anyhow, I can run a relay with direct power from the battery, but I don't know how much amperage these things are pulling. It can't really be 45A each that's ridiculous (isn't it?), so I must be reading the label wrong, perhaps that's the maximum rating before failure? Since the 30A fuse didn't fail, they must not be drawing (collectively) more than 30A otherwise it would fail. So, I figure a 30A relay should be OK.

I'll hook up a relay and get that battery fully charged up (I thought it was, but perhaps not).

In the meantime, does anyone make sense of the labeling on my chokes, see above. I used an old style ohm meter to measure the resistance so that reading might not be good. I'll recalibrate it and try again, but assuming it's ballpark, these chokes are only pulling a few amps each (which to me makes sense). If it helps, these are 32/34 DFT Weber two barrels; I can't seem to find anything in the specs that say what the chokes pull.

BG

BTW, does anyone know about how much current a relay draws? It should be very little, but what size fuse should I use between the blue wire and the relay to trip the relay? I don't see that on the relay I have, may be it's on others. I see the amp rating for what the relay will carry across 30/87, but not how much it draws at 86/85 poles to close it.

BG

Just measure resistance of 86-85 coil, plug 13 volts into this calculator; it ain’t going to be much which is the point of using a relay. One relay can power both chokes.

Resistance of choke coil (mine anyway) is around 8.7 ohms, using I=v/r I= 13v/8.7ohm I= 1.5 amps

Caution atrophied (atrofried or abbynormal) old brain in use most of the time.

Sorry I got a typo integrated into the earlier explanation, and left out the second step where total resistance is plugged into 13 v average system voltage.
You will find current draw of relay coil (85-86) is 13v/82.9ohm = 0.157amps; in other words, next to nothing.

This describes parallel configuration; good. Check for poor grounding as voltage drop in ground side of circuit would be additional resistance added to this circuit as a series load; not good.

By any chance did the feed wire to chokes get landed on the low voltage side of the ballast resistor? If this is the case, chokes are getting only 6 to 8 volts which would considerably slow their response.

Once choke load is off of blue ignition wire, ignition coil will see better voltage, and some of voltage drop will be eliminated in that circuit which will help normalize charging voltage level.

This is how I rewired my choke feed:

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

1/2 to 1 amp is more than enough

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

According to my multimeter, my chokes are like 7-8 ohms as well, so maybe its the ground (although I tried a 10 amp fuse in the line and it blew that instantly). The chokes should be grounded to the engine via the bolts from the manifold to the carbs, but I'll check for sure.

I don't run a ballast, I have a pertronix coil with a built in resistor...

It looked like the blue wire was delivering about 10-11 volts though, so maybe the chokes aren't getting a full 12v for some reason. Again, I'll check the grounds and try again with a full battery charge and the charger on the battery just to make sure...

Also...I did add a relay to the blue wire to run an auxiliary fuse panel, it has a 5 amp fuse, so maybe...I need to drop that down to a 1 amp fuse since it doesn't need the 5 amp. But if the relay is drawing a fraction of an amp, the 5 amp fuse in the line shouldn't draw extra current away from the blue wire, since it's the relay that's drawing, not the fuse, right?

Anyway, I think another relay for directly powering the chokes is a good idea no matter what I find out.

bg

Brain fart Department correction:
First off I have edited my calculations in previous post to reflect chokes in parallel; I don’t know why I did what I did…
You have voltage drop problem, blue wire should be close to battery voltage without chokes connected.
Yes in theory they are connected and electrons flow, but unless the path back to negative battery terminal is voltage drop free, in other words, no additional resistance is present, things are not going to work correctly. Check connections of negative battery post to block, and head to fire wall ground connections.

I get about 5 amp draw so a 10 amp fuse should work just fine.
13v/{1/8.7 + 1/8.7} = 13/{.115 +.115} = 13/.229 = 4.36A
Could be there is a short internal to one of the bimetal coils causing fuses to blow, or something is amiss internal to choke from carb rebuild. You need to do some testing, and or disassembly of chokes to be sure everything is articulating correctly.

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

I don't think it's the chokes, I didn't rebuild the carbs, they're fairly new and they were working perfectly before I pulled the engine, must be a voltage drop somewhere..they do work, they just heat up slowly and then open as they should.

bg

Seems like a high resistance in the choke to ground (battery negative terminal) path, as was mentioned. I'm not familiar with those carbs, but the chokes are integral to them, right??
If so, the ground path to the battery is carbs to manifold to engine block to battery negative. But you knew that!

I'm wondering if there is some resistance at the junctions along that path. Are all of them clean and tight? What is the resistance from the battery negative post to the carbs?
You're closing in on it, and inquiring minds want to know.

BC

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'64 Dart GT convertible, 64 Dart 170 2-door post sedan in faded blue and rust (the Az Dart) & a sixty THREE Dart 170 2-door post sedan in faded blue and rust. (future project)
Early Dart Disorder (EDD) is real, and I've got it!