Carburetors

Mikes5thAve

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It's been a while but I think the other side runs thru the oil pressure switch so that it's not getting power when the engine isn't running.
 

BudW

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I made these yesterday, but forgot to attach 'em. These are from my '77 FSM (Factory Service Manual) but is similar for other years, including those with computer on air cleaner versions.

Here, it is called the Electronic Choke Control and it is on the bottom of page 8-248 - but the feed wire J2 14DBL (14 gauge dark blue wire) goes to the next page (and back).

I don't know how I forgot the attachments...
BudW
 

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  • 77 FSM 8-248.pdf
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  • 77 FSM 8-249.pdf
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Mikes5thAve

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P_20210409_133654.jpg

This is how the 80s ones connect which is what I do with no computer.

My 79 was somewhere in the middle. Didn't wire up like 77 but still had the solenoid and egr timer stuff.
 

BudW

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the OP doesn't mention what vehicle he has, but his second post says he has a '78 Lebaron.
Deano might want to put his year/model in his signature for future reference.

I agree the early '80's (on) does have the choke wired that way, but I didn't bring it up due to the year of his car.
In his case, he would need to invest in a new oil pressure sender to get it to work (more unnecessary work & expense).

Mike, I wasn't trying to mislead anyone, only trying to tailor my answer to his car type - but a bit more explanation on my part might have been more helpful.
BudW

Edit: My '77 has the EGR timer but no carburetor solenoid. According to the attached PDF's, the solenoid was only for /6 & 318 2-bbl A/T California cars.
 

Mikes5thAve

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I think you're right on the year, one pic has the old style master cylinder for brakes.

He said he's converted to electronic ignition so hard to know what other parts are still there or working and the way this post is jumping all over the place with the different parts for different years i thought I'd include it. Since it seems like some of the wiring might be missing at least it shows a simpler way of hooking it up avoiding some of the extra parts. I think it can can tie into the other (non dk blue) side of the oil pressure switch to power it without having to replace the switch or plug.

Edit: actually no, it can't connect to that second side.. At least I think it does the opposite and the one side gets power thru the oil pressure switch when engine isn't running (or low oil pressure) to turn on the oil light and the 3rd prong the choke goes to gets power when it is running.
 
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BudW

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It is kinda odd, Most of the F-bodies came without a computer (but that percentage was growing sharply by '80), while most (almost all) of the M-bodies came with a computer (only a handful left without a computer, except for those destined for outside of USA).

The three-wire oil pressure switch wiring is different from the single wire oil pressure switch, which he has. If he tapped into his oil pressure switch wiring, his dash oil light would be on pretty much anytime the car is turned on (see attached), or more exactly, anytime his choke heater is turned on.
That said, I do agree with you on the early '80's cars (and newer), but not in his case.
 

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Mikes5thAve

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That's what my edit was.
I just noticed now that the oil pressure switch is the kind that has a single connection that grounds to turn on the light. For some reason I thought it was the 2 wire kind that runs power thru it. Not that it matters in this case but the 3 wire pressure switch my wiring is for started in 79.
 

Deano

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I do have a '78 ESM, but there are times that I'm kinda confused/overwhelmed by what I'm looking at. The wire that connects to the terminal opposite of the one from the choke thermostat is from a switched source, right? Gets power only when the ignition is turned to "run". Don't really know how to explain it, so here's a pic of what I'm trying to get at.

DSCN4312-1.jpg
 

BudW

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The Thermoquad 4-bbl has a bent arm. The BBD and Holley 2280/6280 are straight (but different lengths).
The bi-metallic spring is the same, so if you can't get the correct thermostat, just get one for a another (similar year) Chrysler, and transfer the new bi-metallic spring to your existing housing/rod.
 

Deano

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Both rods (new and old) seem to be the same length. I wasn't sure if one should be longer than the other.
 

BudW

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One 2-bbl thermostat rod is about 1/4" longer than the other one. I "think" the Holley 2280/6280 is the longer one (going by memory, which might not be correct).

Your car should have had the Carter BBD on it originally. I see from your pictures, earlier posts, you do have a Holley 2280. I have a strong suspicion that someone didn't install the Holley version thermostat on it, at same time - which could be a good reason why one is having carburetor issues.

The Carter thermostats most likely don't say anything, except for a few numbers stamped on it.
The Holley thermostats do have "Holley" stamped on them, and some numbers.
That said, the bi-metallic spring wears out every 10-15 years of normal usage anyway, and I can tell by looking at your thermostat, it is well over 15 years old (and most likely original to the car).
DSCN4300.JPG

BudW
 
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