Here's the choke/carb on my g/f's 1986 Iroc 305.... something is not adding up.. I have no idea about carbs, and have tried to adjust the carb according to the Haynes manual, and some mechanic websites. It wants to run at 500RPMS or below, and the car either dies out, or diesels because of this.

(Auto carb)

 

I didn't get a pic inside, but the arm is actually all the way to the bottom "dot" or a little bit past it. I thought it was supposed to be at a 12'oclock setting. (in between the dots)

 

Butterfly valve position w/ the car off, on, or running. All arms, etc are not obstructed, or broken. Car also backfires.

 

I would guess that either a) the thermostat tang is not engaging the tab when installed (having only two of the three pop rivets drilled out and replaced with screws could contribute to that), or b) the thermostat is not heating up - either no power is getting to it, or it is open electrically.

Just guessing.

 

Thermostat tang? I'm not sure what that is... anyone got a pic?

 

it sounds to me like your timing is off that the only thing that would cause the car to sound like a diesel. when you timing is to advanced the car will back fire thorw the intake and should like a diesel when you give it gas. when your timing is to retarded you back fire from the exhoust and it shouldn't sound like a diesel.
turn you desrabuter counter clockwise and see it shounds any better.

 

Let's fix the choke first.

1st, go here for reference http://www.carbs.net/Quads/E4MC.htm

With the choke thermostat housing off (which you obviously did from your 2nd picture), the tang on part # 348 should engage the hook on the thermostat element.

Hope that helps.

 

Thanks for that insight. Here is what's bugging me. Quote from myself:

"but the arm is actually all the way to the bottom "dot" or a little bit past it. I thought it was supposed to be at a 12'oclock setting"

I put the choke thermostat back in and turns it about an inch past the top dot on the housing, and the car now starts w/ no backfires, and idles around 700RPMS.. better than it was. I'll readjust the tang. Thanks guys

 

Don't freak if the choke housing isn't "straight up." Many choke elements are not when properly adjusted. Do all the advice, above from five7kid.

One thing to give you a "sane" starting point is to align the little rectangular "notch" in the metal backing plate (picture in second post) on the back of the choke element with the forward/top-most choke element retaining screw. That'll get you close.

Also..... that is not the original choke element that came with that carb. Trust me. It'll never line up so the element is "stright up." It came from a later model carb than you are using it on.

As long as the "loop" on the choke element is properly inserted AROUND "arm" inside the choke housing (not to one side or the other) and the choke element is actually heating up and pulling off like t should, this should get you PLENTY close for starters.

 

Ah, yeah. That's been triple checked. I turned the choke element counter-clockwise, and I'm not having that much of a problem with it any longer. It still idles a bit low, and once in an hour or so, when driving around 50, the RPM's will raise/lower for a few seconds. It seems I have most of the worries out of the way. I freak out when I'm working near gas. It's a thing I've always had.


I'll turn it a bit more to see if that helps correct the problem