Help with my electric choke.

[yetiwarrior82]

ok i have a 1979 CJ7 and its a AMC 258 i6 / 4.2l inline 6 and i need help with my choke. its an electric choke but one wire (red) doesn't go anywhere. the green one is plugged in. if anyone can help me find out where to plug the red into or wire it to so my choke will work and it will actually idle right lol

 

[jasonmark1993]

One should be key on power or engine running power and the other is ground.

The choke is just a bi metal coil that winds up/unwinds as it heats and cools.

Engine running power is better simply because if you leave the key on without the engine running, the coil will heat up, unwind, and you have less choke. Key on power really is ok though.

A good way to set the choke is to have the air cleaner off when you go to start it--this is done cold first thing in am. Have the screws loose so you can adjust it. You'll need to "set" the choke by depressing the throttle. You'll be able to see the choke plate move as you move the black plastic case around. Usually a little less than full choke is good. Go ahead and start the engine and you'll be able to see the choke plate opening as it warms up. If you need more or less choke, just make the proper adjustments.

From looking at the picture, it looks like you have full choke--Im guessing the engine is cold. So without it hooked up, the engine heat is warming the choke coil allowing it to open. The choke will open much quicker with voltage to it. If the engine starts and idles nice cold, I wouldn't adjust anything. Just get the power or ground hooked up.

 

[yetiwarrior82]

i that that was a hot air choke. but anyways if what you are saying is true why does my jeep idle so poorly. like it will idle bad and then either just stall or back fire through the carb and die. i have a feeling i can figure it out i'm just looking for input. and can you maybe help me out with the fact that my gauges don't work either lol i know its off topic but just wondering. i could really use the fuel gauge and temp gauge lol

 

[jasonmark1993]

Does it idle bad when you first start it or after it warms up?

Personally Id just wire the sucker open unless you live in a cold area. If you still have the problem, its not the choke.

As for the temp and fuel, Id take a look at the grounds on the back of the gauges. On my 73 they share a ground and it was a crappy one. Chances are that both gauges or senders aren't bad so check that and make sure they have key on power.

You can test the entire circuit easily by turning the key on and grounding the wire at the temp sender or fuel level sender. That should peg the gauges. You'll want to remove the wire from the sending unit and ground it.

 

[yetiwarrior82]

it idles bad when i first start it. does like to stay running and then after a little it will stay running but still idle bad. i think it needs adjustment. and i'll try that with the gauges tomorrow. thanks helped a lot.

 

[IOPort51]

The electric choke is "helped" by a switch next to the oil pressure sending unit that closes when the oil temp is at operating temp.
the electric part is not absolutely needed as the choke will open as the manifold warms up. Is the vacuum diaphragm in the picture hooked up to the choke and a manifold vacuum source? That is a carter one barrel is it not?? Is it clean and have you adjusted the idle jets?? Have you checked for vacuum leaks?

 

[mtnwhlr]

One should be key on power or engine running power and the other is ground.

The choke is just a bi metal coil that winds up/unwinds as it heats and cools.

Engine running power is better simply because if you leave the key on without the engine running, the coil will heat up, unwind, and you have less choke. Key on power really is ok though.

A good way to set the choke is to have the air cleaner off when you go to start it--this is done cold first thing in am. Have the screws loose so you can adjust it. You'll need to "set" the choke by depressing the throttle. You'll be able to see the choke plate move as you move the black plastic case around. Usually a little less than full choke is good. Go ahead and start the engine and you'll be able to see the choke plate opening as it warms up. If you need more or less choke, just make the proper adjustments.

From looking at the picture, it looks like you have full choke--Im guessing the engine is cold. So without it hooked up, the engine heat is warming the choke coil allowing it to open. The choke will open much quicker with voltage to it. If the engine starts and idles nice cold, I wouldn't adjust anything. Just get the power or ground hooked up.

This is best advise that has been giving. You should have 12 volt to the choke that is what opens it as the motor warms and keeps it open when it running.

 

[IOPort51]

If you have a Haynes service manual chapter 10 page 22 , upper right hand corner grid A-6 electric choke is controlled by the oil pressure switch. This should not be confused with the oil pressure sending unit as seen in grid C-4. These will both be located on the passenger side close to the rear of the motor.

 

[PaRenegade]

If you have a Haynes service manual chapter 10 page 22 , upper right hand corner grid A-6 electric choke is controlled by the oil pressure switch.

Interesting. I'll have to look at my manual tonight.
The picture doesn't show it but by chance does it have a sol-vac mounted on the left front corner? Mine does but it's an 82, but that is where the extra wire from my electric choke goes.

 

[jasonmark1993]

The reference to the oil pressure switch is so you have ENGINE RUNNING POWER as I described before. If you have that and can wire it that way, great.

If not, key on power will work. Its not common for you to sit around with the key on before starting the vehicle. Using the oil pressure switched power source just prevents the choke from opening early if the engine wasn't running.

First thing I would do is wire the choke open to eliminate that as a problem. If the engine doesn't run properly when warm with it wired open, I wouldn't spend any time fixing the choke. I would address the warm idle problem first THEN work on the choke/cold start issue.