Choke??

[Kidd-7]

When I start my truck I have to hold the gas in some and once she starts hold it in for a little while before she'll idle good. I'm thinking the choke isn't working. Anyway to verify this? Anything else I should look at? Last time I played with it the piston moved freely. Thanks.

[dmack91]

With the engine cold, remove the air filter. The choke should still be open from the last time you drove it.

Now, pump the gas pedal or work the throttle linkage by hand. As soon as you move it to open, the choke plate should close. If not, something is not allowing it to work properly.

[68gmsee]

Assuming you have an automatic choke check to make sure it's hooked up first. A lot of these old trucks had an engine heated coil that would rust or the cover would fall off and people would just not use it or install a manual choke. If it's been converted to an electric make sure you're getting 12 volts to it and that it's adjusted properly as damck91 mentioned.


The way I adjust mine:

With engine cold and choke activated (closed) I adjust it until starts to open and then slowly adjust the other way until it closes again. You can play with it back and forth depending on your weather.

[Kidd-7]

Attached are pics of what I have; there are 3 wires, where would I see the 12v at? Also, what about the vac lines?

[Kidd-7]

Also, here is a pic of the carb, engine cold.

[lil hoodlum]

I might be wrong on this, on the first picture you posted, the yahoo thing with three wires to it is your idle stop solenoid. I'm not sure if that has anything to do with the choke.

Keith

[lil hoodlum]

The circle thing on the upper left hand side is the choke pull off assembly.

I think?!?!

Good luck,

Keith

[Kidd-7]

The more I was looking at it; the more I thought along your lines. What does the Idle stop do?

[lil hoodlum]

I believe the idle stop solenoid is supposed to raise the curb idle speed to compensate for an additional load such as an air conditioner.

Good luck!

Keith

[lil hoodlum]

Your choke pull off assembly should be activated by vacuum. It should have a rubber hose on the other end that connects to a port on the back side of the carburetor. If you have a vacuum pump, I would hook it up to the hose off of the end of the choke pull off assembly to see if it is moving the plunger.

I would suspect though that maybe the vaccuum hose is just old and may have some cracking it. It might be worth it to start replacing some of those old vaccuum lines.

I have rebuilt several of these old 2 barrel rochester but I never did rebuilt one like the one that you have.

Good luck,

Keith

[Shyguy]

If I remember right the idle solenoid is part of the smog setup on newer carbs and when the engine is turned off it shuts off the flapper in the carb. Most carbs I see running on these old trucks do not have that solenoid.

[Kidd-7]

Originally Posted by Shyguy

If I remember right the idle solenoid is part of the smog setup on newer carbs and when the engine is turned off it shuts off the flapper in the carb. Most carbs I see running on these old trucks do not have that solenoid.

I don't think mine works anyway, is there anything special to remove it? Do you know what to do with the wires & hoses?

[Kidd-7]

Keith, thanks for the input. I played around with it some, when I move the throttle linkage the "butterflies" up top don't close, I have to physically close them and they are tight. They do not close all the way either, but I don't see how to adjust them. Is there something I can use to lub the joints? I will check on the vacuum hoses, they probably do need replaced.

[Kidd-7]

Got it fixed; she started good and ran great. Attached is what I found. The carb was pretty gummed up, so I cleaned off all the pivot points and the flaps moved well, but still didn't shut. So, I pulled the spring and found that crud in there, clean it out and tightened it up. Beautiful.

[stsalvage]

if your looking for the Manuel pull choke i have them for 1967--72 chevy trucks

[kcsa75]

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