Rochester carb choke assembly

[Tvix]

Hi all,

Working on rebuilding the carb and adding an electric choke. Problem is the picture I took and the paper instructions do not show this rod and plate go. Can’t find a video or anything clear online.

Can someone tell me how to re assemble this choke so I can install the electric?

Thanks!

[geezer#99]

Well you know that rod and plate aren’t for the choke!
They’re the accelerator pump arm and rod.

[Astro-Balls]

https://www.chevyhardcore.com/tech-s...ication-guide/

[Tvix]

Originally Posted by geezer#99

Well you know that rod and plate aren’t for the choke!
They’re the accelerator pump arm and rod.

Face palm moment... thanks!

[HO455]

Welcome Aboard neighbor. You may not need any additional advice but if your interested (I don't even know what style of electric choke you are using) here is a link to my installation. Scroll down to post 590 and there is more on the next page (post 618) about setting the choke up.
Good luck and stay healthy.

https://67-72chevytrucks.com/vboard/...98377&page=24o

[Tvix]

Originally Posted by HO455

Welcome Aboard neighbor. You may not need any additional advice but if your interested (I don't even know what style of electric choke you are using) here is a link to my installation. Scroll down to post 590 and there is more on the next page (post 618) about setting the choke up.
Good luck and stay healthy.

https://67-72chevytrucks.com/vboard/...98377&page=24o

Hey thanks for the link it helped! I’m about done just need a 12v source to tap into. Any idea what would be best?

[LockDoc]

Originally Posted by Tvix

Hey thanks for the link it helped! I’m about done just need a 12v source to tap into. Any idea what would be best?

I used the "IGN UNFUSED" terminal on the fuse block. If you wanted a fuse in the circuit you could add an in line fuse.

LockDoc

[randy500]

If you want the choke to work good, run the power wire through an oil pressure switch so it's only heating up when the engine is running. Otherwise it starts heating before its started and if it dies continues to heat.

[HO455]

Originally Posted by Tvix

Hey thanks for the link it helped! I’m about done just need a 12v source to tap into. Any idea what would be best?

Glad it was helpful. On mine I used the 12 volt power feed to the T400 kick down. But most trucks don't have that. Doing like LockDoc says would be good.

[Tvix]

Block sounds like a good choice. I drove the truck and it ran pretty good. I plan on wiring the choke tomorrow along with trying to fine tune it and see what happens.

[Tvix]

I’m not getting a high idle at start up. Turning the choke screw isn’t affecting the idle.

This should be touching the high idle cam correct? It’s not really touching, can’t figure out why..

[HO455]

From the photo you posted I am unable to see the fast idle cam. It maybe hidden from view if so it may be upside down. (Easy to do trust me.) See photo for the correct location/orientation of the cam with the choke closed and open. Last picture is one version of cam. There are at least a dozen varieties of them.

[Tvix]

Yes cam is there just hanging lower. This pic was the only I had and the carb was still half apart.

It seems like my cam follower isn’t touching the fast idle cam.. I’ll mess with it some more today and see what the deal is.

[HO455]

The adjustment screw will not touch the cam when it is in the lower position. (2nd photo) Forgive me if you are already aware of that.

[Tvix]

Not the screw, the follower that touches the cam is not touching into the step. The black and white instruction you posted. (I have the same)

[Tvix]

I’m getting closer.

Choke engaged the truck fired right up idling 1500ish. After letting warm up a little I tapped the gas (old intake choke back on for now) and it went down closer to regular idle. Issue now is if I hit the gas 3rd time it brings the choke back to the middle (2nd step?) position and a higher idle around 1000-1100ish

See pictures; first picture is in regular idle choke plate fully open(pushed with finger to get it all the way down) Second picture is after I hit the gas it brings choke back on. Why is me hitting the gas bringing the choke up to what I believe is the 2nd step?

[randy500]

The choke assembly when not fully warmed up brings the cam up.
Just because the instructions say so much rpm on the high step doesn't mean you cant refine the adjustment. That adjustment and setting is just a starting point.
Your probably on the 2 step more often and for longer periods of time, just adjust the idle down using the same screw while on step 2 of the cam.

[HO455]

In the second picture the choke stove (new electric unit) is not fully warmed up and so it will cause the choke to be half on. When cold it pulls the choke shut and as the temperature comes up it moves the choke slowly open. It may take 3-5 minutes to get fully opened depending on ambient temperature and the temperature of the engine. If the choke is taking too long to come open then rotating the choke stove (new electric unit) to a leaner position will shorten the time the choke is on. However go to far and the choke may not close completely thus necessitating adjustment of the linkages. Another way to get it to open quicker is to move the sensor (if you have that style) closer to the exhaust crossover in the intake manifold.

[Tvix]

Originally Posted by randy500

The choke assembly when not fully warmed up brings the cam up.
Just because the instructions say so much rpm on the high step doesn't mean you cant refine the adjustment. That adjustment and setting is just a starting point.
Your probably on the 2 step more often and for longer periods of time, just adjust the idle down using the same screw while on step 2 of the cam.

Thanks for this! Dialed it down and took it for a spin. Came back and choke plate fully open! I think she’s good to go

[Tvix]

Originally Posted by HO455

In the second picture the choke stove (new electric unit) is not fully warmed up and so it will cause the choke to be half on. When cold it pulls the choke shut and as the temperature comes up it moves the choke slowly open. It may take 3-5 minutes to get fully opened depending on ambient temperature and the temperature of the engine. If the choke is taking too long to come open then rotating the choke stove (new electric unit) to a leaner position will shorten the time the choke is on. However go to far and the choke may not close completely thus necessitating adjustment of the linkages. Another way to get it to open quicker is to move the sensor (if you have that style) closer to the exhaust crossover in the intake manifold.

Thanks for the ongoing help man, much appreciated!

[HO455]

You're welcome. Glad to hear you have it working.

[demian5]

I have seen people mistakenly connect to thew coil on a external coil ignition and wonder why the choke didn't work right. Reason being that the factory coil wire is only about 6 volts. Make sure its hooked up to an ignition fused wire that gets a full 12 volts like LockDoc says.