I might be off topic here and if there is another board that has the answer I wouldn't mind a link, but on to my question. I have a stock Holley 4180 with an electric choke. Unfortunately I can't get the vacuum break to work. When I start the truck I have to hold the butterfly open a bit to keep it idling normally. What adjustment (if any) do I have to do. Where should the vacuum line go from the front left (as your looking at the front) of the carb? I was told that it should go to the vacuum advance on the distributor but that may not be correct. Thanks guys and, like I said, if there is a post that has this answer already I would not mind being pointed in the right direction.

 

I'm not sure if you asked two questions, one about the vacuum break and one about the vacuum advance to the distributor, or just one about the vacuum break and where its vacuum should come from. But, I'll assume two.

According to the Chilton's manual I have the vacuum break (choke pull-down in Fordspeak) is internally connected, meaning that there is no external vacuum line like there is with most carbs. And, that fits with the 4180 I have here beside me.

The distributor is supposed to go to ported vacuum, although many people do run it to full-time vacuum. I don't know which port is which, but if your vacuum routing diagram is still usable you should be able to tell from that. However, it is really pretty simple - start the truck and pull the cap to a vacuum port and see if it has vacuum at idle. If not, the vacuum advance can go to that one.

As for adjustments, the Chilton's again comes to the rescue and says all 4180's are to be set at .200 to .220" pull-down. Here's the process:

1. Remove the air cleaner and the carb
2. Put the carb on a stand that allows access to the pull-down vacuum passage on the underside of the throttle body. (There's no picture of which one that is, btw.)
3. Mark the choke cap position relative to the housing and remove the cap, gasket, and retainer
4. Reinstall the cap, including the gasket, and rotate it 90 degrees counter clockwise from the original setting and secure with a screw
5. With the choke fully closed actuate the pull-down using an outside vacuum source of at least 17" of Hg
6. Use a drill bit to gauge the opening
7. If the dimensions is out of spec, carefully remove the diaphragm adjustment screw cap with a small punch or screw driver
8. Turn the adjusting screw w/a 5/8" allen wrench clockwise to decrease the setting or counter-clockwise to increase it
9. Apply RTV to the adjustment screw cavity
10. Put it all back together

If yours isn't pulling the choke open at all it is possible the diaphragm is split. You can find that out by pulling the cover w/o removing the carb. It is the diaphragm just in front of the choke housing and the cover is held on with 4 screws.

 

Thanks Gary I'll try what I can when I get home. I believe that my carb is odd. The choke on it is non-adjustable. I did put on a phenolic spacer and I wonder if that is the problem. I'll keep working on it. Thanks again.

 

I see what you mean about the choke being non-adjustable, but beg to differ - it is just not "easily adjusted". They haven't made many things that I haven't figured out how to adjust.

Mine has a tag that reads E5TE ZA A 5B6. And it looks like it would take drilling the two rivets out and then tapping them for a screw. Not easy but not all that difficult. But, I think I'm even happier that I'm going back w/an Edelbrock/Carter carb 'cause this thing is meant to frustrate on several levels.

 

I know what you mean. Even adjusting the idle mixture screws is a pain. I did grind slots in the rivets so I could get a slotted screwdriver in there to unscrew them. At least on mine they were screws meant to look like rivets.

 

I got my carb-to-air cleaner gasket. Felpro 5198, it fits the Carter YFA (below).

I checked the choke on my truck (1986). With a cold engine (morning after a ~50 degree F night), after pressing gas pedal to the floor once and releasing it (engine off), here's what my choke plate looks like. It is completely closed.



Then I started the truck. With the engine cold but running, the choke "vacuum unloader" aka "pulldown motor" uses engine vacuum to open the choke plate a bit. On the upper right side of the carb you can see that the shaft of the choke pulldown motor is retracted by vacuum and this opens the choke plate a small amount. Thanks for the info Gary, it works just like you explained.

 

Welcome. Glad to help. Btw, that's one of the cleanest carbs I've seen. Do you really drive the truck?

 

Never! It might get dirty if I drove it. I just go out every few days and clean it inside and out with a toothbrush

 

I have a carb-related question that I might as well ask here, it doesn't seem to merit its own thread:

Attached to the rear of my carb is a "military dog-tag" style chain. You can see part of it in the picture above (upper right).

Is that strange chain a stock application? What is its purpose?

 

Does the tag start with something like E5 or E6? That sounds like the tag that should be under one of the screws but instead has been attached via a bead chain. If so, the tag gives the #'s on the carb you need to get the right kit and spec's, or to replace it.

 

No, sorry, I wasn't clear - there is no tag on the bead chain, it is just the bead chain itself I was asking about. I just thought it was odd to have a bead chain as part of the carb linkage, and was wondering if this bead chain was an actual Ford part, or just something the PO or a mechanic used simply because he had one laying about. And if it is a stock part, what does it do?

 

The only use of a beaded chain that I'm aware of is in the cruise control linkage. Do you have cruise? Is the chain connected to the throttle linkage?

 

Yes I have cruise control - that must be what it is for. Interesting. I've never used the cruise control, its kind of strange to have cruise control on a manual transmission like mine.

 

The chain is so the cruise unit can pull on the throttle but you can give it more throttle with the pedal without the linkage binding. The chain just goes slack.

 

That makes perfect sense. Thanks Gary!