4160 carb install and tune (for Mike)

Bingo! You called it on fingering the flapper. That's what the problem was. It stayed closed tight till it started to open. So I'll need to make an adjustment to keep it cracked open. Do I do that by bending the choke pull off rod, or is there another way?

I was racking my brain on how to seal the holes in the therm crossover, I almost cut the ends off the pipe, the bent them over, and welded them, but ended up just getting a pipe cap. I like your idea much better, I'm going to get some of those Welsh plugs.

I'll go with your recommendation on the intake. You haven't steered me wrong yet, and I thank you for sharing your knowledge.

Maybe you seen it, but I snuck a picture in of the plug that sits on top of the engine. It's kinda melted a little bit, and not to mention there are quite a bit of that type of plug around the engine bay. All look like they've seen better days. I'm big on preventive maintenance, and they look potentially problematic. Are they something to be concerned about? Should I cut them out and splice them back together, or leave them alone there probably fine?

You need to back off the cap.

Look at the way I set the choke.
It doesn't close all the way when cold.
Gary baselines at .125".... I start a little tighter at .110

And, yes you can adjust the vacuum pull-off too.

I'll go back and look.

I wouldn't be too concerned about that connector, but you should try to keep it off the exhaust manifold in the future.

Most of those connectors are available as pigtails from Motorcraft.
But just use the connector catalog (here on the forum somewhere) to get the numbers, then search eBay, Amazon, whatever...
They are tooo much $$$$ through Motorcraft direct.

ArdWrknTrk wrote

You need to back off the cap.

Look at the way I set the choke.
It doesn't close all the way when cold.
Gary baselines at .125".... I start a little tighter at .110

And, yes you can adjust the vacuum pull-off too.

I'll go back and look.

On my [Ford] Autolite 4100, the choke plate snaps completely closed with a bit of tension when it is very cold.  As soon as the engine fires, the choke plate immediately cracks open just a tiny bit to let a bit of air in.  As the engine builds up heat, that choke plate gradually opens until it has tension holding it completely open.

Rick - On carbs with a vacuum pulloff I set the choke to close fully and the pulloff to open it slightly, just like you said.  But the Edelbrocks that I've mainly used don't have the pulloff so I set the choke to not quite close.

Personally I like the idea of a pulloff as it is a feedback loop.  Set the choke a bit rich for starting and then if the pulloff brings it too far off the vacuum drops and the pulloff lets the choke close a bit.

Breaker breaker, anyone got a copy, I'm boots on the ground at the Cobra Headquarters.
Garagemahl we have a problem....ok ok enough with the funny business.
I initially came down to adjust my choke pull off and while doing that today I hooked up my tach and I can't seem to get the idle down below 850 RPM. At 850 RPM my vacuum pressure is around 18-20 in Hg, the timing is @10° with the vac advance hose un- plugged, and capped, and is not changed when plugged back in. My vacuum advance is running off the spark port of my carb as said to do in the Holley installation guide. I can't get an accurate timing until I can get the idle down s little lower right? Also the curb idle scree is pulled all the way back not touching, and I pulled the accelerator cable off the carb just to verify that nothing was being problematic.
What am I missing?

Sorry, but we've converted over to GMRS and away from CB.  

Seriously though, is your choke fully off?  If not, the fast idle cam will keep the idle off the curb idle screw.

But, if the choke is completely off, meaning standing up straight and the fast idle cam is out of the way, that would suggest you have a vacuum leak.  However, when you say the vacuum advance hose is off and plugged/capped, you mean so that air can't get to the carb, right?  There's no reason to worry about air getting to the vacuum advance on the distributor, but you don't want it going to the carb - although if the "spark port" is timed, meaning there's no vacuum at idle, it doesn't matter.

Choke plate is straight up, fast idle cam I'll double check I'm thinking it was clear.
Distributor vacuum advance was open to atmosphere,vthe hose that connects to it was plugged.
I'm thinking the spark port is timed because i put my vacuum guage on it initially for simplicity, and only got about 5 in Hgwhitch I thought was odd .
Could I have a defective distributor/ vac advance

Is it possible to have a vacuum leak in the brake booster to but still have normal braking? Alos if the accelerator pump is adjusted to heavily, would that cause a fast idle.
Fast idle cam confirmed clear
I sprayed around intake and the base of the carb with brake cleaner, and had no difference in engine RPM.

The need to disconnect and cap the vacuum line is only if it's hooked up like it should be -stock-

You don't have a 4180 and aren't using manifold vacuum, to a thermal vacuum switch, so none of this matters...

If you can't find a vacuum leak one of two things might cause your problem.

A) the secondaries might be cracked open. Either sticking on the EGR spacer or the stop screw (bottom side between the rear barrels) has them adjusted open.

B) you have an internal vacuum leak, where one of the runners is sucking from the valley.
You can usually see this as an oily plug

Ok thanks for the info, I'm going to call it a night here at Cobra Headquarters, and head home. I was able to get the idle down a little more by turning the fuel mixture screws inward, but upon doing that the engine loped with a range of approx 1000 RPM between ups and downs.  When you say "runners"are you taking about the valve guides?
One of the perks of having a van chasis is I've got access to the back of the motor is but geeze try looking down the carb. I do have a bore scope though may be able to check secondarys with it.

Don't use mixture to kill rpm's.
Adjust for highest vacuum or idle speed and use the throttle stop to adjust rpm's.

If the stop screw isn't touching and the butterfly is still cracked, disconnect the throttle cable.
Fix the cable attachment like I said in the first post.
If the cable doesn't let the throttle close, or won't open all the way with a brick on the pedal, then you need to address that.

Start at the beginning and do everything in order.
Like I said, you need to get A done before you start B.
You need to finish B before you start C.
.........

Hi Jim sorry for the delay in reply,  the Cobra is stretching her legs this holiday weekend. Were 100 miles from home, and she performing. I've got a little tinkering to do, but this is the best she's ever ran. Merging onto the freeway is effortless once the secondarys open up. After my first fuel stop i calculated 6.6 mpg, but there was three fairly large mountain passes we went over. Last time I took this route before I had done all the work I was lucky to get up to 35 mph on these passes, now I'm able to keep up with traffic, passing big rigs with a little pedal left.
Before leaving I was having idle issues. I did all the steps in order before asking and was able to get the idle back down. I believe the butterfly was sticking cracked open a tiny bit. The last couple days on start-up I've been having hard start, and idle issues. This time it was way to low today . Today it cranked longer than it should of to start on startup. I was looking around and discovered my choke was stuck open. Not quite sure why.  It closed immediately when I touched the fast idle cam.
I've still got to go through and adjust the fuel mixture for best vacuum, and figure why the choke is a little sticky. Hopefully I did right when I bent the choke linkage a little bit to adjust the pull off, and that's not why it's sticking.
Couple of questions, my Cruise control isn't working, and did before I took it all apart when replacing p/s pump, steering gear, water pump, and intake manifold. Is there a fuse? All vacuum lines are new and inplace.
Also in your response to my question you mentioned something about pulling vacuum from internally. Was that through the valve guides? Also wondering if running a dash pot nesessary? I've added a few images of what shape the intake manifold gasket was in before replacing, and was wanting to know if all the built up burnt oil that is stacked up on one side center is normal to see.

I suggested you must have an internal vacuum leak IF you've done everything externally and the throttle stop still could not idle the engine down.
I'm not sure why a new carburetor is sticking open, but you've found the problem yourself, so it seems none of the intake ports were pulling from the lifter valley.

It is not uncommon that exhaust carbon and cooked oil build up around the exhaust crossover, and even on the bottom of the intake manifold without the valley pan type gasket.
But if you read the instructions for any aluminum intake, they'll say not to use one.
Because the steel pan and aluminum intake expand and contract differently.

The one intake stud was definitely seeing coolant though!
That's why you use a little dab of RTV in the corners and I always add a light smear around the coolant passages in each corner.

The dashpot is just there to help smooth the return to idle.
Suddenly chopping the engine's air supply can lead to stalling under some conditions.
It is not a bad feature, but I'm not running one at this time.

Yes there is a fuse for the speed control.
Documentation>electrical>EVTM's>1985 EVTM>speed control>











Hope you're enjoying your New Years shakedown!
We'll have to work on that choke/starting issue when you get back.

Jim, I figured it out, my idle, and starting issue. Well actually a second set of eyes spotted it.
I was talking to my neighbor about the issues I was having with high idle, and rough start. While he was there I verified timing, idle was still to high. I told what you said could be causing it. Then while trying to back the idle off and actuating the throttle he noticed that the dash pot bracket wasn't allowing the throttle to close all the way. I hadn't been running a dash pot anyhow, so I removed the bracket, re- adjusted timing, and curb idle, backed the choke off a bit, and reset the fuel mixture off best vacuum, and wa'la.... She's s runner now. Gotta be carefully not to get a speeding ticket merging onto the freeway....and that's no BS...

Congratulations!    

It's interesting the bracket was holding the throttle open.
There must be some dimensional difference from when it was mounted on the 4180?

Anyway, glad your friend spotted it.
Much easier than chasing a non-existent vacuum leak.  

Congrat's!!!!  I love free fixes!