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What did you do for your ford today?

This thing is driving me crazy. I adjusted the kickdown, seems to be a bit early when it goes into action but shouldn't matter. Hit a sizable hill at 50 mph, and it's like it just had no more power to go, stabbed the throttle to make it downshift and it just bogged/popped/stumbled. Shifted it into 2nd and went for it and same thing. So that rules out the kickdown.

Carb's been rebuilt, has a brand new distributor with Pertronix III as of a couple of days ago, fuel filters are all clean and full of fuel, lines all look good. I've previously tested all of my plug wires.

It just feels like once it hits that window of load/speed (which isn't that heavy of a load or high of a speed) it just has no more "go" and starts popping.
 
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holdmypocket said:
This thing is driving me crazy. I adjusted the kickdown, seems to be a bit early when it goes into action but shouldn't matter. Hit a sizable hill at 50 mph, and it's like it just had no more power to go, stabbed the throttle to make it downshift and it just bogged/popped/stumbled. Shifted it into 2nd and went for it and same thing. So that rules out the kickdown.

Carb's been rebuilt, has a brand new distributor with Pertronix III as of a couple of days ago, fuel filters are all clean and full of fuel, lines all look good. I've previously tested all of my plug wires.

It just feels like once it hits that window of load/speed (which isn't that heavy of a load or high of a speed) it just has no more "go".
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So I don't want to go sort through all the threads, but let me see if I get this straight.

Are you working on the bog issue, or the kick down issue?

If you are saying it is all because it won't kick down. Can you take the cable off the carb and feed it into the cab in anyway to manuall check the operation?

Otherwise the bog issue depending on the carb could be the wrong/bad power valve or even the accelerator pump.
Can still be the distributor/timing issue but sounds like you ruled that out.
 
Tiha said:
So I don't want to go sort through all the threads, but let me see if I get this straight.

Are you working on the bog issue, or the kick down issue?

If you are saying it is all because it won't kick down. Can you take the cable off the carb and feed it into the cab in anyway to manuall check the operation?

Otherwise the bog issue depending on the carb could be the wrong/bad power valve or even the accelerator pump.
Can still be the distributor/timing issue but sounds like you ruled that out.
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Kickdown isn't the issue, I can manually shift into second, and I still get the same problem.

I've adjusted the accelerator pump in the past but can revisit. Have a bigger power valve I can try. Additionally, it feels like the secondaries aren't opening/getting enough fuel? but what do I know.
 
If you roll more slowly into WOT will it go or continue to stay lean?

Electric or manual choke?

I had a similar issue [edelbrock not holley] where the electric choke wasn't clearing the linkage enough and wouldn't let the secondaries open. Worse on hills due to gravity, even with vehicle fully warmed up. Rather than adjust e choke constantly, went to a manual
 
holdmypocket said:
Kickdown isn't the issue, I can manually shift into second, and I still get the same problem.

I've adjusted the accelerator pump in the past but can revisit. Have a bigger power valve I can try. Additionally, it feels like the secondaries aren't opening/getting enough fuel? but what do I know.
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Gotta say i hate holley. seems like every year it need an accelerator pump. Every year.

but that doesn't mean you have my luck.

I assume this is vacuum secondaries. You can add a screw to the secondary linkage to make them mechanical. But that may create other problems, like you will need a bigger squirter.
At least it will tell you if they are working, add a screw and go for a drive. See what is different.

Couldn't find a pic so I made one.

Put a machine screw, or sheet metal screw in where I have the blue dot and it will pull the secondaries open.

Maybe you have a vac diaphragm issue on the secondaries.
Idle-8-1600x1071.jpg
 
Provience said:
I had a similar issue [edelbrock not holley] where the electric choke wasn't clearing the linkage enough and wouldn't let the secondaries open. Worse on hills due to gravity, even with vehicle fully warmed up. Rather than adjust e choke constantly, went to a manual
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Bingo, another common issue. If he can't manually open them then they are inhibited. Most likely by the choke.
 
Provience said:
If you roll more slowly into WOT will it go or continue to stay lean?

Electric or manual choke?

I had a similar issue [edelbrock not holley] where the electric choke wasn't clearing the linkage enough and wouldn't let the secondaries open. Worse on hills due to gravity, even with vehicle fully warmed up. Rather than adjust e choke constantly, went to a manual
Click to expand...
Doesn't seem to matter if I roll into it or WOT.

I did just take a look at my choke and got a little familiar with the secondary linkage. It doesn't seem to be bound up or anything but I'm going to try the "paper clip" trick and see if the secondaries are opening up at all. I think i'll try the screw trick you described as well because it sounds like the secondaries not opening up/opening up enough could be the cause.

I had this carb on my heavier 78 F150 with 33's/c6/351m and never had this issue, but maybe the stock spring in the vacuum secondaries is too stiff for a little Bronco.
 
I think the screw thing made a difference but it didn't stay in place the entire drive. I'll have to find a screw and maybe a nut to keep it in place. Definitely felt like it had more power to start. Might just get the vacuum secondary spring kit and throw a lighter spring on it.
 
holdmypocket said:
I think the screw thing made a difference but it didn't stay in place the entire drive. I'll have to find a screw and maybe a nut to keep it in place. Definitely felt like it had more power to start. Might just get the vacuum secondary spring kit and throw a lighter spring on it.
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See if you can adjust the choke to max open as well, just in case the spring is getting weak
 
Been hosing down the trans with degreaser every night when I get home from work to hopefully break off the grime for when I drop the pan soon for the shift shaft seal change. In other news, tore into the carb. Never worked on an AFB style carb before, but I gotta say, the "full mechanical with no diaphragms" thing is kinda kick ass. Easy squeasy rebuild.
20240408_182331.jpg


Also Booger is really appreciating all these parts boxes showing up lately
20240406_142914(0).jpg
 
I hope I'm just a big dummy: when I started getting this Bronco together I was told the distributor already had a Pertronix Unit in it (I probably took a peek at it and didn't pay much attention), the coil was a Flamethrower I but it was leaking so I went ahead and replaced it with another.

When I started poking around the distributor recently I noticed it was an Ignitor III. I looked at a chart online and it seemed to me that the Ignitor III would work with the Flamethrower I. I got a new Ignitor III earlier this week (thinking the unit might be messed up) and if you've been following that hasn't solved my cruise speed stumble.

Long story short, I messaged Pertronix asking if a Ignitor III can work with a Flamethrower I coil and they said no, the resistance on the Flamethrower III coil is lower, and the voltage higher. Have one on the way, really hoping this fixes the problem. If not, it at least eliminates that. :homer:
 
holdmypocket said:
I hope I'm just a big dummy: when I started getting this Bronco together I was told the distributor already had a Pertronix Unit in it (I probably took a peek at it and didn't pay much attention), the coil was a Flamethrower I but it was leaking so I went ahead and replaced it with another.

When I started poking around the distributor recently I noticed it was an Ignitor III. I looked at a chart online and it seemed to me that the Ignitor III would work with the Flamethrower I. I got a new Ignitor III earlier this week (thinking the unit might be messed up) and if you've been following that hasn't solved my cruise speed stumble.

Long story short, I messaged Pertronix asking if a Ignitor III can work with a Flamethrower I coil and they said no, the resistance on the Flamethrower III coil is lower, and the voltage higher. Have one on the way, really hoping this fixes the problem. If not, it at least eliminates that. :homer:
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New Pertronix III module and III coil didn't fix it. Even did new plug wires. Will probably do new plugs because I have them.

Seems to run a bit better but still get that popping and stumble going up a hill hitting around 2200 rpm going 50-60. I removed the hose to the vac advanced and it didn't fix it either.

At this point I think this carb that I had rebuilt has some unknown issue and I'm leaning toward just replacing it with a new one but I hate the idea of throwing more money at this thing without knowing the root cause. This popping under light load or higher RPMs problem used to be avoidable by not getting too into the throttle or just downshifting. Now it seems like its progressed.
 
holdmypocket said:
New Pertronix III module and III coil didn't fix it. Even did new plug wires. Will probably do new plugs because I have them.

Seems to run a bit better but still get that popping and stumble going up a hill hitting around 2200 rpm going 50-60. I removed the hose to the vac advanced and it didn't fix it either.

At this point I think this carb that I had rebuilt has some unknown issue and I'm leaning toward just replacing it with a new one but I hate the idea of throwing more money at this thing without knowing the root cause. This popping under light load or higher RPMs problem used to be avoidable by not getting too into the throttle or just downshifting. Now it seems like its progressed.
Click to expand...
Shouldn't cost no money to pop it open and spray out the venturies etc. And such

Did you do the bolt/lockout secondaries dealio for testing after the ignition changes?
 
Did some PM work on the '73 Bronco. Changed front and rear gear oil and added a Yukon front diff cover. Flushed the power steering system and put in fresh fluid. Then had to fix the wiring for the lights on the headache rack of the F-350 that my fuck face dog chewed up yesterday.


Little more bling for the EB:
IMG_0308.jpeg
 
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