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Just a couple of added details. You've had some great advice so far, so sorry if they were already mentioned. Just mentioning that the hole in the cover for the accelerator pump is not to be plugged. It's there to allow the sealed diaphragm to move easily both ways without creating a vacuum on the one side.
It's double purpose I suppose is that it acts as a weep hole and lets you know when your diaphragm is toast.
The gap in the first picture that was showing your dashpot/solenoid/thingy, is only supposed to be there under two conditions. When the key is off and when the choke is at least partially closed and you're running on the high-idle circuit.
Yours appears to not be connected though, so it's never going to be properly utilized to set the curb idle. The choke is also a little bit closed in the pictures, so it's possible the linkage is keeping the throttle lever from going down to full low idle.
Normally when you turn the key the pin pops out and pushes the throttle lever to your chosen low idle (about 700 rpm let's say) and when you shut the engine off, that pin retracts and your carb closes down to a base idle approximately 200-300 rpm lower. Thus acting as an anti-dieseling solenoid (which is what it's called in some books too) for clean shut-offs.
The fitting on the top of the carb is the bowl vent (float bowl) and is normally connected to the charcoal canister part of the evaporative emissions system by a rubber hose.
If all of your evap system is gone you should plug it up as the others stated. Dust and water and debris can otherwise get into the carburetor directly any time it's open. The bent lever arm thingy attached to that little piston above the accelerator pump opens the vent to let fumes go into the system and either get captured by the charcoal or sucked back into the engine to be burned.
Capping it off also keeps the fumes down in case it's parked in the garage. Keeps the air cleaner too.
Yep, it plugs somewhere but not on your carb..... 8mm silicone...... sounds like it has something to do with ignition..... where does the other end go?
(You still need to put in a kit.......LOL)...... said the pest.
Best way to learn is by doing.... I think you have already learned a lot about your carb.
The throttle kicker solenoid connects to power wire on firewall, just below hood seal. Only gets power when key is "on". The way these engines are tuned, they might be necessary to prevent dieseling when shut off.
Nipple on top is carb bowl vent. Gasoline is volatile and likes to vaporize. Smells good, but bad to breath and not great for the environment. That should have a hose going to the charcoal canister near passenger fender.
Go ahead get the Chinese carb and let us know how they work. A lot of people say they're bad. Poor metallurgy and loose tolerances... Whatever you do, please consider not throwing away the original carburetor, these things don't grow on trees anymore!
Had pretty good reviews at least. I never throw anything away, my fiancée loves that. :-) Mike,
I wonder if that dashpot is from the original engine the truck had, which was the 4.9 6 cylinder
Good news everyone! I got those vacuum caps and stuck one on that line and now my gas pedal doesn’t stick as much! Yee
Capping the bowl vent did not help your sticking linkage. Something else did.
Perhaps it's just the amount of movement you've been putting the linkage through during testing. Perhaps something else joggled loose after taking the air cleaner off.
Or perhaps it's going to stick again because of the awkward angle of the cable that the bracket puts it in.
I would not only lubricate it at least a little in the exposed area under the spring, but also straighten the bracket and cable. Do you have a picture of how the cable is routed?
You might find that it's easy to bend the support bracket towards the driver's side, but then it might put the cable at more of an angle. It looks right now like it's routed around a vacuum line (perhaps for the brake booster) and frankly, over the years the angle of a strong cable could have actually forced the bracket to bend a little each year.
You could also slightly move the throttle lever's top section towards the carburetor at the same time. Which would lessen the amount of change needed for each end. But I would be careful about putting force on it. If you're getting a new/rebuilt carb rather than a rebuild kit though, this might not be necessary.
Originally Posted by Jack118711
Does this plug somewhere?:/
When I clicked reply none of the other posts had showed up for some reason (I'm in universal scroll mode, so should see it all in one screen) but I see now that you've had the answer.
Ford (and the other OEM's too I believe) used both electric solenoid and vacuum dash pot style actuators. Not sure what got which and when or why, but they were both legit. Mine is electric like yours, but other trucks I've had used the vacuum like Mike's.
Your idle quality does not depend on that part. Only the anti-dieseling properties. Or in some cases, they're utilized to kick up the idle a notch when things like A/C are engaged, or the engine temperatures reach a certain level. Higher idle might help cool an engine that is idling for extended periods. Just like changing ignition timing.
And as said, a single keyed wire actuates it and would normally have a matching connector half that obviously fits into the other half you have.
The throttle cable does seem installed wrong. When the truck is off, the pedal moves fine but sticks once the truck is on. It seemed like too much air was in the carb, vacuuming it shut. So covering that air hose seem to make it better I thought
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