I'm working on a 67' F100 Inline 6 (maybe a 300? I cant tell) that my buddy owns and someone has done some really questionable connections the the carburetor. Its been "restored" and I don't know if its the original engine. I tried to drive it and it falls flat on its face whenever you step on the gas pedal. They connected manifold vacuum to the distributor, not ported, and I also don't believe the accelerator pump is working.

Anyways I'm having trouble identifying it so I can buy a rebuild kit for, but also for identifying appropriate vaccuum ports. Hopefully from the pictures I have someone can help identify it.
There are two sets of numbers on the back of the carb: 7860 and just below that is 0120
I couldnt see any other markings.
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Hello don3194, welcome to FTZ, Need to see a picture of the distributor (Dizzy). The stock Dizzy and Carburetor (Carb) on the 240/300 engine need to be matched. Meaning you can't just put any carb up against the original Dizzy. The original Dizzy only has vacuum advance, for advancing the spark only and it needs a Carb that controls the advance by both manifold and ported vacuum, depending on the load placed on the engine and how much gas pedal your giving it. It is Fords, Load O Matic Ignition. The picture I see of the Carb says it's not of the Original Type.

If your friend has installed a aftermarket performance Dizzy or upgraded to a Ford Dura Spark II Dizzy, then we need to look into what is happening with your problem.

Also looks like that Carb was auto choke and been converted to manual.
Cap

 

Alright I dont have the best picture but hopefully it will do. The distributor advance was connected to the port just off the automatic choke, which has vacuum at it. It would immediately pull the advance in when you started it. Unfortunately I have discovered that 4 of his other classic trucks and one car had the advance not connected to ported vacuum. Also keep in mind he knows absolutely nothing about working on cars, he just hires others to work on them(some of them have apparently also been clueless).
I take it you can't quite tell what this carb is from?
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So it is definitely not an original Dizzy. ??? Maybe Ford Duraspark II? A pic of the coil would be good. Is there a pot metal box on the fender well that the Dizzy wires go to and where the wires enter the pot, is the grommet Blue? Remove the cap and grab the rotor and lightly twist CW or CCW, let go and it should spring back to where you found it. A pic with cap off would be good.
A couple back to basics. Remove the vacuum line at the Dizzy and plug it. Base timing check if you can with engine at low idle. Is truck Std or Auto transmission?? Set timing per book for now for either Std or Auto. 240 / 300 engines have timing gears, so no worry about worn sloppy timing chain/gears. Test Centrifugal advance by slowly increasing RPMs and watch the timing marks, should show a smooth advance and return back at idle to base setting, vacuum line still disconnected and plugged. IF you have a vacuum gauge or your finger will do. Find one of the lowest ports on the Carb that has NO vacuum at idle and when you slightly advance the RPMs vacuum begins to occur. That is a ported vacuum source and preferred at this time to go to the advance chamber on the Dizzy. Hook the hose up at each end and test the vacuum advance, a quick, crack of the throttle should show a quick snap advance of the timing marks compared to the smooth of the centrifugal.
If all this is good and you still have this Flat/ Dead response to accelerating.......then need to consider the Carb.
Cap

 

Alright, I 'll check into the timing tomorrow. It did have a module on the fender with wires running to the distributor, my dad pointed out that he remembered it on his 75' Ford Mustang, I think thats what he said. I expect the initial timing to be way off considering the distributor was 100% connected to manifold vacuum. Again I will check everything you said tomorrow, but I would like to get a rebuild kit for the carb since it does have a minor leak on it.
It is mated to an Auto transmission, no idea what it is.

 

Remember as I said, base timing is ALWAYS (capitals not shouting, just important) checked with vacuum line disconnected and plugged. Engine at warmed up low/curb idle. Timing MAY be correct as previous person might have known proper procedure. You should find all specs on line and choose for Auto transmission. Get All info at same time, timing, curb idle which final adjustment of will be with truck in Drive. Picture of Box on fender well, showing the grommet.

 

The timing was set to around 5 degrees initial. I set it to 10 degrees at idle with the vacuum disconnected. Seemed to run well that way. The centrifugal/mechanical advance works just find. I got a picture of the inside of the distributor.
I also checked all the ports I could find on the carburetor and I couldn't find an appropriate port vacuum, in my opinion. In the picture the bottom two ports are directly to the manifold which I checked to be manifold vacuum. The middle port on the carburetor reads at 10 inHg all the time except when at idle. The port off the choke gives 10 inHg at idle and idle only. And the top most port doesnt have vacuum.

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Yes on Dura Spark II ignition. Still want to know the color of the grommet where wires go into the box on the fender well.

OK on your timing checks, with ONE question because we don't know if P O may have tricked the Dizzy to some extent. On checking the centrifugal/mechanical advance. You should look to see if there is NO advance for a small amount of RPM increase. It is possible the advance may have started at the idle RPM you have now and is not fully retracted as it should to properly set the base timing.

The two ports on manifold look good. One to the PCV valve ( and is there a PCV valve in the valve cover under the braided hose and red nut with a good connection hose to valve and valve into valve cover grommet ??) The other to the Brake Booster. The one on the top of Carb (air horn) is just a filtered fresh air source to possibly the inside of a heat tube that would feed an automatic choke, Non electric.

On to a ported source for the vacuum advance. What is the RPM's at Idle?? If Not specified curb idle, the throttle plate may be open enough to be creating the vacuum draw you are finding now. The 2 with 10 inches vacuum, the one that has no vacuum at idle is probably the ported one you want. All just mentioned above in this post squared away first. DO A TEST, vac gauge hooked to this port, start engine, begin increasing RPM's, watch the gauge, slowly go up to at least 2000 RPM's, the gauge should increase vacuum above the 10 inches you mention and hold. Return back down to idle speed. IF Yes, that is the one for vacuum advance. A final test, snap the throttle open quickly and back to idle a couple of times, the gauge should jump up rapidly and down as you go back to idle. I know a lot of writing, but really not a lot to do. NEED to be sure thing are right.

Is there a vacuum hose going down to the transmission??
Cap

 

Forgive me I forgot to write in that the grommet is infact blue. There appears to be no advance for a small amount of RPM increase. The mechanical advance seems to move freely and retract as I would expect.
There is a PCV valve attached to that hose.
I am not 100% sure on the idle RPM, by my ear I would guess it to be around 600-700 RPMs.
I did test the port that gives me 10 inHg off idle and it seemed to only give a maximum of 10 and thats it. I dont have a tachometer but when I go back to work on it Thursday I will test the Vacuum making sure to hold it at around 2000 RPM. Just to see what would happen I connected the distributor vacuum advance to the port with 10 inHg and it doesn't pull in the diaphragm nor does pull in the linkage coming out of it. It seems as if there isn't enough of a vacuum signal from that port. I did test again to make sure the diaphragm does work and it still does.

There is a hose going down to the transmission, they had it connected to the port off the original choke and so I corrected that to be on the full manifold vacuum.

 

OK on Blue Grommet, control box you want and most common.
OK on No advance on slight RPM increase, meaning, yes advance completely retracted to set base timing.
OK on PCV valve
OK on no tachometer, FYI, because I mess with single cylinder lawn mower engines up to automotive engines with points and electronic ignitions, I use a hand held photo cell tach. A piece of reflective tape on what is revolving, aim the tach's, I guess, infrared beam for a reading. They're all over the internet, some quite reasonable. There are timing lights with built in tachometers, do you have a Gear Head Friend who might have one to borrow?
OK on hose to transmission, yes manifold vacuum, it has to do with proper shifting and possibly down shifting when you want to hit passing gear. The vacuum at auto choke where it was connected, plug it. It would have pulled the clean heated air from the exhaust manifold stove.

ON the ported vacuum search, it is going to be a port in the lower body of the carb, down at the throttle plate. Basically, when at idle there almost no air passing the throttle plate, as the the plate begins to open, air rushing thru creates a vacuum at a small hole/orifice in the wall of the body and that hole goes to the port you want. ON Your Test of the port with no vacuum at idle, does the vacuum go from NONE to 10, smoothly as you slowly open the throttle. It should, that's why I asked you to do the snap test. If you snap the throttle open the gauge should jump VERY quickly, open throttle slowly and gauge should show and hold vacuum at any point you stop opening the throttle. Trying to use best words I can on this. You said there is a second port that holds 10 inches vacuum all the time?? have or can you check it out?? by testing for response??

I don't recognize this carb. Probably from a later 300 six with various pollution controls. I'll look around and see if I can identify.
Cap

 

Your Carb looks like this 1965-1969 , "240-300 Service Replacement, Holley 1940" , that's the description

https://nationalcarburetors.com/ford-trucks_c_292.html_6-cylinder-1-barrel-carburetor_1968

 

OK, so the puzzle gets deeper. This Holley 1940, which I'm not familiar with is said to be a service replacement, and in my estimation, designed to be used with Ford's, Load O Matic Dizzy, seeing as the designated years are 1965-1969, the era the Load O Matic was used on the 240-300. This carb is not going to operate the vacuum chamber on the Dura Spark II Dizzy.

SO..... here's the route I would take. Load O Matic, HAS TO HAVE VACUUM Advance because it is the ONLY means of advancing the spark. On Engines that have mechanical / centrifugal advance, you Do Not Need vacuum advance at all for good performance. Ever see a Racecar Engine with vacuum advance. The Vacuum advance is designed to help with BETTER FUEL MILEAGE, this tidbit taught, 40 plus years ago, at a seminar on engine performance by Echlin Ignition Products.

Just plug or cap off the port on the carb that went to the dizzy in your first 3 pictures, the rubber hose that went over the valve cover to the Dizzy.
Base timing set for Auto transmission spec, take the truck for a ride, just drive normal, no pedal to the metal acceleration. Run OK?? Still have bog or hesitation??
You mentioned questioning the accelerating pump may not be working, and a fuel leak. There are #'s on that carb to identify it and get the correct rebuild kit. Holley use a 4 digit number called a List Number. In your first post, 7860 may be it. Cap

 

Thanks for your help identifying the carburetor. The truck actually did start to run quite a bit better after fixing the way the vacuum advance was connected and resetting the timing. It seemed to drive ok, but it was all warmed up, I'll see about how it is when its not fully heat soaked. I did discover the accelerator pump is working but I will see if I can find a rebuilt kit now. Thanks again.

 

Also based on those pictures of the carburetor on the website you posted, it appears I missed one vacuum port next to the idle air/fuel mixture screw. I didnt know it was there.

 

A, HA do test that port for the ported one you have been looking for. This Carb may be able to satisfy Both, Load O Matic and Dura Spark II. If it seems correct, don't use it yet. Just do your rebuild of the Carb and do your drive for good performance. Book specs are for the performance as Ford and others want their vehicles to give in every day use and Long Life. There are usually are some tweaks to do get a little more out of an engine without major add on's. Just curious, let me know the List #. Cap