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Motorcraft 2-barrel carb... F-2 or 2100-D

JoseyWales

Full Member
Joined
Dec 15, 2005
Messages
238
Loc.
Chattanooga, TN
Hi all. I am going to rebuild my original Motorcraft 2-barrel carb. When I started looking at the instructions from the rebuild kit, it appears mine is a F-2 carburetor. I have read the 2100 carb does well off-road on inclines and such, but I haven't read anything about the F-2. Is it as good as the 2100 carb?
 

charliecorbell

New Member
Joined
Dec 9, 2007
Messages
28
Loc.
Huntsville
Just rebuilt a 2150 2BBL. It is running very lean and having trouble getting it to adjust. Plus when I have not run it in a couple of days, I thing the needle valve or float sticks and floods to the intake manifold. Any suggestions.

Also looking for vacuum diagrams for '73 302 standard. Want to return everything stock. I have the charcoal canister. I would love to see pictures.

1. Choke vacuum- temp regulated, passenger side.
2. rear engine tree
3. rear passenger side of carb.
 

PaulS

Jr. Member
Joined
Dec 6, 2007
Messages
96
Loc.
Greater Seattle area
The year of the vehicle that it came off is very important. 1971 and later have mods to the accelerator pump and jets that are two sizes lean for best street use. Those were the original emission carbs. there is a brass plug with a hole in it in the accelerator pump well - it needs to be pluged. The shooters are fine but you also need to lengthen the stroke to the maximum setting.
After replacing the jets, soldering the hole shut and lengthening the stroke (put the rod on the inside hole of the lever on the pump and the outside hole on the throttle end) on the pump you have a carb that is easier to adjust and will run smoother under all conditions.
 

Baja71

Bronco Guru
Joined
Oct 16, 2004
Messages
2,908
The year of the vehicle that it came off is very important. 1971 and later have mods to the accelerator pump and jets that are two sizes lean for best street use. Those were the original emission carbs. there is a brass plug with a hole in it in the accelerator pump well - it needs to be pluged. The shooters are fine but you also need to lengthen the stroke to the maximum setting.
After replacing the jets, soldering the hole shut and lengthening the stroke (put the rod on the inside hole of the lever on the pump and the outside hole on the throttle end) on the pump you have a carb that is easier to adjust and will run smoother under all conditions.

I just rebuilt my 1971 2100 and I'm not sure what you're referring to as a brass plug. Also, before I started the rebuild, my carb was set up using the OUTSIDE hole on the acc. pump arm and hole #4 on the throttle end. All docs told me it should be the INSIDE arm hole and hole #3. Can you clarify?
 

PaulS

Jr. Member
Joined
Dec 6, 2007
Messages
96
Loc.
Greater Seattle area
When you take the accelerator pump off the carb you have the check valve staring you in the face. Just below that orange silicone flapper check valve there is a hole that goes back into the fuel well. In that hole there is a brass plug (unless you are unlucky enough to get one with an aluminum plug) with a small hole in it. When the accelerator pump tries to push fuel up through the shooters, part of that fuel goes through the hole and back into the fuel bowl. Plugging the hole with a bit of solder increases the flow to the shooters.
If you have the aluminum plug you will have to tap it out with a punch and then use a lead rivet to plug the remaining hole.
To increase the length of the fuel delivery you want it on the hole farthest from the throttle shaft at that end and on the pump arm you want it in the closest hole toward the pivot of the arm. So, if hole #4 is farther from the throttle shaft it is better to place the link there. Most of the emission carbs have the link set on the outside hole of the lever at the pump. You can get a longer fuel shot if it is placed on the inner hole.
If you notice a surge (rocking back and forth) when cruising at around 50 to 60 mph or that it takes a great deal of throttle to begin to accelerate from 50 to 60 MPH and then it seems to continue after you have let up on the throttle to cruise then your carb has the lean jets for emission control. Just put a pair of jets in that are 2 sizes larger than the ones in the carb. Presto! You are back to 1969 specs.... in addition to the jet change the accelerator pump mods will also return the rest of the carb back to 1969 specs. It will run smooth and you will notice a marked increase in power and drivability.
You could, of course, just buy a rebuilt carb for any midsize 1969 car with a 302 and get the same thing. I'm cheap, I would rather make the mods than pay for a used carb that may or may not have been built by a professional.
 
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