Name that Carb

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mpbsr

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My 2b isn't oem and I've been having trouble with the electric choke not working properly. So the idle stays high (around 1100-1300) no matter if the idle screw is adjusted.

The only marking on the carb that makes any sense is Motorcraft.

So can anyone here at least tell me 50% sure that the carb is a 2100D or another model?

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imusa76

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either the 2100 D as Jeff said, or its a Motorcraft 2150

 

Hemikiller

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The idle solenoid looks like it is extended, have you tried disconnecting it (or removing it) to see if your idle drops? It's there to bump the idle up when the A/C is on.

 

Mister 4x4

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I have the same carb on my '80 Jeep CJ-7. Really woke up the 258 I-6.

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Unless you absolutely need it (for A/C idle control or emissions, or whatever), I would remove the electric idle control solenoid as Hemikiller suggested.

 

Hemikiller

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That carb has definitely been monkeyed with, the screws are not Ford issue for sure. Having messed with the 73 carbs before, my initial thoughts are vacuum leaks, mis-adjusted linkages, or tuned improperly. My first step would be to spray carb cleaner around the base of the carb, on the vacuum hose connections and any other place where you might find a leak. If there's a vacuum leak, the carb cleaner will get sucked in and cause the engine rpms to change. If that yielded nothing, my next step would be to adjust the timing and idle speeds according to the procedures in the manual. Plug the requisite vacuum hoses - golf tees work great for this and you can get them in different colors to help with id, set the timing to the factory spec, then set the idle speed and re-check the timing. The choke looks like it is operating properly since it's fully opened, so I doubt it's the thermostat. IIRC, there should be a choke vacuum pull-off mounted to the rear bolt behind the t-stat on the 73 351C 2V engines. That could cause some issues with the choke operation, but I don't think it'll affect idle speed.

 

mpbsr

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That carb has definitely been monkeyed with, the screws are not Ford issue for sure. Having messed with the 73 carbs before, my initial thoughts are vacuum leaks, mis-adjusted linkages, or tuned improperly. My first step would be to spray carb cleaner around the base of the carb, on the vacuum hose connections and any other place where you might find a leak. If there's a vacuum leak, the carb cleaner will get sucked in and cause the engine rpms to change. If that yielded nothing, my next step would be to adjust the timing and idle speeds according to the procedures in the manual. Plug the requisite vacuum hoses - golf tees work great for this and you can get them in different colors to help with id, set the timing to the factory spec, then set the idle speed and re-check the timing. The choke looks like it is operating properly since it's fully opened, so I doubt it's the thermostat. IIRC, there should be a choke vacuum pull-off mounted to the rear bolt behind the t-stat on the 73 351C 2V engines. That could cause some issues with the choke operation, but I don't think it'll affect idle speed.

Good suggestions, but you do realize that it's a 302, not 351. Plus like I previously said, not OEM. So yes it's been monkeyed with before.

 
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Hemikiller

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That carb has definitely been monkeyed with, the screws are not Ford issue for sure. Having messed with the 73 carbs before, my initial thoughts are vacuum leaks, mis-adjusted linkages, or tuned improperly. My first step would be to spray carb cleaner around the base of the carb, on the vacuum hose connections and any other place where you might find a leak. If there's a vacuum leak, the carb cleaner will get sucked in and cause the engine rpms to change. If that yielded nothing, my next step would be to adjust the timing and idle speeds according to the procedures in the manual. Plug the requisite vacuum hoses - golf tees work great for this and you can get them in different colors to help with id, set the timing to the factory spec, then set the idle speed and re-check the timing. The choke looks like it is operating properly since it's fully opened, so I doubt it's the thermostat. IIRC, there should be a choke vacuum pull-off mounted to the rear bolt behind the t-stat on the 73 351C 2V engines. That could cause some issues with the choke operation, but I don't think it'll affect idle speed.

Good suggestions, but you do realize that it's a 302, not 351.
Doh! No vacuum pull off on the 302... :whistling:

Something else to do, pop the linkage off the throttle arm and see if it helps. It looks like there's an aftermarket ball stud on there, they might have put it in the wrong hole on the arm.

 

judge

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There should be a number stamped in the front left foot under the solenoid. It's not the part number. But it can get you to it.

 
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I'm almost 100% sure that your solenoid is not for AC, rather it is an anti diesel solenoid. The proper setting is done by backing it off completely so that the idle screw is functioning and set your idle, then turn the solenoid in to hold the idle there and back the idle screw off several turns, so that when you kill the ignition, the solenoid closes, the throttle closes and run on is prevented.

I use one made by Holley on my engine for that very reason, it is a big help when trying to run 11.5:1 compression on pump gas

 
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Hemikiller

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Jeff is correct, it is an anti-dieseling solenoid. I apparently got my wires crossed with another car...

The solenoid should be active when setting the idle, then you unplug the solenoid and the idle should drop to about 500rpms.

I don't have a 73 ford shop manual, but can scan and post a PDF of the '72 section to adjust the carb. It's really easy once you know the procedure.

 
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