mc 2100 ?'s

just enough

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I have one on my jeep and love it. I have started to look for another one and all the old ford's im looking under have a 2bbl carb that looks just like the 2100 but without the choke thing on the top plate. 6 screws hold the top plate on. Any clues what i'm finding. I've seen this carb on I6 and 302 engines.
 
Could be a 2150 if you're looking at later model vehicles. Though I've never seen one without a choke? What does the tag on the carb say?
 
braxton357 said:
Could be a 2150 if you're looking at later model vehicles. Though I've never seen one without a choke? What does the tag on the carb say?
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It has all the choke stuff on the side but my 2100 has some type of choke mechanizm in the top plate. I'll have to get the tag and post back. Advance auto couldn't help me with the tag info.
 
Jesse, those in the picts are both 2100. the 2150 has a large assembly off the backside of the Carb. what you have there with the "choke" on the top is actually a vacuum Diaphram. not a choke. It's just a different version of the same carb. They are both 2100's.
 
since we are on this subject i have a mc 2100 as well on my 302 and it runs great, exept downhill. it runs pretty smooth on inclines and side to side but whenever i get on a downward slope it wants to cut off unless i keep on the gas. any thoughts? i rebuilt it about 3 months ago.
 
mwilliams. seeing as the float bowl is on the front of the Carb and the jets are in the bottom back of the float bowl, I'd take a look at the float level first off. It maybe set too low and starving. But that It'd have to be set pretty damn low to be honest. Pull the top cover and take a look at how much fuel is in the bowl.
 
mbalbritton said:
no need for a regulator if it's set up right. :beer:
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True, but imo that's part of setting these things up right as well as a springloaded float. You might be right on raising the float rather than lowering though if he's having problems on downhills, but sounds like maybe it's flooding?

Either way, the best carb is still a carb.
 
i have a regulator on there set around 2.5 psi however the fuel pump is a 5-9 psi. do you think it could just be pushing past the regulator? ive checked the float level and it looks normal or maybe a tad high. you might be right on the flooding part cause i tend to have spark plug issues
 
The verbal description of "cutting off" could be either fuel starvation or loading up. getting on the gas to keep it running makes me think that it's fuel starvation. When you get on the gas does it sputter back to life, or does it rev right up?

If it sputters back to life, I'd say it's loading up. and it takes a bit of air flow to get the mixture back right to fire good again and clean the plugs.

If it revs right up, I'd go with fuel starvation. And with the float bowl towards the front, on a decent you're bringing the level of the fuel away from the jets in the float bowl, thus running lean. Gas it and the mixture goes almost instantly back to what it should be.

BUT... all that said, you said that the float level "looked normal, maybe a tad high" to you makes me think it might be something else. Take another look in the float bowl, down at the jets, is there any white cloudy bubbles? if so that's water. empty the bowl, clean it out good, check for debris while you're at it and try it again.

What "spark plug issues" where you having? Wet and black, White and dry? other?
 
on a decent and i give it gas it revs right up to how it should be. the spark plugs are dark and wet making me think there is too much fuel getting past. i have the needles backed out about 1.5 turns which i was told should be optimal
 
well, 1.5 turns is a starting point, not an optimal. If there was as set optimal you wouldn't need idle mixture screws.

setting the idle mixture: Best to do with a vacuum gauge, but you can get it close by ear if you pay attention. Set both at 1.5 turns out. Warm the engine up. when all is good and warm, pinch off the Vacuum Advance hose to the distributor. then back one screw out until you hear a slight decrease in rpms. adjust no more than a 1/4 at a time. Then adjust inward until you reach your highest rpm, but go no further. do the same on the second screw, and repeat until you have the highest rpm that you can get by adjusting the screws. it may take several times back and forth.

If you have a vacuum gauge, connect it to Manifold vacuum on the carb. A vacuum port that is below the venturis. and adjust screws as mentioned above only watch the gauge for the highest vacuum.
 
thanks, i will give that a try as well as look into the other things you mentioned. im still curious about turning it around? will it want to do the same thing on inclines now?
 
mwilliams said:
thanks, i will give that a try as well as look into the other things you mentioned. im still curious about turning it around? will it want to do the same thing on inclines now?
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it may be a good test. But I always figured it was 6 of one half dozen of the other on turning it around. But I guess if you're going up hill, you're on the gas anyway. so it maybe another band aid.
 
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