help with motorcraft 2100

help with motorcraft 2100

hopefulcj

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Location
north florida
Vehicle(s)
1980 CJ7-258 I6, MC 2100 carb, team rush upgrade, T4, D300 tcase, D30 w/aussie locker in the front, AMC20 open, I think PO put 4.88s in the diffs, 35,000-135,000 miles, you pick. 4"susp lift, 2" shackle, 35" A BAD WORD cepek AT's on black steel wheels, 1 1/4" spydertrak wheel spacers, most everything else i believe is stock, finding things out as I go
Im so frustrated right now, I bought the carb/distributor package from the guy on ebay. At first everything looked great, he said it should just be plug and play, its been the opposite of that. I have double and tripple checked just about everything on the carb, however I am new to carbs. After the install and checking all the bolts I started it up and sprayed some carb cleaner around the carb and the hoses that I plugged, no change in idle. Its a 1980 CJ so I did not have to do the nutter bypass. I got it running, and it ran fine, I adjusted the timing to 8* and tuned the carb with a vacuum gauge, I got about 16 psi on each side. I took it for a spin and it ran great, smooth as a baby's bottom. Then the idle went down at a stop light, I had to pump the gas to keep it running. So I went home and checked the timimng, and carb, I had to adjust the idle on the carb, and in turn re-adjusted the timing ( yes I did unplug and plug the vacuum advance to the carb) at around 750 RPM. (this amazed me because with the carter, I could never get it down to 750 without bouncing all over the place) Anyway, I checked and cross-checked all the timings and tunings and RPMS, all were good. I took it out today and everytime I acclerated it wanted to die on me, I had acclerate very slowly to get any movement, I got a backfire or two out of the intake. I took it home and took off the intake and noticed that the butterfly is all the way open, even with the engine off. This is wrong right? I can push on the butterfly to close it and it springs back open. Is this incorrect? It should be closed when the engine is off right? I remember reading about how you have to switch the choke spring on some carbs, is this the culprit? When I got hoem and loooked at the carb their was no tension on the butterfly so I assumed that something was messed up, I took the choke off, reinserted the butterfly arm into the choke spring and also turned the choke so the butterfly would close. My dad just told me that I should not mess with the choke when the engine is hot, this makes sense now. Where should I begin? Its sitting in the garage cooling off now. I thought I had it, and now its all messed up, Im close to calling the mechanic, but I need to conquer this on my own, for man reasons.

Thanks for any help, sorry for the long post, just confused right now, kinda new to carbs.
 
the choke butterfly should be open completely when the jeep is warm. the choke will close on its own when the jeep is cold if you have an electric, or climate controlled choke. do you know what type of choke is on the carb?

here's a little reading for you, http://en.wikipedia.org/wiki/Carburetor#Choke
 
Its got a electric choke on it, I tested the wire plugged into it, and it is getting electricity. I was under the impression that the butterfly only opens when the engine is revved. Im gonna go back out and "spray" some propane around the carb and vacuum hoses to try to find any leaks. Their isnt to much power when I accelerate, and if I really get on it, it starts to bog down. Is this simmilar to a vacuum leak?
 
No when the engine is running and warm the choke, (the butterfly at the top) is supposed to be open otherwise it will choke off air to the engine, and make it run rich, it it runs long at all. Now the throttle butterfly (in the base of the carb) is supposed to stay closed until revved, that is the one operated by the accelerator pedal.

Droooiiddd 2
 
I finally got it. Thanks for your help cheapjeep. The rimig was off. I remember were the mechanic ser the timing before when it was running well. I the notch on the flywheel was pointing straight up. I I bent a rod guide/bridge and he said that that might have messed up the initial timng. So after setting the timing to 8*btdc the jeep ran right :dung:. I chased gremlins forever and finally went back tithe timing, it was bugging me all day and night through class. The I got homeland babies around the block, an adjusted the timing and it runs great again. I adjusted the carb with a gauge, but it looks like 2 turns out is perfect.

No more headachesbfir how. Thanks again.
 

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