So I posted earlier here about my carb. I since have gotten a new one, and found my problem was actually the condenser in the distributor. My engine starts and revs like a dream...if only I could drive it! I put it in gear (it's an auto) and it drops in idle, seeming to be too low and dies. Timing was found to be at 10 BTDC. Vacuum test was found to be normal, according to my auto shop teacher. (My car died in the shop at my school, and I've been working on it all I can.) It idles great at 1100 rpms...too high, I know. Tried lowering it down, and anything under 900 it idles rough and wants to die. It almost seems like yup runs too lean, because if you put your hand over the carb, it seems to run more evenly. Another thing is that the shaft that connects the distributor rotor seems have about 1/8th" Ojai vertically, and seems to wear the carbon center in the cap. I have a new ballast resistor and PCV valve (that was leaking before) . Compression tests I did some month back was all above 105.


My teacher is convinced that it is the timing chain (I installed one brand new) that is a tooth off. Thing is, it doesn't hesitate to rev, power (when I test drove it) was better than before the timing chain. And I'm 90% those marks lined up well. I don't mind checking, but it's an hour or more to rip it all apart and I'm running out of time to work. It seems like a Vacuum Leak, but it did this even with all vacuum plugged! It almost seems like it is something stupid again, like the condenser was. Any help is appreciated.

New as in "never been used" factory fresh untouched virginal unit, or rebuilt sold as "factory rebuilt" "remanufactured" or such by a parts supplier? If rebuilt by industrial carburetor rebuilder, chances are good it is junk that won't work well no mater what.

If you have a never been used new old stock, or a carb that is an unmolested original equipment core from a boneyard chances are good it can be made to work correctly with some tuning.

This is a guess, where engine idles in neutral above 1000+ rpm, and drops below 550/600 rpm and stalls when shifted into gear, runs better half choked by your hand, I suspect a vacuum leak, and or improper float level setting, and or idle mixture screw set too lean.

Next on list is distributor shaft may be missing retaining clip which secures and prevents any vertical movement. You will have to pull it, inspect shaft and figure it out. Having distributor shaft ridding up and down will change timing a few degrees.

Timing chain. Did you line up the dots, or did you put a degree wheel on it to dial it perfectly. I have read that sometimes dots are not to be relied on for optimal timing, and can be off enough to effect runability. You could remove valve cover, find TDC using a piston stop, and see if timing mark and TDC agree, if not it may be time to pull off timing chain cover, and use a degree wheel to set it right.

One more thought that probably has been mentioned previously; has the valve lash been checked and adjusted as needed? I realize that engine won't idle down at this point, but you rough in the lash cold with engine not running to get, close just add 0.002" to factory hot settings.

I'm a bit surprised your shop teacher isn't a bit more helpful with a few hints, or does he employ the "Magical Mystery Tour" of teaching where Grasshopper figures it out by trial & error & toil. Frankly the MMT method achieves lasting retention, better understanding of situation, and works best with my thick skull... LOL

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

The carb was a reman from the 80-90's, and never put on a car. Yes, I know that isn't the best, but at the time didn't have enough money to get a NOS.

Timing chain, I figured out after finding that the auto shop class the next hour had pulled almost everything off, so I finished the job and checked the chain. Perfectly lined up! Distributor lines up, and dots line up. Degreeing the cam...I have seen it, but am slightly nervous to do it because I wouldn't want to screw it up. Timing set is a Cloyes set.

For vacuum leaks...I will button everything back up and plug up the vacuum sources again, plugging up one by one to see if I can find any sort of leak. Also will have a can of carb cleaner handy!

Distributor I will check for, but that seems to be the only thing wrong with it. Points were set for .017", everything else is good.

Valves I set the lash for if needed when warmed up after a camshaft break in.

My teacher is extremely helpful in trying to figure out the problem. I think he wants my car outta there partially, haha! But he has been helpful, but carbureted and anything older than OBD I is not his strong suit.

Year of vehicle? Ignition system that is installed? Type of carburetor being used?

If it won't idle around 700 RPM then there is a problem. If the idle smooths out when you choke it (hand over the throat), there is a problem.

Sounds like you need to spend some time tuning the carb. Idle mixture and curb idle speed would be where I would start.

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Casually looking for a Clifford hyperpak intake for cheap.

Whoops, I failed to list that. 1972 Dart, points ignition, and a year 1970 Holley 1920.

That will be the first thing I will be looking for is the carb adjustments once everything is put back together. I will have the vacuum gauge and timing light hooked up to watch for changes.

Do you have the Holley list number perchance? (hint....)