My 77 CJ7 has run for years without any attention, not that I put any great miles on it. This summer it decided it was going to be difficult, so now I have to remember how a carb works, with very small success.
I took it all apart and cleaned it, and blew out the jets. Put it all back together and tried it, no dice. When I come off of throttle, it dies unless I very carefully feather it down to idle. I’m clueless about what’s wrong, and have run out of dead chickens to wave over the necromantic device.
I think it would be less trouble to pull the engine and put in a spare 4.0L I have on the shelf.
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When you took it apart and cleaned it, did you put a new carb kit into it? People talk lovingly about the older generation of cars, but the thing they skip over is all the wearable parts. As in parts that are fully expected to just wear out and stop working. There’s tons of them too in old generation cars!
For your case a carb kit would replace all the gaskets, seals, and give you a new needle and seat. This became a kit because all these parts get old and brittle and wear out. Because the carb is a precise device that depends on the vacuum of the engine to operate, any tiny little gasket leak or poorly closing value causes all manor of performance problems.
I didn’t but the carb is pretty low-miles. I might have put 500 miles on it in the 10 years since I replaced the carb. I did blow it all out and cleaned out the float bowl. Maybe I missed blowing something out.
Sounds like a vacuum leak if it runs with a wide open throttle, but doesn’t idle. Look at all the hoses attached to the intake manifold below the carb. Also if your brakes feel hard to press it could be a leaking vacuum booster (if it has power brakes).
Usually it’s a missing plug or cracked hose in the vacuum lines. (PCV, distributor advance or brake booster).
Edit: I’m assuming this is a Carter YF/YFA carb.
Vacuum was 19 inches so that seemed ok and I got no stumbles spraying carb cleaner around.
ended up using a mc2100 out of an old Ford pickup in the farms dead car alley and putting a kit in it. Now I have to manually choke it but that’s just one less thing I have to investigate when it craters next time.
So it was the carb I guess, I’m not a big fan of Carters seems like they’re always adjusted to hell when I come across one.
