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Cp2295
01-11-2014, 12:40 AM
Got an 81 2.6l mighty max, original carb and all. The thing idles at like 3000 rpms and when it's first started in the morning it misfires like crazy, hesitates a bunch, but goes away when it's warmed up. But the high idle starts once it's been driven a few minutes. At first it doesn't idle so high. I looked at the carb a bit but that thing is insane with all the lines... Overwhelming! When I push on the plate on the top (the barrel closest to the driver fender) the idle slows down.. Idk if it's the choke, I don't know how this crazy thing works! What can be the cause of this issue? I also get like 10 mpg at most. Can I get a different carb? A weber? Edelbrock? Etc, just something that is easy to tune and has a manual choke. Also the thing ticks like crazy like it needs valves adjusted.. Anyone know how? Truck only has 60k on it. Nice toasty brown plugs, doesn't smoke at all, so it's worth the trouble to me!

thanks in advance!

-chris

Cp2295
01-11-2014, 12:42 AM
It's definitely probably off factory settings. As far as the carb specs go. I'm new to carbs so if anyone can teach me the ropes that'd be greatly appreciated. I know it mixes the fuel and air in there and it sends it down the intake manifold, and it has ports and jets and all this stuff to mix fuel and air at different speeds. But I'm confused about how to tune it and all..

pennyman1
01-12-2014, 01:38 PM
Replace the carb with a Weber - the choke sounds like it is bad and on the early carbs they are not replaceable. The weber is the carb you want for tunability, and your gas mileage and power will soar over what you are getting now. Geronimo has had a weber carb for over 30 years, so it is a long term improvement.

Cp2295
01-12-2014, 09:47 PM
Which weber should I get? Do you have a model # by any chance?

pennyman1
01-15-2014, 06:41 PM
32 / 36 dgev / dfav difference is where the linkage is in relation to the carb bowl, but both work the same. Get a "real weber" made in spain - not the shiny knockoff out there from some places - read the threads for more info on that.

Law Dog
05-15-2014, 09:11 AM
Had the same issue after switching a car out that had bad MPG the new carb is a little better but had a fast idle, if I pushed the throttle downward the RPMs went back where it should be at. I ended up drilling a small hole in the edge of a fender washer and adding a small return spring and mounting the thing in an unused hole in the intake manifold below the carb, by hooking the other end of the spring where the cable ball hooks the throttle cam it fixed it. I just wonder it the throttle return springs don't get weak over time!

zottic
05-29-2014, 10:57 AM
I put a factory rebuilt carb on my 86 Ram 50 then took it to a pro for adjustments and smog. He said high idle is normal, anyway he couldn't adjust it either.