I have a 1990 wrangler 4.2L 5 speed with an 2300 Holley on it. This is the way I bought it. I had the carb rebuilt and changed the wires, plugs, cap, rotor, and coil. The thing does not run right.. It will not idle. I have a zillion vaccum hoses that need to go somewhere. Am I better off replacing everything with the stock carb or is there a good reason people put Holleys on them.. I did buy the haynes manual for it. But since the carb is different, it does not help much...
I can't completely help you here, but hopefully I can get you started. First off, you need to fix the hoses obviously. A carb cannot properly meter the fuel if the vacuum signal is weak because of multiple leaks. For now, I would have a handful of golf tees handy for plugging the hoses off that don't get hooked up from the steps I tell you. You may also want to pick up a couple feet of vacuum line to make "plugs" with. You can do this with a couple inch piece of hose and a golf tee. Also, if you don't have to pass a smog test, it is a possibility that many of these can be eliminated all together.
The first thing we need to do is hook up a line from the vacuum advance canister on the distributor to manifold vacuum. Find a vacuum port that is below the throttle plate on the carb and hook it up there. It can also be routed directly into the manifold. The next thing is if you have an automatic trans, and it has a vacuum modulator on it, this need to go to manifold vacuum as well. The charcoal canister (if you have one) goes to the large fitting just above the fuel bowl on the Holley. There should be another large vacuum fitting on the back of the carb at the baseplate for a PCV hose. The EGR valve also goes to manifold vacuum, again, if you have one. For now, this should be enough to get you idling so you can at least see if the carb is going to work properly for you.
Plug the rest of the lines with the golf tees for now, and cap off all the vacuum fittings left unused on the carb and manifold. Then turn the idle mixture screws in all the way until they LIGHTLY seat in the hole. Don't torque on them or you'll damage them. Then turn each screw out about 2 1/2 turns. I would set your timing to about 8-10 degrees advanced, at idle with the vacuum advance hose unhooked from the distributor and plugged.
If you have all the hoses plugged, and the carb was properly rebuilt, the engine should run OK and should idle good enough to let you fine tune it. This will at least determine if the carb works decent or not. That carb is basically a front half of a standard Holley 4 barrel, so it is relatively easy to set up once everything else it right.
One other note on the carb, if you had any backfires through the carb while trying to run it, chances are you ruptured the power valve diaphragm. If the engine seems to run very rich, then I would replace the power valve before you go any further. Post back with your findings and we can go from there.
Could this be what is causing my '85 CJ7 4cyl not to start? It backfired several times ...once pretty bad. Now the fuel seems to be flooding the carb, to the point where it leaks out the bottom a bit, and won't run steady. It also smells very rich. If it starts at all, it's VERY unstable and stalls quickly. For more details, refer to the post "What are my likely sources of error".
Maybe I can help on the vacuum stuff. I would be checking the PCV system first. Stock the PCV line comes to the back of the carb to a solenoid thing and from there goes to the carb base and to the charcoal canister.
When the charcoal canister fails, and yours is at the right age, it won't idle any more and usually surges some.
To test, at idle pinch the PCV line from the back of the carb to the canister shut. If the idle changes at all, the canister is dead and the carb will never set stable.
As for the rest of the vacuum crap, here is a link on putting the computer to sleep for a sweet 25% power boost with all the main vacuum stuff listed. Your computer is either properly wired to sleep like the link says or it has gone into 'limp home mode' and clamped down on the timing and things because there is no feedback carb in there anymore.
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It will run like crap with the wrong carb and computer still trying to adjust things.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
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