258 stalls at idle

My fuel lines don't go near there. Just checked.

Well everyone, I solved my own troubles. My carb is two weeks old, it can't be broken, right? Wrong. As a last resort, I pulled the venturi cluster, found that my drivers' side idle pickup tube had fallen out of its hole. Cleaned 'em both up for good measure, pushed the one into the assembly, and put everything back together. Started it up, and it just purred. On the bright side, in the process of fixing this thing I fixed a vacuum leak and tested most of my emissions stuff - so everything should be working fine for a while now.

Going to take a shower and get to the grocery store - Haven't been there since this started happening and I'm getting pretty hungry.

Thanks for your help, Bill.

The gas line from the filter to the carb has a U shape and is notorious for holding enough junk in it to plug up an idle tube. I see that lots just after a carb kit job if folks don't clean that line out.

To see if this is it, at idle carefully look down the carb throat and give the gas a shot with your hand on the linkage. You should see two nice sprays of gas in there. If you see drips of gas, then the idle tubes are plugged up.

Here is a link on fixing that problem. The idle tubes can be pulled from the top if the choke plate is out of the way and cleaned. They twist and clear the choke rod also. They need a physical ream at the crimped end or better an oversize using a welding torch tip tool. Those are small drill bits or files.

Mike

Just adding a note about a FREAK happening that just about drove me wild!

When I got my 86 CJ it suffered from the common malady of the NOX reduction "enrichment system" causing it to load up and die at idle. Being an "old geezer" from before the EPA forced Carter to ruin the BBD, I simply modified my BBD carb to eliminate the useless "enricher motor" on the rear and re-set everything to old style specs while also performing the "Nutter Bypass" to eliminate the no longer used circuitry.

The CJ ran flawlessly for about 3 years and then started sputtering at idle. "What the...?", I thought. So all through the carb I went searching for the culprit. Found it floating around under the "idle tubes". Where did this piece of flotsam come from? I found that out as well, starting the Jeep and letting it run with the lid off the air cleaner during adjustments I noticed that the "Air Injection" hoses that branch off the back of the cleaner went through a stage during warmup where they sputtered a little condensate back into the air cleaner housing. Amongst that condensate were some tiny flakes of "crud" just like the one I had removed! If one of these just happens to make its way over to the float bowl opening, it will eventually find its way to the "idle tubes" and repeat the problem. I know it is a "long shot" but it was the logical reason for the problem considering the surgical clean rooom method I use when tinkering...

Those little problem makers are now disabled, and I don't plan on tearing apart my BBD for another 10 years or so until the pump and needle are tired!

Bruce

I find I need to clean my float needle and seat every couple years. I also needed emissions every couple years so I would normally just kit the carb for $20.00 and have everything new. Those are really easy carbs to kit.

I 'think' I know one source of your black chunks in the float bowl.

If you run that 258 engine out of gas when warmed up, the charcoal canister is active because of the hot coolant in the CTO valve. Then when you are trying to start it up, the choke will automatically be closed which puts high vacuum on everything which will sometimes suck charcoal bits out of the canister.

I have had this happen to me and have seen it happen to others. One person from this group I think it was put a clear inline gas filter in the vent line to the carb float bowl to prevent this from happening. He reported finding bits of charcoal in the filter.

Mike