I had my 2BBL carb rebuilt professionally a few months ago and my truck has been running great ever since. This morning, it started up and I was able to drive it, but whenever I would come to a stop and the RPMs dropped to around 6,000 or so (normal idling level) the engine would stutter and then stall. I made it in to work, but she's sitting out in the parking lot presumably awaiting a similar adventure filled trip home.

Any ideas what might cause this? How to correct? I do have my tools with me.

Thanks,
Tim

 

That sounds like a vacuum leak to me. Take a look at the vacuum lines and caps. There could be a loose, cracked, missing or broken one. I have found that the aftermarket hoses and lines are pretty much crap, and they tend to wear out on a pretty regular basis. I always carry a box of assorted vacuum caps in my glove-box, for just such an occasion.

Oh, and what part of Ohio are you in? I have a brother-in-law that lives in or near Goshen.

 

Why did you get the carb rebuilt and what were the symptoms that caused yo to get it rebuilt? The reason I ask is these trucks are getting old, and a lot of them have gas tank problems(rust). You could have had the carb rebuilt because of dirt and rust problems, but later on a dirty fuel system can mess up the carb again.

Once you get it home, pull the aircleaner off and shine a flashlight down the carb throat. If it's really wet and smelly with gas, dirt may have gotten under the float needle and fuel is spilling over into the engine.

 

Good question. The truck had sat for like 6 years without being started. I put on a whole new tank and new fuel lines, new fuel pump.

 

Grub,
I think you're prolly right. I actually broke a few brittle old vacuum lines that wrapped around behind the carb during my reinstallation of the rebuilt carb. The truck ran OK so I never bothered replacing them!!!
I'm in Dayton, OH.

 

If the easy stuff (external items in earlier posts) does not pan out, the next thing to check would be a blockage in the idle circuit of the carb. many years ago my bro-in-law had a similar problem which I traced to a piece of gasket material that had broken off and clogged the idle circuit passages. just because a pro rebuilt it doesn't mean something couldn't be funky internally.