[tdfisher]

Hi all - I think I have an issue with the idle mechanism in my 1964.5. Engine is 260, 2-barrel carb. Car takes about a minute to turnover on ignition. Once started up, I need to slightly depress the accelerator for about 30 seconds or so to give it enough gas to keep running. Sometimes, this is enough to get the car ready to run. Other times (more often than not these days), when I take my foot off the accelerator, the car stalls. This has happened to me at stop lights before as well, which can be an embarrassing event... Anyway, the other day I couldn’t get the car to keep running long enough to reverse out of a parking spot. I called a friend who told me it may have something to do with the idle mechanism. He walked me through adjusting the screw on the dechoke linkage assembly to “open up” the fast idle a bit so it didn’t close when I took my foot off the accelerator. I noticed there is a piston attached to the dashpot that slides in and out. I’ve been playing with this a bit trying to find the right solution, but I’ve yet to fully resolve the issue. I have also noticed that most dashpot assemblies online have a spring, but mine appears missing (if was ever there at all to begin with). I wonder if I need to replace this dashpot or the dechoke linkage assembly, or both. Even better would be if there is a quick fix with what I currently have in place.

Photos attached.

Thanks all

 

[kenash]

For cold start, one typically depresses the accelerator a couple of times. This engages the choke plate that closes. If all ie working as it should, the engine will crank, fire and idle a few hundred RPMs on the Fast idle cam, then, as the engine warms, the choke is gradually pulled open via a heat tube off the exhaust manifolds. Once all of this happens, when you drive off accelerator linkage at the carb kicks off the Fast ideal cam and the engine is in “normal” mode. That is, it should “idle” at your recommended setting. The stalling at a light, for example, could be that your “dashpot” is failing to allow the idle to gently “settle”.
Forgive me for this lesson, but, so many younger folks have little experience with these old carb’d cars. Anyone of the “ systems” I mentioned needs to be checked for proper working order. Start by performing a complete tune-up check, then look at each of the systems. Hopefully, I didn’t miss anything.