Viich

iTrader: (1)

So, my 82 won't idle. Stock exhaust, air pump still on.

It will start and warm up with the choke on, but then immediately stalls. It has done this for some time. My first thought was vacuum leak, especially as I KNOW the shutter valve is bad as there was a large honking sound for a while.

Shutter valve is gone, holes plugged. Carb now stripped as per Jon's tutorial except that I left the choke & ACV on. Vacuum secondaries gone, altitude compensator, throttle puller and front and rear choke assemblies. Symptoms are the same.

I'm down to three spots it probably is if it is a vacuum leak. Either it was the shutter valve and I need to check my sealing of the manifold, or it's either the ACV (I guess removing it is on the list now) or the brake booster or line. I guess it could be the manifold to engine gasket as well, but it seems less likely.

I've got two possible next steps.
1. block off all vacuum lines (advance, brake booster, etc) and see if the problem goes away.
2. take the carb off again, check everything I did, and go the extra steps of removing ACV.

Anything I'm missing? Especially something obvious?

t_g_farrell

iTrader: (1)

Well when the choke is on your getting a richer mixture and apparently rich enough to idle fine.

So it did all this before you stripped the carb? I would make sure basic things like fuel flow is
good, pressure is good, fuel filter is clean etc. Then I would move on to the carb itself.

How do you know its a vacuum leak? Can you hear something? Did you use a vacuum gauge and
see bad, unstable readings? Are your float levels good?

Does it run if you manually hold the throttle open when its warmed up? Could be your idle
circuit is plugged at some key passage.

Cookboy

iTrader: (10)

Sounds like my 1st strip/rebuild. I took it apart again and blew out all passages with carb cleaner. Then it worked fine.
I also learned about that time of the importance of regular fuel filter replacement. And cleaning the tank if you haven't.

NCross

iTrader: (18)

When you strip a carb you usually have to bump up the idle a bit. Make sure your vacuum advance is ported to the right base plate port.

Viich

iTrader: (1)

It had all these symptoms before I touched the carb. Fuel flow is great, I checked it after putting the carb back on.

Float levels look fine. The fact that it will run on choke, but not otherwise is what made me suspect vacuum leak. It would run if I kept the RPM up over 2k, haven't driven it since I started messing with the carb.

NCross

iTrader: (18)

Make sure your jets and bleeds are clean, and that your throttle plate and linkage clearances are within spec and not tampered with.