Fast Idle in Cold weather

[Murphy IRE]

One more thing to add to my list. The tach isn't hooked up (PO), so I can't tell you how fast, but it does vary. The first time was really fast and I had to switch it to an empty tank to shut off, so I keep that tank empty (I have 3). I pulled the carburetor top off and checked for junk in the bowls - NOTHING -perfectly clean. I put it back together and it was better. This week it happened again (not as fast) but all day. I put it in neutral and hard tap the peddle/throttle and it does come down, but it is still a little faster than in hot weather. Should I start looking for vaccuum leaks? Any thoughts or suggestions? Rebuilt 400 sb with an Edlebrock 600

Murphy

[mikey531]

Sounds to me like your choke is not adjusted correct. Is it an electric choke?

[Longhorn Man]

your choke makes it run fast (it's supposed to do that) sounds like it isn't turning off all the way.

[Murphy IRE]

I'll check the choke tomorrow. It is electric and the positive connection needs replacing and the PO grounded it to the insulated carburetor. I'll move the ground to a better spot. I noticed the the two main grounding strap wires are not connected to the engine. They maybe a contributing factor in my starter problem.
Thanks,
Murphy

[Beuford]

Between the choke and the carb is a small weight that is supposed to take it off fast idle when the choke has opened. Spray some brake cleaner on the shaft between the choke and carb and take your finger and move the weights. They should be free to drop when the choke moves to the open pos. Make sure their free.

[68gmsee]

^agree. Spray all moving and swiveling parts good with carb cleaner. Could be gummed up throttle shaft, butterfly valves and other parts. Make sure engine is not hot and let the fumes evaporate off before restarting.

Also, as mentioned above, check the choke adjustment and if needed, take it apart and clean it.

[71tahoe]

Originally Posted by Murphy IRE

I'll check the choke tomorrow. It is electric and the positive connection needs replacing and the PO grounded it to the insulated carburetor. I'll move the ground to a better spot. I noticed the the two main grounding strap wires are not connected to the engine. They maybe a contributing factor in my starter problem.
Thanks,
Murphy

The carburator can never be insulated from the engine unless you use nylon studs. The battery ground should be to the engine and the straps will be for grounding the cab not the engine.

Like everyone else has said, clean it real good, make sure it's adjusted properly, and also make sure the positive has a good connection.

[Murphy IRE]

Thanks for the replies!
The carb being grounded through the studs makes sense, I didn't think of that. I have already re-worked that ground and I did attach one of the grounding straps. It's been way to cold to work on Gertie, but I didn't see the weight on the last warm day (30 degrees). I'll take some pictures. She did start ever time I fired her up to keep her happy.
Murphy

[Murphy IRE]

Finally!
PO had the idle/choke all screwed up. Coloradosean 72 came to my rescue!
We got the tach hooked up and she was idling at 2200 rpm. Timing was close so we backed off a bit and we starting adjusting the electronic choke (no weight on side). Then we did all the adjusting screws on the carb including the link adjustment. Had some problems, so we plugged off most of the vacuum lines and were were able to get everything set. We check hoses and connections and found several leaks. Replaced hoses and I just plugged the line to the aftermarket A/C (i'll fix it next spring they are some leaks there). Perfect- 850 rpm's and smooth.
Took it for a spin and NOW the brakes work a heck of a lot better without the vacuum loss. With the rpm down, the torque converter is pulling, so the brakes aren't haveing to work through that!
TWO birds down with one stone.
Hope this helps the next readerin your quest for restoration!!!!