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Sat Dec 19, 2015 1:21 am

Getting to be in the 15-30 degree level here in Denver (Lakewood) area. Temp here goes up and down. I set the full auto choke on a cold day and have been left cranking a bit after starting fine from a cold start.

Choke works great on a fully cold engine, 30 minutes in a store and returning I have problems.

I removed the choke entirely and it starts fine apart from having to stay on the gas for a minute.

I am thinking of setting it halfway but the temp varies so much here, should I just forget it and plan on staying on the gas for a minute when I start in the morning?

Sat Dec 19, 2015 3:26 am

The automatic choke should function well over wide range of temperatures once it is set properly. Just keep making minor adjustments to the choke coil setting until the butterfly opens at the correct rate. The unloader may need to be adjusted as well.

I block off one of the corner post inlets during the winter months so that wind doesn't blow through the engine compartment and cool the engine off as quickly during short stops. This makes restarting and the first minute or two of driving that much more pleasant.

Sat Dec 19, 2015 6:10 am

The 34-3's are sensitive to finding the sweet spot for the chokes. If you crank them too tight, they seem to not get enough air through the choke plate and struggle for a bit during the first start. I found that you have to have a reasonable crack in the choke plate 1/8" open for it to start and idle up on the choke. I remove the air filter tube and use a mirror to look down the barrel of the carb while setting it. This seems to leave me with the notch on the choke almost in the middle of the three lines or just short of it.

When I do some short runs and get back in after a errand, I immediately floor the accelerator pedal to open up the butterfly and get as much air into the engine and then turn the engine over. It starts quickly doing this. This procedure is in most owners manuals as well.

Sat Dec 19, 2015 10:17 am

Where I live temps go up and down like a yo-yo. It was 13*C here yesterday and today it's only 3*C. I disabled the chokes on both of my Beetles. Three pumps of the gas pedal and they start right up. Feather the gas for 30 seconds to a minute and they're good to go.

Sat Dec 19, 2015 12:20 pm

start with the specs in Bentley. It will also be affected by what size mains you have and closely your idle mixture is adjusted. The world is not perfect and these old carbed buses did not perform as well as a modern FI system.

That said, a good mechanic can fine tune a 34 pict 3 to where it runs well in all environments. I never had any issues keeping mine working well unless a choke got sticky, or the element burned out. A sticky mechanical advance in a distributor can show up too in cold weather.