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Sun Jun 09, 2002 2:59 pm

Is the choke adjustment on the 72 Super Beetle the same on a 73

Sun Jun 09, 2002 5:06 pm

It is basically the same on all the solex carbs that came with the electric choke....
there were however different #'s on some like 60 or 78 or some with none at all. Needs to be turned Counter clockwise to tighten it up a bit for summer and backed off for cooler/ winter weather.... Check it stone cold in the early am....and set it then...
Remove the whole element and make sure the carb has the black plastic piece behinnd it, it won't work right without that being there... Warm the car up and drive it and make sure it goes "off" all the way and that on the 34 pict3 the screw on the arm does not or just barely touches the choke cam when it is off...

Thu Jun 07, 2012 3:38 pm

I have a 1973 standard beetle with 1600 dual port, Solex 34 Pict 3 carb, with electric choke. When I start the engine cold, choke is fully open and gradually steps down on the choke cam as designed. Runs perfect when choke shuts off for extended period at idle. Problem is, once I step on the gas, the choke will step up one notch on the cam and then the engine stalls. Does this mean the choke is set to rich??? What would be the fix??? I'm new to the VW world. The engine is completely stock with fresh points, plugs, wires, vac hoses, fuel pump, oil change, electrical wires, clutch, valve adjustment, rebuilt carb, gaskets, etc. All tin, heater boxes, etc are intact. Only thing not working is the preheat flat in stock air cleaner. This car will only be driven in PA summer weather. The engine work was all done by an old VW mechanic when the motor was out of the car approximately 1 year ago, prior to me purchasing the car. I currently have the entire frame restored and engine reinstalled. Thanks in advance

Thu Jun 07, 2012 4:31 pm

myrenovator wrote: I have a 1973 standard beetle with 1600 dual port, Solex 34 Pict 3 carb, with electric choke. When I start the engine cold, choke is fully open and gradually steps down on the choke cam as designed.
A cold choke coil should be trying to CLOSE the choke butterfly. Before starting the engine you should step on the accelerator pedal enough to release the throttle arm's hold on the step cam. The butterfly should slam shut on a fully cold engine.
Once the ignition is ON the choke coil starts to heat up and the butterfly will start to OPEN. As it opens the cam will rotate and the throttle arm screw will rest on progressively lower steps.

myrenovator wrote: Runs perfect when choke shuts off for extended period at idle. Problem is, once I step on the gas, the choke will step up one notch on the cam and then the engine stalls. Does this mean the choke is set to rich??? What would be the fix???
It could be your choke coil is old. After years of heating/cooling they loose their range of motion. My old choke coil would not close enough when set to few fully open when warm. If set to fully closed when cold it would not open enough when warm. A new coil fixed that.

There is also a vacuum activated piston that forces the butterfly OPEN (I think?). I believe the function is to open the choke butterfly when increased flow is needed.

Fri Jun 08, 2012 2:59 am

Ok thanks, I will check the choke coil. I meant to say choke is fully on/closed when I start the engine cold. The butterfly valve is fully shut when I step on the gas pedal and set the choke, prior to starting the engine cold.

Fri Jun 08, 2012 9:27 am

myrenovator wrote: Ok thanks, I will check the choke coil. I meant to say choke is fully on/closed when I start the engine cold. The butterfly valve is fully shut when I step on the gas pedal and set the choke, prior to starting the engine cold.

no it must not be fully on.
not fully closed. not in summer. the ambient temp effects that coil too.
and when you step on the gas the chock vacuum unloader keeps you
from flooding the engine. it too must work..

yes, the op guide, in thechnical tab above., is clear, if your read it.

you must press the gas pedal, once to unload the choke.
do so by and watch it , make sure it works.

1: dead cold motor , last run fully hot , not messed with at all.
2: open rear hatch.
3: look at choke, its 100 % open (due to last hot run)
4: grab throttle there, BLIP IT.
5: see chock reload and close 75 to 80% a 1/4" gap for air on fly plate>
that is the summer effect the bi-metal spring is effected by ambient temps.
see high speed choke cam , go to higher steps (mine goes to 3 in summer)
6: the car starts. and it opens as you drive.
in alaska it will close more.

next idea
Quote: turned Counter clockwise

turn the CW ,for summer.
see the scale on top (look)
turn it (3 screws loose) to the right index mark , that be lean for summer.
i run mine lean all the time. (John Muir had it right, but was to extreme)
since 1964, and most cars i had a manual choke, far better that.
on vw the cables are a pistol to install. sadly

the less choke the better. set it like ,YOU LIKE IT.
bettery answer, sit it like you ENGINE demands.
each motor is different. (got low compression, DIFFERENT)
as is the climate and seasons.
and the type of gas you run (seasonal changes)
each choke coil (a bi-metal spring) is different by brand, or age,
so are the carbs different some run tad rich or lean, and choke is effected by this FACT. (and air leaks in the throttle shaft too)

its just a very crude device. not like EFI.. not even close.

Sun Jul 28, 2013 8:27 am

Are the 34 pict heating elements interchangable from the ones marked 78 to the 60? I installed a 78 to where a 60 was and it seems to be working. I dont see the marks on the 78 so I turned it till it closed the butterfly closed and tightened it up. When the car is at operating temp and the butterfly is fully open is the throttle screw supposed to go off the last step on the cam?

Sun Jul 28, 2013 12:09 pm

The "78" choke element is a pre-72 part that takes a little longer to
open, but is otherwise the same as all other 12V choke elements. If you
adjusted it till the choke butterfly was all the way closed, you adjusted
it too far (for this time of year). When fully open, the throttle plate
adjusting screw should be "below" the first step on the choke cam,
barely touching + 1/4 turn.

Mon May 22, 2017 4:47 pm

ashman40 wrote:
A cold choke coil should be trying to CLOSE the choke butterfly. Before starting the engine you should step on the accelerator pedal enough to release the throttle arm's hold on the step cam. The butterfly should slam shut on a fully cold engine.
Once the ignition is ON the choke coil starts to heat up and the butterfly will start to OPEN. As it opens the cam will rotate and the throttle arm screw will rest on progressively lower steps.

Thanks, Ashman40! This fundamental explanation was exactly what I needed. My choke was at the recommended setting, but was only moving the butterfly less than half way. After an adjustment the cold engine started right up the first time for a change. And after a drive around the neighborhood to warm up, I was finally able to get a steady idle in my driveway and later at a stop light.

Fri Jun 16, 2017 4:45 pm

Justed reading all the good information about Solex chokes but did have one question......
Since the 1960's, being a good "Idiot" ( from the title of the idiot guide. ; ), I usually open my choke each summer and let it warm up without it, putting up with rough idle until warmed up. I know some of the advise in the book wasn't the best.......Was this bad advise and should I use it in summer,but just adjust it looser, and not unwind it completely keeping it open all the time ?

Fri Jun 16, 2017 5:25 pm

The Idiot Book made a big mistake here. When summer comes, I readjust my choke so that it is almost closed. When e weather cools in winter, I adjust it back. It just takes a few minutes.

Even in the hot summer, your engine is cold before the first startup. Cold, as far as the engine is concerned, that is. In summer, since my choke is readjusted for warmer weather, the ambient heat, coupled with the electricity, opens the choke in good time.

Why John Muir was down on chokes, I have no idea. But his attitude was probably based on old-school thinking gone awry.

Tim

Fri Jun 16, 2017 6:24 pm

Is it worse for the engine without the choke since, to keep it running, one tends to pump the accelerator pump washing the cylinders in raw gasoline.....Does it put more raw gasoline into the cylinders than a partially closed summer position choke ? Or is it simply that the warm up time is quicker with the choke and both put about the same amount of raw gasoline on to the cylinders ? I wonder what was on john muir's mind ?

Sat Jun 17, 2017 6:24 pm

The choke allows the engine to run rich until ot warms up. What its doing is cutting off air coming into the carb and the mixture is richer, hence no rough running. As the engine warms the butterfly opens and then it should run as normal. The key is really to get the engine warm before the choke is fully open. Why back bit all the way off and stutter??