Beetle dies when braking

[Jack Nel]

Morning all, some advice please.

I have Solex H30/31PICT carb on my Beetle. Starts up easily, idles perfectly, accelerates good and generally works 100%.

Carb was rebuilt rcently by an "expert" and since I got the car back it will start dropping the revs slowly as I am applying brakes to get to a stop and then die. It will start up easily again no problem and run smoothly again.

I've done lot's of reading, checking, adjusting and cleaning, but not winning....

Your advice please

Jack

[slak]

most probably your electronic idle jet is not plugged in or
is faulty
if that is all working good U might have an air leak

[Jack Nel]

most probably your electronic idle jet is not plugged in or
is faulty
if that is all working good U might have an air leak

Electronic idle jet the thingy on the side of the carb that goes click when you take the wire off and put on?
I've checked for leaks by spraying fluid, it is all airtight...

[spicydave]

does it happen even when the car is standing still ?

[Jack Nel]

No, whe car is standing still it runs perfectly, problem only when slowing down while braking

[fig]

Sounds like your idle mixture is too rich. Could also be float level too high. You might also want to check that the needle and seat are sealing if they were replaced. The new Chinese ones seem not to seal even when new.

[John Alves]

I had same problem, what Fig said is most likely your problem, you are flooding the carb with braking inertia

[Jack Nel]

Thanks, I also suspect the float level, will check later

[Edmond]

Had a similar problem turned out to be a heavy/porus float fixed it by raiding the oe float from a spare 34 pict 3 carb I had laying around

[Jack Nel]

So I read that a fix for a high float level is to add an extra copper washer under the needle to prevent the float from raising up to high. I did this yesterday, and my problem persists. I slow down for a stop street while pressing on the brakes and the car dies....
Any more suggestions...?

[John Alves]

Needle and seat are not closing properly.

[retrovan]

....
Any more suggestions...?

Have you checked the float level, or only added washers.??

Does your float actually float ?
Does your needle leak ?
Is the pressure of your pump too high.
Is the problem not broken engine mounts ?
Is your Gearbox earth strap in place and clean connections, ?
Is the connections to your coil thight ?
Had the same problem with the little wire from the points to the connection on the side of the distributor, where the aftermarket wire was crimped on the plastic and every time I went around a corner she would stop but start up strait away after that. I pulled a bit on the wire and she came out, refitted it with solder, and was fixed, still working now.

Herman

[Jack Nel]

....
Any more suggestions...?

Thanks Herman, see below:

Have you checked the float level, or only added washers.?? Checked, but can't find exact levels it's supposed to be, read in one place that level must be 19mm from the top and somewhere else that level must be about a quarter full....The total depth of bowl is about 60mm. Must level be checked with float in place or without and any more accurate info on what level should be?

Does your float actually float ? Yes
Does your needle leak ? No
Is the pressure of your pump too high. Will check
Is the problem not broken engine mounts ? Possible after Sani, will check, but motor has been out after Sani, nothing reported by Mechanic
Is your Gearbox earth strap in place and clean connections, ? Will check
Is the connections to your coil thight ? Yes
Had the same problem with the little wire from the points to the connection on the side of the distributor, where the aftermarket wire was crimped on the plastic and every time I went around a corner she would stop but start up strait away after that. I pulled a bit on the wire and she came out, refitted it with solder, and was fixed, still working now.

Herman

[Tony Z]

does it die as soon as you touch the brakes or only a little later?
If it is as soon as you touch them, then you have an electrical short that is causing your ignition to "go to ground"

[spicydave]

No, whe car is standing still it runs perfectly, problem only when slowing down while braking

What I actually mean is when standing still, idling and pressing brake ?