yet another problem (video)

[jacksonp32]

i need some help sorting an engine shake/idle problem. when i adjust carb and set timing it will run great and idle mostly okay (just some engine shakiness), but after i let it run for a few more minutes, the idle ends up being low and the engine is struggling to stay running (around 700rpm). And so i resort to running a higher idle, but then get a problem with the engine speed rising and falling as seen in the video... i checked for vacuum leaks and found nothing. any ideas for what could be causing the engine shakiness and idle issues? if you need more info or another video from a different idle or anything let me know! thank you all in advance

info:
1600dp
34pict3
original bosch 034 w new points/condenser
new plugs and wires
timing set to 7.5btdc at 900rpm




https://youtu.be/NzfZtmWiOzM

[67rustavenger]

You have a vacuum leak at the back of the carb. Just above and to the right of the dime sized plug on the rear (rear meaning rear of the car) of the carb. Usually there's a brass connector sticking out at that location. Yours is missing. Plug that hole and see if things improve.

Good Luck.
_________________
I have learned over the years.
Cheap parts are gonna disappoint you.
Buy Once, Cry Once!

There's never enough time to do it right the first time. But there's always enough time to do it thrice.
GFY's Xevin and VW_Jimbo!

[Knusprige Flicken]

[sb001]

I think there's a bit of confusion as to what I posted regarding that drilling for the autostick port.
I am fairly certain (although not 100% sure) that at a point ALL the Solex carburetor body molds had that provision for the extra autostick port, but it was actually only drilled out if it was going on an autotick. If the car was a stock 4 speed, the port wasn't actually drilled out--it's still solid inside that hole. I could be totally wrong though.
The absolute best way to be sure is to look and see if there is a modifcation number either on the float bowl or on the base flange of the carburetor (for example my 30 PICT 3 has the "227-1" modification number on it.) If it was indeed an autostick carburetor, it would have a modification state number. Here is a list of a few modifcation state #s for autosticks (with the correct matching autostick distributors and proper jet sizes):


VW 227-1 30PICT-3 113905205AD/ 113905205AE Bug 1600 SP 8/69 112.5 140z 65 Autostick
VW 281-1 34PICT-3 113905205AH BUG 1600 1971 130 75z 60 USA Autostick
VW 281-2 34PICT-3 113908205AH BUG 1600 1972 127.5 75z 60 USA Autostick
VW 281-3 34PICT-3 113908205AH BUG 1600 1972 127.5 75z 55 California autostick
VW 281-4 34PICT-3 113908205AH BUG 1600 1973 127.5 75z 55 USA Autostick (Generator accelerator pump)
VW 281-5 34PICT-3 1139008205AH BUG 1600 1973 127.5 75z USA Autostick
VW 343-4 34PICT-3 113908205AH BUG 1600 EARLY/MID 1973 127.5 75z 55 California autostick
VW 428-1 34PICT-3 043905205A BUG 1600 1974 127.5 75z 55 USA Autostick
VW 430-1 34PICT-4 043905205A BUG 1600 1974 127.5 60z 55 California autostick
_________________
I'm the humblest guy on this board.

1969 autostick sedan, family owned since new
1600 SP engine
Solex 30 PICT 3 carburetor
Bosch 113905205AE autostick distributor

[mukluk]

More often than not the behaviour your engine is exhibiting is due to a problem with the idle mixture. The caveat here is carburetor adjustments should always be the very last thing you perform when tuning, and only after the engine is fully warmed up. Before going any farther you should do a proper valve lash adjustment, verify spark plugs are gapped to .028", adjust dwell, and adjust the timing.
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1960 Ragtop w/Semaphores "Inga"

[jacksonp32]

just to clarify, the port you were looking it is closed- not drilled out or anything. Inside is just solid. and as for the carb adjustment, that's what i've done. points and timing have been done, but the carb will not adjust the car to where i want it. Also discovered a major problem was the the #1 plug wire boot had spark coming out and hitting the timing light clamp causing a loss of spark. moved it further up the wire and it helped with the variation of RPM, but i still cannot get the car to idle super smoothly under 950 while still running a good mixture. my process

-turn mixture screw 10 out, and 5 out for idle as a primary setting
- start car let it warm up
-tuen in the mixture screw until rpm drops, then turn out until highest rpm
-adjust idle screw to the idle i want....

after i do that last step, i can tell the car runs differently, like it's even more rich than it was before i dropped down the rpms. not sure if that helps but just some extra info. any carb procedure tips?

[mukluk]

Adjusting a two screw carb:
http://www.vw-resource.com/34pict3.html
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1960 Ragtop w/Semaphores "Inga"

[garyt]

I suggest clean and then lubricate inside the dizzy, especially the breaker plate as someone already said.

[sb001]

[mukluk]

[ashman40]