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Mon Jan 17, 2005 10:22 am

I have a rebuilt 34 PICT 3 and a rebuilt motor. It will start but it won't idle. I have set the big screw to 3 turns out (per book) and also tried 5 turns out (per old samba post). And set the small screw to 2 1/2 turns all the way to 5 turns out and I can't get the thing to idle. This carb worked on my motor before the rebuild. The book I have shows some kind of plate that goes between the intake gasket and the carb but I don't have this plate. It sounds like it's supposed to be plastic. I am aware of the problem with 009 advance and the 34 PICT 3 carbs but I have read that if you block the hole in the butterfly it will resolve this problem and I have done this. Any advice is welcome. Thanks,

Mon Jan 17, 2005 10:27 am

Not sure if you've already done all this but check out this post:
http://www.vw-resource.com/34pict3.html
It explains how you need to make some other adjustments before you get to the carb. Hopefully this will solve the problem.

Mon Jan 17, 2005 10:53 am

a thread currently running in the bus forum about this.

http://www.thesamba.com/vw/forum/viewtopic.php?t=98272

also lots of threads about the 34 pict and idle troubles if you search.

Mon Jan 17, 2005 11:21 am

Now, Im reading those links, but I've also been told theres a physical modification done to the Carb if you run an 009. Something about filling in a hole in a plate....? I'll see if its mentioned in those threads and articles, and if not I'll try to locate what the hell I'm thinking of.

Mon Jan 17, 2005 1:40 pm

I'm starting to wonder if this is an inherent problem in the 34-3 carb. I've worked on and worked on this car. It always kicks right off and runs beautifully down the road yet it never idles right and frequently dies in intersections. This is before and after engine rebuild, before and after carb tune-up, before and after converting from vaccum dist. to .009, before and after converting from points to electronic ignition, and after about ten million ways to re-adjust the carb. Maybe it's just a bad carb that can't be successfully rebuilt?
Tim

Mon Jan 17, 2005 1:59 pm

Well If not the 34-3 then what? I can't go to a smaller carb because I have port and polished my heads and I have a bigger than stock cam... not to big though. I was thinking about a weber progressive but I am up in the air about it. thanks,

Mon Jan 17, 2005 2:14 pm

I had a dream last nite that the rivet I put in my butterfly fell out.

Mon Jan 17, 2005 2:31 pm

vw66 wrote: I'm starting to wonder if this is an inherent problem in the 34-3 carb. I've worked on and worked on this car. It always kicks right off and runs beautifully down the road yet it never idles right and frequently dies in intersections. This is before and after engine rebuild, before and after carb tune-up, before and after converting from vaccum dist. to .009, before and after converting from points to electronic ignition, and after about ten million ways to re-adjust the carb. Maybe it's just a bad carb that can't be successfully rebuilt?
Tim

This can and does happen quite frequently... It's nice to have a second ( or even third) carb around to swap out... which I know is not a luxury alot of folks have. I happen to have that luxury and it's has helped to weed out a "dud" carb ( same with the 009 )

You have to finally come to grips at some point and decide whether to trash it, but youreally can't until you get another carb to see.

Mon Jan 17, 2005 4:44 pm

Thanks! I've gotten really close to getting an entirely new carb and seeing if it makes the difference.
Tim

Mon Jan 17, 2005 4:57 pm

http://www2.cip1.com/ProductDetails.asp?ProductCode=C24%2D113%2D129%2D031%2DK

If you decide to buy a carb, you might consider this one. It is better than the Brosal and is easier to fit if you have an alternator.

Have you checked the throttle shaft for wear. It is a common issue with older carbs. You will never get one to idle correctly if that is the porblem. You can have it re-bushed, but I would just buy the one I listed above.

Mon Jan 17, 2005 5:57 pm

What about a vacuum leak that is causing the problem? And if not the 34 PICT 3 then what carb should I go with.

Mon Jan 17, 2005 6:24 pm

thesponge wrote: What about a vacuum leak that is causing the problem? And if not the 34 PICT 3 then what carb should I go with.

If the throttle shaft is bad it's pretty easy to tell... grab both ends ( the throttle and the acclel linkage) and wiggle any slop at at all and it could be sucking air.

other than the intake boots cracked or torn and the manifold end castings being warped/not tight/ bad gaskets... there isn't any other places for the DP intake to leak.

another thing to try is to back out said "idle pilot jet" just a tad with the screwdriver right when the engine is coming off choke and about to begin to die. Sometimes the jet has been overtightend in the carb body and the jet seats too far in the hole in the carb body... if it picks up and runs faster with the jet barely turned out, then bingo! You have one of those.
If so, find the sweet spot and put a drop of blue loctite on the jet... re install it and set the sweet spot again. shut the engine off and let the locktite harden, then go about re-setting the carb mixture etc all over again.
(this is presuming you do not find a tiny piece of trash in the end of the pilot jet to begin with ( see the bus thread)

there is also a very small brass plug ( small flat blade screw driver to remove) next to the pilot jet... and there is a VERY tiny jet that lives inside that hole. It is commonly missed when someone cleans/soak/rebuilds the carb... you must make sure that it is not blocked either.

The 30/31 with the adaptor plate runs just about the same or at least as well as the 34 pict 3

Wed Jan 19, 2005 7:26 pm

Just as an update to all those that helped. My Bug is running and running really good. You probably want to know what the problem was.... I don't want to tell you! We forgot to tighten down the intake manifolds and we had a major vacuum leak. Thanks to all that provided me advice I really appreciated it.

Fri Jan 21, 2005 3:23 pm

Thanks TWD and Sponge,
The carb is original, so I'm going to just replace it, be easier like you say.
The link is much appreciated.
Tim