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Sat Apr 18, 2015 10:29 am

I have a 75 Bay however a Type 1 conversion was done to it. The bus starts very quickly and idles well, Its O.K. through low RPM's, but as you start to spin it up it loses power. Even if you are just idling and give it gas, it seems to take too long to wind up. I feel like the vacuum advance is not working properly.

I have attached a picture of the current plumbing.

My first question is should I block off port B. It seems to serve no purpose other than to allow dirt in.

Nextly, which port should the vacuum advance be connected to? It's currently labeled as A.

Thanks in advance!

Sat Apr 18, 2015 10:34 am

I'm pretty sure you block a c and d, and then use the one that's on the left side of the carb for the advance. If you're using a single vacuum can. B should vent to your oil filler.

Sat Apr 18, 2015 11:06 am

My mistake, B was already hooked up to the oil filler. I pulled it for the pic. Doh. I made the changes and no difference.

At least now that I know this is correct, I can start troubleshooting the carb.

Sat Apr 18, 2015 11:12 am

Found this in the "Samba" Photo Gallery doing a search for "PICT-34".

Sat Apr 18, 2015 11:36 am

A picture of your distributor and the part number off of it would be helpful.

What do you have your timing set at and how did you go about setting it? Lots of ways to do it wrong, including doing it by the book if not every part is working just like it did when it left the factory.

Sat Apr 18, 2015 11:55 am

Your h30/31 pict carb will only work well with an SVSA distributor or mechanical advance style; it pulls too much vacuum under load for an SVDA setup. The photograph is for a 34pict3.

Sat Apr 18, 2015 7:11 pm

Here is a shot of the distributor. Can't get the part number right now but will try to find it in the a.m.

Thanks

Sat Apr 18, 2015 7:17 pm

That is a SVDA distributor, which is not a perfect match for a 34PICT3 carb which is what most double port engines have. If setting your timing at idle you would want to set it at 7.5° BTDC at base idle with the hose off. Better still to set is at 28°BTDC @3500+ rpm, hose off and plugged.

There are simple modifications you can make to a 34PICT3 carb to make it work better with a SVDA distributor.

Sat Apr 18, 2015 7:19 pm

But I think the OP has an h30/31pict carb, which really isn't made to work with an SVDA at all. It even has the adapter plate to mate the small carb throat with the large throat dual port center manifold.

Sat Apr 18, 2015 7:23 pm

From here it looks like an 043 style unit (who knows where it's made), as Asiab3 says no bueno with a H30/31, it's a pretty good distributor, it's just that your carb doesn't speak the same language it does, a 34PICT3 carb would be a better option for that application.

Sat Apr 18, 2015 7:30 pm

You can see the adapter at the base of the carb for the h30 to 34 manifold

Sun Apr 19, 2015 4:30 pm

So I found a local guy who lives and breaths air cooled VW. He is coming out on Tuesday to tune the bus for me. Based on the feedback here however, it sounds like the wrong carb may be in place. If I go out and source a 34Pict3, does anyone have recommendations on where to purchase? CIP1 seems to believe they are selling the highest quality available and that many are cheaply built Asian copies.

Too bad on this one, the PO just put this carb on before selling. Looks like he pict the wrong. < dumbest joke ever right there

Sun Apr 19, 2015 4:46 pm

Stonedbeetle wrote: If I go out and source a 34Pict3, does anyone have recommendations on where to purchase?

http://www.thesamba.com/vw/classifieds/detail.php?id=1546867

Sun Apr 19, 2015 5:52 pm

Thanks . . . . I shot a note to Tim.

Sun Apr 19, 2015 6:15 pm

Stonedbeetle wrote: Thanks . . . . I shot a note to Tim.

I have a 30/31 Solex/Brosol carb and a SVDA dizzy on my T181. Nice combo, easy to tune, runs smooth, and has just as much power as the more finicky 34pict3.

Sun Apr 19, 2015 7:49 pm

Question for the group: the carb base adapter the OP has also shifts the carb to the left a little bit... which may be important since it looks like the generator has been replaced with an alternator.

Any concerns, fitment-wise, with a OEM 34PICT and an alternator? I have an alternator conversion on my 70 but running a smaller 30PICT *and* my off-shore alternator has a divot in the body for carb clearance, specifically to clear the accelerator pump linkage. Even so I had to modify the mounting strap a bit.

I suppose you could look for the same divot on your alternator, OP.

Or, I may be worried about nothing. :) :)

Sun Apr 19, 2015 7:53 pm

Vince Waldon wrote: Question for the group: the carb base adapter the OP has also shifts the carb to the left a little bit... which may be important since it looks like the generator has been replaced with an alternator.

Any concerns, fitment-wise, with a OEM 34PICT and an alternator? I have an alternator conversion on my 70 but running a smaller 30PICT *and* my off-shore alternator has a divot in the body for carb clearance, specifically to clear the accelerator pump linkage. Even so I had to modify the mounting strap a bit.

I suppose you could look for the same divot on your alternator, OP.

PM or email Tim@Volkzbitz and ask what he does for making the 34pict3's fit with alternators. There are also a few different styles of alternators on T1s, (internally or externally regulated, for example.) I know I mentioned it to him on the phone when I ordered one years ago, and it was never an issue fitting it next to the Euromax Wonder Alternator. There was a rumor going around for a while saying you could flip a linkage over, but I DON'T think it's true. I DO think there is a modification Tim makes though, though I don't know much about it.

If your '70 is a single port, remember that 99% of the dual port manifolds fit the 34 series carbs, and 100% of the single port manifolds fit the 30 series carbs. That's also what the adapter does.

Sun Apr 19, 2015 9:13 pm

Thanks for the extra info. In my case I took a quick crack at reconfiguring the carb linkage but opted for modding the bracket instead... I couldn't see how reversing it would help... since it was the pump arm itself that was rubbing.

Mostly just don't want the OP to pin his hopes on a different carb, only to find it won't fit due to the alternator.

Sun Apr 19, 2015 9:36 pm

Vince Waldon wrote: Thanks for the extra info. In my case I took a quick crack at reconfiguring the carb linkage but opted for modding the bracket instead... I couldn't see how reversing it would help... since it was the pump arm itself that was rubbing.

Mostly just don't want the OP to pin his hopes on a different carb, only to find it won't fit due to the alternator.

I don't actually think reversing it works. I've only heard it as a rumor; I believe more is involved than that. But I do know Tim makes it work somehow. Unfortunately, I only have his carbs here; I don't have any carbs he hasn't worked on!

There are metal spacers that don't change hole alignment, meant to help a carb clear an alternator. The ones that do change hole spacing help it clear as a defacto design choice.

Mon Apr 20, 2015 12:27 am

Viewing the pic of the distributor, why are we seeing pushrod tubes? Have you removed the rear breastplate tin and just not replaced it?? Also the lower rear tin plate diverters?? Do you have the aftermarket Type 1 engine to Type 4 conversion surround in the engine bay?? You can't put a Type 1 Early Bay engine into a Late Bay Type 4 engine body without it. Do the search on what's entailed