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Sun Feb 12, 2012 7:44 am

Can anyone point me toward one or more suppliers that sell carburetor jets for the Brosul/Solex H30/31 carb? I have put a new one on my 71 Bus and the main is a 120 and it's too lean. I prefer not to open up the existing jet, but instead to try a couple of replacements. A kit of jets would be nice. I think probably a 127.5 or 130 might be a good starting place. Thanks.

Sun Feb 12, 2012 8:16 am

I think these will work? Call to be sure..

http://www.aircooled.net/new-bin/viewproductdetail.php?keyword2=FSK0043&cartid=

Sun Feb 12, 2012 8:47 am

Hi if I remember right, the jets were the same in the pict 34s. Here are some links on the subject. Hope this helps! Good Luck
http://www.vw-resource.com/carb.html#brosol
http://www.vw-resource.com/jets.html#30

Sun Feb 12, 2012 8:59 am

On this subject, can anyone tell me why this carb has 2 idle jets?

Sun Feb 12, 2012 9:05 am

I am not sure how close to OK city you are. Bethany Imports is OKC. And in my search I have visited motor cycle shops. Some Japanese bikes with carbs. are running similar jets. Try and talk to the mechanics and not the parts geek at the counter. Good luck.

Sun Feb 12, 2012 12:03 pm

Mr. Unpopular wrote: On this subject, can anyone tell me why this carb has 2 idle jets?

Yes!

http://www.vw-resource.com/jets.html

Sun Feb 12, 2012 3:11 pm

Thanks for all the input. Bethany didn't have the sizes I wanted, but opened the jet up to 130. I'll look at aircooled and other places online. Maybe find a cheap used 34pict and check the jets. Thanks again.

Sun Feb 12, 2012 4:22 pm

Mr. Unpopular wrote: On this subject, can anyone tell me why this carb has 2 idle jets?
Found this in the link.
On the H30/31 carburetor, there are two brass jets on the right side (right is right of car). The angled one (points slightly towards the rear of the car) is the idle jet. The other one (pointing straight out to the right side of the car) is the power jet, which feeds additional fuel at high throttle/high rpm. The power jet is needed to correct a tendency for the air correction jet to work TOO well at max airflow - it leans the mixture off too much and the power jet corrects this.

Wed Aug 12, 2015 2:22 pm

Tcash wrote: Mr. Unpopular wrote: On this subject, can anyone tell me why this carb has 2 idle jets?
Found this in the link.
On the H30/31 carburetor, there are two brass jets on the right side (right is right of car). The angled one (points slightly towards the rear of the car) is the idle jet. The other one (pointing straight out to the right side of the car) is the power jet, which feeds additional fuel at high throttle/high rpm. The power jet is needed to correct a tendency for the air correction jet to work TOO well at max airflow - it leans the mixture off too much and the power jet corrects this.

This information is incorrect. The idle jet is towards the front of the vehicle, and the Power jet is towards the back of the car. Rob and Dave's site is wrong, and has been the source of quite a few threads regarding which jet is what.

Edited for jet names

Wed Aug 12, 2015 3:59 pm

scrivyscriv wrote: The idle jet is towards the front of the vehicle, and the air correction jet is towards the back ...

Sigh. Well, no, not quite, but thanks for reminding everyone of the bogus info from that source. It's quite amazing how much time and space on thesamba is/has been devoted
to straightening out the misinformation coming from those guys.

Here's the straight skinny: http://www.thesamba.com/vw/forum/viewtopic.php?p=6927166

Wed Aug 12, 2015 5:47 pm

Ok what am I missing here. The positions seem correct. Is it the nomenclature confusing the issue?

glutamodo says that
#3 is the Idle jet (pilot jet)
#0 is the Aux jet (power jet)

#3 (angled one (points slightly towards the rear of the car) is the idle jet.

#0 (pointing straight out to the right side of the car) is the power jet

glutamodo wrote: On the H30/31 the auxiliary fuel jet is the 50, the idle fuel jet is the 65.

The power fuel jets are in the top half of the carb.

Thank You
Tcash

Wed Aug 12, 2015 6:47 pm

Someone incorrectly translated the German on that article. I don't even know what a 31-pict 3 is either, it's not an H30/31, and it's not in my Green Bentley. We are talking about a Baywindow, right?

Item 9 air correction jet
Item 17 main jet
Item 34 pilot jet

The table lists the following:
Air correction jet 60Z
Main jet x125
Pilot jet g57.5

Compared to the pic in question, the jet sizes are all slightly larger, but clearly establishes what jet each size can be reasonably expected to represent.
I wish the Bentley had been more specific but of course we are all aware of how it can be vague on some topics.

Wed Aug 12, 2015 7:39 pm

31PICT-3 and 34PICT-3 are 2 completely different units, the 31 came on Euro delivered 1300 Beetles and the 34 was used on dual port 1600's.
But Andy's diagram shows the similar jet layout to the 30PICT-3 bus carb just fine. But what perplexes me is when an idle cutoff is used why is it screwed into the one labelled "auxilliary fuel" when it would be more useful in the idle circuit. If it only comes into play at full throttle why does it need a cutoff, and why would the supposed "idle" one not need a cutoff?
Gotta find a junk carb and saw it up to see just where those passages go.

Wed Aug 12, 2015 7:52 pm

After dicking around with an H30/31 for a year, I proceeded to dick around with a 34pict3 for two years. Now I'm on the 30pict3 train, and I think I'll stick with it for a while. That being said, they are all COMPLETELY different plumbing-wise. It's not apparent by looking at the plumbing, but tracing the passages with fluid and making flagrant LM-1-based jet swaps (like 45 to 70 pilot) tell us a lot about how they're all so different. The diagrams are useful for numbers and locations, but we have to be careful not to take labels off other carb photos. For example, glutamodo posted a picture of the 31pict3, then described it as an H30/31, even though some variants of those carbs are different. This confuses things…

So…
Busdaddy, what carb is that picture of? The pilot jet on all my 30pict3s are like in your picture. The power jet is non-adjustable. [Colin went through it years ago and ended up drilling out the passage (or nozzles?) to experiment.] The solenoid shown is for the idle circuit as well. This is where the H30/31 differs, in that the power fuel flow is allegedly adjustable. The H30/31 has the cutoff on the left like a 34pict3. So now I'm confused because of all the diagrams and labels. :D

Robbie

Wed Aug 12, 2015 7:59 pm

asiab3 wrote: So…
Busdaddy, what carb is that picture of?
I pilfered it from the gallery, Dana Champion posted it and says it's 30PICT-1 and -3. The carb in the pic says 30PICT-3 on the side.

Wed Aug 12, 2015 8:23 pm

So basically what we were all getting at is a definitive answer on WHICH PORT on the H30/31 is for the actual idle jet. I can guarantee rob and dave's site has a crapload of bug owners jetting their carbs incorrectly!

Anyone here have some mfr literature on the carb, with a breakdown?

Wed Aug 12, 2015 8:28 pm

scrivyscriv wrote: So basically what we were all getting at is a definitive answer on WHICH PORT on the H30/31 is for the actual idle jet. I can guarantee rob and dave's site has a crapload of bug owners jetting their carbs incorrectly!

Anyone here have some mfr literature on the carb, with a breakdown?

Glutamodo, who knows more about carbs than probably anyone else on here, says the H30/31 copies it's idle circuitry from the non-USA 31pict3. The picture below is of the 31pict3, which should be identical to the H30/31. That means that the diagonal rear jet is the idle/pilot jet, and the (0) jet is the "power" auxiliary fuel jet. (30pict3 and 34pict3 do not have this jet as a serviceable item, as far as I know.)

The photo is from VW technical bulletin K-40 from April 1971, and Glutamodo did the translations himself.

Robbie

Wed Aug 12, 2015 8:45 pm

What's making me question that is the jet sizes, they don't look right for the jets they are supposed to be.

Edit, I'm not a carb guy by any stretch, I am just looking for solid answers to this. The site is filled with threads that have contradicting information about it!

Wed Aug 12, 2015 8:45 pm

scrivyscriv wrote: What's making me question that is the jet sizes, they don't look right for the jets they are supposed to be.

Size is relative to pressure and volume required. What doesn't make sense?

Wed Aug 12, 2015 8:50 pm

It may be the differing terminology. When I see a 145 jet, that doesn't seem "main jet" size to me, just way too big. I don't have any books on the carb glutamodo is referring to but I wish I did, would be very helpful to be able to compare numbers to the 34 pict 3.