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Sat May 23, 2009 9:28 am

I'm working on my friend's '63 bug. It has a 1500 SP with a Brosol H30/31. It has been sitting for several years, although it ran well when he parked it last. It's been surprisingly difficult to get it running again.

It runs when you pour a thimbleful of gas down the vent, so I cleaned the carb (pulled the jets and cleaned them, pulled the carb top and cleaned the needle valve and checked the accelerator pump), and now fuel overflows the bowl and comes out the vent when I crank the starter long enough. it would probably start, but I haven't cranked it past the "fuel pouring out of the vent" stage. The needle valve moved freely and passed the "blow through the intake and gently depress the needle" test. I installed the float pin retainer above the float pin, with the curve towards the front of the car.

I'm very suspicious of the float sticking. It floats on the gasoline, but the brass hinge and pin sink. Is the brass "hinge" supposed to lock into the carburetor body anywhere? Mine just slides up and down and looks like it could easily get crooked and bind up. Is a sticky float a common problem? Thesamba search engine says no, but i'm running out of ideas.

Sat May 23, 2009 1:07 pm

hi. not familiar w/ Brosol H30/31. you write "Is the brass "hinge" supposed to lock into the carburetor body anywhere?" on solexes and solex/ bocars there is a place very close to the left edge of the bowl (inside, w/ the top removed) where there is a small slot on the front and back part of the left edge of the bowl at the top, right below where the gasket sits. The two ends of your float pin should rest in there. the pin will be secured when the top of the carb is replaced. Its like bridging from the 8 o'clock position to the 10 o'clock position. the in-between is free space where the float tab swings w/o interference. the pin and tab on the float shouldn't sink, unless brosal's are very different, in which case disregard all the above.

Sat May 23, 2009 2:55 pm

The pin just sits in there. It doesnt lock in. The little plastic retainer is what keeps it in. My guess is a bad needle and seat or your float is out of adjustment.

Sat May 23, 2009 3:13 pm

Thanks for the info, guys. Is it just me, or is this a terrible "design"? Why can't my friends all drive OG?

Do you know if I can pull apart the needle valve to check it and the seat, or do I just cross my fingers and buy a new one? Can I adjust the float if it doesn't shut off the fuel?

TIA

Sat May 23, 2009 10:26 pm

It's not a terrible design - it is a very proven design. There are no adjustments to the float. You should not try to bend the float or anything like that. There is a certain float level though, a factory setting more than an adjustment, and that is set up by the thickness of the gasket(s) under the needle valve.

-Andy

Sun May 24, 2009 5:59 am

Thanks Andy, that gives me hope. I thought I had read somewhere that on some carburetors the fuel level in the bowl could be measured and brought to spec. by adjusting the thickness of the gasket(s) under the needle valve. That's what I thought Michael meant. Maybe I'll check my fuel pressure and then look to my needle valve. Thanks for the help!

Sun May 24, 2009 9:37 am

Oh, by the way, I remembered a post from Keith a few months ago about H30 floats, I'll quote him here:

keifernet wrote:
Most H 30/31's have the solid black float that Wildthings speaks of. They can deteriorate and or soak up fuel and become "HEAVY" and this is your problem. The hollow plastic real Solex style floats can get a pin hole and take on fuel but on these it's an easy thing to spot. Not so with those solid one.

You need to get a hold of a new or good used float and see. Also you can weigh your float... should be like 10.5 grams * I'd have to look that up.

ALSO the 30/31 takes both washers out of the rebuild kit or a single thick washer ( the original washer is thick & brass/gold colored) Using to thin a washer under the needle valve on the H 30/31 ( 30 pict 3 is the only other carb that needs the thick washer setting) can cause flooding you speak of. Or you have a combination of these factors.

Sun May 24, 2009 2:41 pm

autobhahn wrote: Thanks Andy, that gives me hope. I thought I had read somewhere that on some carburetors the fuel level in the bowl could be measured and brought to spec. by adjusting the thickness of the gasket(s) under the needle valve. That's what I thought Michael meant. Maybe I'll check my fuel pressure and then look to my needle valve. Thanks for the help!

Actually Im just used to 30 pict 1s. You can adjust those floats. Ive rebuilt enough carbs I should know that you cant adjust a square float.

shim thicknesses under the needle and seat:

28 pict 1.0mm
30 pict 1.0mm
30pict2 1.0mm
30pict3 1.5mm
34pict3 .5mm

30/31 1.5mm

Sun Jun 07, 2009 6:02 pm

I wish I could spend all my time on air-cooled VWs, but unfortunately, it's a spare time thing. so sorry for the delay.

Thanks for the info, though, it was extremely helpful. I replaced the needle valve and verified the shim, no change. weighed the float, it was about 10.5 grams.

So I scrounged around and found an OG Solex 30PICT2 in the parts pile, this one off a '69 autostick bug. Hollow plastic float, as you know. But the hinge pin was much longer and nestled in those slots that the pin retainer slides into.

You see, my Brosol hinge pin is so short that it doesn't catch in those slots. It allows the brass hinge part to drop to the bottom of the bowl, even when the bowl is full of gas and the black part floats. Is this normal? As you may have guessed, I can't find a replacement Brosol float anywhere.

So my question now is: Can I just put this hollow rectangular Solex float into my Brosol H30/31PICT? I know a rebuilt German carburetor would be better, but the Brosol is tuned for this engine, clean, low mileage, on site, paid for, etc....

And if I can change out the floats, how thick would the needle valve shim need to be?

Thanks again!
Ben

Sun Jun 07, 2009 7:03 pm

autobhahn wrote: I wish I could spend all my time on air-cooled VWs, but unfortunately, it's a spare time thing. so sorry for the delay.

Thanks for the info, though, it was extremely helpful. I replaced the needle valve and verified the shim, no change. weighed the float, it was about 10.5 grams.

So I scrounged around and found an OG Solex 30PICT2 in the parts pile, this one off a '69 autostick bug. Hollow plastic float, as you know. But the hinge pin was much longer and nestled in those slots that the pin retainer slides into.

You see, my Brosol hinge pin is so short that it doesn't catch in those slots. It allows the brass hinge part to drop to the bottom of the bowl, even when the bowl is full of gas and the black part floats. Is this normal? As you may have guessed, I can't find a replacement Brosol float anywhere.

So my question now is: Can I just put this hollow rectangular Solex float into my Brosol H30/31PICT? I know a rebuilt German carburetor would be better, but the Brosol is tuned for this engine, clean, low mileage, on site, paid for, etc....

And if I can change out the floats, how thick would the needle valve shim need to be?

Thanks again!
Ben

Yes you can. Use a single thick shim or the two shims in the kits that add up to .060" or 1.5 mm

Sounds like your float is missing or maybe the pin went missing and someone tried to make a home made one? :?