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Sun Sep 30, 2012 4:25 pm

i set the valves, timing, and all and tried to set the carb up according to the vw resource page.

http://www.vw-resource.com/34pict3.html

not having a tach i set the bypass screw (big one) as close to 900rpms as i could. i set the volume screw (small one) out 2 1/2 turns to start.

i never could really tell that the rpms dropped 25rpms when trying to fine tune the volume screw by turning it to the right. it seemed if i turned it left closer to 3 turns out the engine sorta started stumbling and if i turned it to the right which would be closer to 2 turns out it stumbled as well. i just left it at 2 1/2 turns out since that's where it seemed to run the best. if i slowly push the throttle in there is no hesitation but if i push it in quickly there is a tad bit of hesitation. this is probably since i have the german bosch made 009 dizzy (no clone). after the slight hesitation the engine accelerates smoothly with alot of power.

ok so i have the brosol 30/31pict carb on the 1600 single port engine. the jets in the carb are 120 main, 65 idle, 50 power, and a 125z air correction jet. i read on vw resource they suggest 125main and 55 idle when running vacuum advance dizzy. they say run 127.5 main when using 009 with the 30/31 carb.

the smaller main jet was for emissions and the larger idle jet was used to offset it. so basically if i put the 122.5main jet out of my other carb and ran it with the 65 idle jet is should be the same thing as running a 127.5 main with a 55 idle....or close to it???

right?

the carb on the car when i got it was the wrong one. it was a 28pict-1 with 122.5 main jet and 55 idle. wrong carb but it worked without hesitation with the 009 dizzy. the car ran good but lacked power due to the smaller carb.

i'm gonna save up to buy a 019 dizzy down the road that will work without any flat spot at all but until then i just have to deal with what i have. those 019 dizzys aren't cheap lol.

my engine is basically stock other than header exhaust.

what jetting do you guys run with brosol 30/31 pict carbs? does anyone have one on their 1600 single port?

please understand that a 34pict carb and a 1600 dual port engine require different jetting. they are pulling more air through compared to a signel port engine with a 30/31 pict carb.

the vw resource says running a 125main with a 55 idle is easier to tune and you get better performance than running a 120main with a 65 idle.

anyone else deal with this before? any suggestions? so if and when i get a 019 should i go back to a 120main or change it all out and go with a 125main and a 55 idle jet? all i would have to do is buy a 125main jet. i have all the others. the idle jet is a pain to get to though. i'd prolly have to remove the carb to get it changed out. you can't fit a socket onto it and you have no room to turn a wrench in there. so if running a 120 main and a 65 jet is as good or close enough to running a 125main with a 55 idle jet then i'm not gonna mess with taking it all off again.

i put the 122.5 main jet in today but i haven't cranked the car to see if it made any difference yet. i'll do that tomorrow maybe and see if it helps with the hesitation or not.

Mon Oct 01, 2012 9:43 am

I run a 30/31 on my 1600dp with svda, and use a 125 main and a 55 idle leave the 65 power in its place.

Mon Oct 01, 2012 1:37 pm

ok so which is which? i read on rob and dave's vw resource the angled jet is the idle and the one straight out is the power jet. i read on aircooled.net it's opposite. which is it?

rob and dave's:

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.

aircooled.net:

Solex, Brosol, or Bocar 34-3, or 30/31, use a 65 idle, and a 50 power jet (also called the "Pilot Jet). The Idle Jet and Power Jet are physically interchangable, but are different sizes. These are often switched on carbs by guys that think the idle jet should be small and the power jet should be big! Make sure the Power Jet (50, in the ANGLED location) is to the rear, and the Idle Jet (65, out the side) is in the front .

who is right?

mine is setup with the 65 jet angled and the 50 straight out. it has a 120 main jet.

Mon Oct 01, 2012 1:40 pm

I read the same thing when I did mine. The slant is power the straight in is idle.

Mon Oct 01, 2012 1:42 pm

so mine is backwards i guess. it must be terribly lean. i'll order a 125 main jet and put a 55 idle off of my other carb and leave the 65 power where it is.

Mon Oct 01, 2012 1:45 pm

That's what I run. 125 main 55 straight in, and 65 slant

Mon Oct 01, 2012 1:47 pm

well that's good i won't have to remove that slanted 65 jet that's impossible to get to. a socket doesn't fit on it since there's no room and there's no room to get a wrench in there lol. i didn't wanna have to remove the carb. i'll just replace the 50 with a 55 and put a 125 main jet in there. thanks for clearing this up for me.

i thought the hesitation was from the 009 dizzy. maybe it's because the idle jet is so lean. i'll change the jets out and see.

i could swap the 65 and 50 and leave the smaller 120 main but they say it's harder to tune the carb running it that way.

Mon Oct 01, 2012 3:49 pm

agreed. I've got mine set so it's just a little lean when cold, occasional cough just off idle, fine when warm.

you can get an open-end wrench in there..

the header exhaust will lean it out... you may ending up with +1 step for the jets.

jgrexx wrote: well that's good i won't have to remove that slanted 65 jet that's impossible to get to. a socket doesn't fit on it since there's no room and there's no room to get a wrench in there lol. i didn't wanna have to remove the carb. i'll just replace the 50 with a 55 and put a 125 main jet in there. thanks for clearing this up for me.

i thought the hesitation was from the 009 dizzy. maybe it's because the idle jet is so lean. i'll change the jets out and see.

i could swap the 65 and 50 and leave the smaller 120 main but they say it's harder to tune the carb running it that way.

Mon Oct 01, 2012 4:36 pm

well just for kicks i swapped the 65 and 50 jets around and i noticed no difference in performance. i'm not driving it just hitting the throttle in the garage. i ordered a 125main jet so i'll have to wait for that to come in. i'm thinking it's not gonna run right until i get a new dizzy. the hesitation is still there if i gas it quickly. if i just slightly move the lever it goes smooth with no hesitation.

i keep reading and everything is contradicting. some people say one jet is idle and others say the other one is.

DOES ANYONE KNOW WHAT JET IS TRUELY THE IDLE JET AND WHAT JET IS TRUELY THE POWER JET????

Mon Oct 01, 2012 5:30 pm

i'm thinking the angled jet is the idle jet.

when i ran the 120main jet and 65 angled jet with 50 jet straight the engine seemed to have alot more power. it ran really good.

when i put a 122.5main jet in there it seemed boggier like it was running rich and didn't have as much power.

it would seem the main and the angled jet were working together. if i were running a 122.5main and a 50idle it would be way lean and not boggy but a 122.5main with a 65 idle could be too rich for sure.

this is just an observation. still looking for a definate answer.

Ae0187 maybe you could swap your jets around and see what happens.

Mon Oct 01, 2012 9:34 pm

found this in another search:

Pilot (Idle) Jet

There is an pilot (idle) jet on all carburetors too - these are normally left at 55 for most carburetors (28, 30, H30/31 and 34 series), on any engine size (since it's only feeding the engine at small throttle settings anyway). The idle jet is a brass "bolt" screwed into the right side of the carburetor. On older/2 carburetors it has the idle solenoid screwed into the back of it. On the /3 and /4 carburetors - it looks like a bolt with a tiny silver plug in the center. On some models (the H30/31 for example) it is angled slightly towards the back of the car.

30 PICT and H30/31 Carburetor Jetting

On the H30/31, 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.

found here:

http://www.oocities.org/vwresource/jets

i'm going back to the setup that came on the carb since it seemed to work the best set like that. 120 main, 65 idle (angled), 50 power, 125z air correction jet. i'll try to tune it there first. this is closest to the stock setup for my 1600 single port engine anyways. originally it came with a 30 pict-3 carb with 112.5 main jet, 65 idle, and 45 power with 125z air correction. the brosol 30/31 pict is made closest to this carb and the 31 pict-3 carb that was in europe.

if it worked from the factory it will work now. the 30/31 pict is slightly larger than the 30 pict-3 carb. 25.5mm instead of 24mm. hence the slightly larger main jet and power jet. more air you need more fuel.

you can run 125 main jet and 55 idle jet that is suggested and they say run 65 power jet with that setup which i don't totally understand why they say that.....anyways that is not how they were set up stock. (30 pict-3)

i'm gonna try running it how it came set up and go from there. if need be i'll change it all out. i haven't noticed any pinging or popping or anything so it's not running lean.

has anyone bought a brand new brosol h30/31pict carb? if so what jets came in it and where were they located?

Tue Oct 02, 2012 5:33 am

When I bought my 30/31 brand new about 3months ago it came with a 50 straight in and a 65 slant, with a 120 main. I swapped the 120 for a 125 and the 50 for a 55, runs good. I'll swap them around when I get a chance to see how it runs probably will not be till Thursday though.

Tue Oct 02, 2012 10:55 am

well how yours came is how mine is setup. i found this from a guy in another thread. the 30/31pict brosol is a copy of the 31 pict-3 carb. the angeld jet is the idle jet and the straight jet is the power jet.

did you try running yours with the stock setup first? what made you change the jets out?

i cant' get mine to tune right. my heat risers are cut off and i have a 009 german dizzy which is wrong but should still work.

i can set the idle with the big screw but when i turn the small volume screw left or right from 2 1/2 turns out it doesn't really change anything. it is supposed to raise the idle and smooth it out and then you turn it in a bit to lower the idle about 25rpms and then go back and set the idle with the big screw.

what would cause this?

Tue Oct 02, 2012 3:07 pm

When I bought the car it had a old 30/31 on it that was crap, so I bought a new one as opposed to a 34-3 just because. I read that the 30/31 is for a sp and I have a dp, and for a dp you should rejet. I also had a 009 on it, but when I changed the carb out I added aircooled.net's svda. I can't tell you definitively if it was the jets or the dizzy that made it better, but its ALOT better than before. I couldn't stand that 009, I could never get it to idle right and that flat spot was so annoying.

Tue Oct 02, 2012 7:28 pm

yeah mine is single port so the 30/31 is the way to go. no use in putting a 34pict on it. i'm just gonna replace the 009 with a 019 or maybe the aircooled.net svda when i can afford to buy one. that should clear things up.

i was just hoping i could get it to run halfway decent so i could drive it until i get a new dizzy but i guess i'll just have to wait.

it's just weird since the 009 worked perfectly with no hesitation at all on the 28 pict-1 carb the PO had put on there. i knew there would be a difference i just didn't think it would be so much of a difference. i would think it would almost be undrivable the way it hesitates. it's crazy. i thought it would just be a slight hesitation but it's really bad. i guess you could drive it but you would have to barely accelerate so it wouldn't hesitate until you got the rpms up. now i understand why so many people hate the 009. i didn't understand before since i had no problems but now i understand.

using a 30/31 or 34 carb you might as well forget it running a 009.

it's weird because most dizzys for sale are the 009 and SVDA. neither work with the 30/31 pict carb. the only dizzy's that fit that carb are the 205T and the 019 which are very expensive and you have to buy them from someone that rebuilds them. they don't sale them online or at stores.

aircooled.net does sell the svda that works with the 30/31 which is the one you got. i think that is the only new dizzy that works with this carb that someone can buy. seems more people would make one that would work with it. they should remake the 019 dizzys or something and sale them new.

WTH does the 009 work on? only the smaller carbs like 30pict2 and smaller i guess.

Tue Oct 02, 2012 8:37 pm

I have no problems running an H30/31 and an 009, on a dual port no less. You need manifold heat for it to work.

Tue Oct 02, 2012 8:57 pm

i do plan on hooking that up but it's gonna require some work. you are saying if i hook that up the hesitation will go away completely?

what jetting are you running?

Wed Oct 03, 2012 7:07 am

jgrexx wrote: i do plan on hooking that up but it's gonna require some work. you are saying if i hook that up the hesitation will go away completely?

what jetting are you running?

Noone can guarantee your hesitation will go away completely since we have no idea how healthy the rest of your engine is. I just know the smaller carbs can be tuned to run well with the 009.

I have no idea what jetting it had. The carb was on an engine I pulled from a wreck. It looked new. I originally installed it and the 009 to break in a new 1600 rebuild and it ran so well I left it on and ran it for a couple years on my buggy.

Wed Oct 03, 2012 2:43 pm

hmm well something is wrong. i'm just not sure what it is. i'll have to figure it out i guess.