Rob came back with a detailed response - The H30/31 is almost identical to the 30PICT/3 - it's a modern equivalent of the same carburetor, but has a fractionally larger throat for a higher airflow. I have 4-5 I've collected over the years, and the smaller ones can be re-drilled to the larger sizes. But engines do differ a little, and the sizes above are "ball park" figures rather than definitive. The main jet provides fuel from about 1500 rpm right up to maximum rpm. When using the 30PICT or H30/31 carburetor on a twin port manifold and any vacuum distributor, change the jets to X125 or X127.5 main, 55 idle, and leave the air correction at 125Z. If the engine is stumbling at 2000 RPMs and lower, then you need to richen up your idle jet (go to a larger size) - but check carefully for air leaks around the throttle shaft first!. If you do not hear this clicking sound, it's time to replace the idle cut-off valve. FAQs Ask a Question. The air correction jet affects mostly the high rpm -- not much effect on low-middle rpm). My distributor is a vacuum advance (with a centrifugal?). The angled one (points slightly towards the rear of the car) is the idle jet. FREE Shipping. Take the car for a run at a modest speed - say 35-40mph. View Profile View Forum Posts Private Message View Blog Entries Member Join Date Aug 24th, 2004 Location Anaheim,CA Posts 3,345. The larger 34PICT carburetor should have the larger X127.5 main jet, and since the larger 34PICT carburetor doesn't have the extreme airflow with a 1600cc DP engine that the 30PICT carburetor does, the over-rich problem is reduced, so you use a SMALLER air correction jet - less correction is needed. Thanks Sent from my SM-G930F using Tapatalk low_light_craig, Jun 9, 2017 #1. snotty. $9.81 $ 9. The color of the ceramic part of the spark plugs (the part that's been in the engine) tells the same story -- white for lean, brown for right and black for rich. It's actually much easier to do if you remove the top of the carburetor and the float. With lean jetting you are likely to need more throttle and have slightly worse fuel economy - using the slightly richer settings I'd suggested above will give you a little more power and a cooler running engine, so hopefully fuel economy will improve a little, but don't expect too much - fuel economy with the heavy Type 2 body is never very good. OK Here is a picture looking at the left side of the carb. Posted by 3 years ago. The engine runs fantastic (when I'm not having ignition related issues), and I just had the spark plugs out yesterday. Another question - The car runs terrible but it runs. Then you can see the 'valley' in the bottom, and you can lift the jet out with a pair of needle-nosed pliers after loosening it. If it is any lower the choke may be staying on too long, or it may be stuck on and won't open at all. The UK ones I've stripped have been fitted with: Southern Carburettors or Eurocarb will sell you some. The proposed problem deals with the Main Jet of the carburetor. The idle cut-off valve is not strictly a "jet," but this is a good place to discuss it. They are cheap enough. Starts right up and runs great. Rob's note regarding modern fuels: There are two major issues with modern fuels. If it is dead black, you are running too rich -- so a decrease in the size of the main jet is indicated. It this case you would definitely need to reduce the main jet size to say the size 122.5 or the 120. I've been running my '68 Bug with the X127.5 main jet in the smaller carburetor, and he's running a tad rich. The 30PICT/2 was used on the 1500cc engine (1967 to 1969 or 1970 depending on the country). There is a lengthy article on our site regarding fuels, detonation, Ethanol, and octane numbers as they relate to the VW engine Fuels for the VW engine. Dave bought a Pierburg model 34PICT/3 carburetor from Aircooled.Net, and none of the jets had the sizes stamped on them. If you have a significantly larger idle jet (e.g., 70 or so), John Connolly recommends going down until you can not get a good engine response with the mixture screws anymore. I have lowered the fuel pressure down to 2.5 psi and checked the float bowl fuel height. Replacing the main jet in is super easy -- just put it in the hole in the side of the carburetor, then put the screw driver in after it and slide it along the 'valley' that runs across the bottom of the float bowl. I can't remember off-hand which is which, but the power jet is in a vertical protrusion on the side of the carburetor which leads up to the outlet for the power jet in the top of the carburetor...the other one is the idle jet. The effect is not linear though, so as the airspeed increases, the main jet will start to deliver a richer mixture (too much fuel), so the air correction jet is needed to add air and stop the mixture going over-rich, then the air correction jet starts working too well at higher airflows (engine revs) so the Power Jet (Aux jet) is need to add more fuel again. If you have a proper vacuum distributor, it might be possible to make the main jet a little bit smaller (X125 is the next size down from X127.5), but this will not make very much difference in the fuel consumption. 5.0 out of 5 stars 6. It's possible to develop partial blockage in one or more jets. Which one is which one? Solex 34 pict 3 jet size. And of course make sure that it's properly connected electrically to the connection on the coil where power is provided (the + connection) -- the lead can break off. 34 PICT 3 Idle Jet; 34 PICT 4 Idle Jet; Jet Size G55. With a leaner 140Z air correction jet in the carburetor) I got 11.6 km/l (27.5mpg US). Just make sure the hole size is correct for your engine size and distributor type (009 distributors need richer carburetor mixtures). Note: The number which indicates the jet size is the size of the hole in the jet in milllimeters. Try the X125 main before you try the X127.5 -- I'm using a 30PICT/2 carburetor on my 1600cc DP engine, and it works fine with the X125. The idle jet is usually a size 55 (when the main jet is normally a size X125 or X127.5) but it might be a size 65 if the main jet is a X122.5 or smaller. Luckily I looked at the main jet in the 34 Pict 3 and it was a 127.5. That's considered by some to be borderline and can cause the engine to run just a smidgen warm due to less evaporative cooling. Revving the engine in neutral will result in hanging RPM’s, or RPM’s will slowly drop back to idle RPM. Have a look at the size stamped on it too. The 34PICT normally has a X127.5 main and a 140Z or 170 air correction jet. Originally Posted by wifesbug. So with a vacuum distributor, using a 55 idle, X130 or X132.5 main and about a 100 - 120Z air correction jet should provide good mixture for a 1776, without affecting fuel economy to badly (fuel consumption WILL be a little higher with the larger capacity though). Sounds like a good starting point! Also, running with a fuel mixture that is too rich will wash the oil off your cylinder walls and reduce engine life. Dave has done so with good success. Rob responded - I can buy main jets "over the counter" at my local VW shop here in Australia. The speed of the engine (RPM) when it's doing this tells you which jet you need to change. Use a steady throttle - minimum acceleration. Dave jetted his new carburetor as follows: main jet - X130; idle jet - 55; air correction jet - 80Z. Hey, use the stock jet size, which is 125 for the 34 PICT-3. If it seems a little rich at higher speeds (plugs sooty after a plug read) then try the 130Z air correction jet. Overview. Some of the replacement carburetors (H30/31 and 30PICT/3 maybe???) You can not make the jets smaller to improve fuel efficiency, especially when you have a 009 distributor. 34 PICT Carburetor Combination, Automatic Choke Discussion and Adjustment Procedure. The air correction jet starts leaning the mixture to bring it back into balance, but as the rpms (airflow) rises to near the maximum for that carburettor, the air correction jet works too well, running the engine lean. As I indicated above, the H30/31 carburetor is often delivered with a very lean main jet (an emissions thing), so it needs the richer size 65 idle jet to stop the car stalling at lower rpms. You also set the accelerator pump for maximum stroke when using the 009. At the beginning I started to use a Solex 30 PICT-2. E10 usually needs a larger main jet and might also need a larger idle jet. I live just about sea level here in Louisiana. The 30/31 is a slightly different carb, so your numbers may vary. The standard jetting that the 30PICT/1 & 2 carburetors came with is size X122.5 or X125 main, size 55 idle, and size 125Z air correction jets. Ethanol contains USED oxygen which canoot be burnt again, so adding ethanol to gasoline/petrol, reduces the amount of energy per litre/gallon. There is also a 65 power jet there too) a X127.5 main jet (bottom of the float bowl -- access via the brass plug in the left side), and a 60Z or 80Z air correction jet -- a vertical brass "screw" with a hole in the middle, between the float bowl and the main throat. For the 1600cc engine, you need more fuel flow, so a larger X127.5 main jet and 100Z or 120Z air correction jet are needed. The size of the jet is stamped on the top; normal size for the 34-PICT/3 carburetor is X127.5 (1.275mm diameter hole). If the idle cut-off valve fails in the shut position, the car will still run (roughly) on the main jets but will stall as soon as you take your foot off the throttle. Regarding the 1776cc engine: the stock 34PICT/3 carburetor with a fractionally larger main jet and a fractionally smaller air correction jet to suit the higher air flow being asked of the carburetor should suit nicely. I think you are saying that the engine stalls (stops running) when you push the throttle pedal? JET KITS are available if needed. Now I have installed a newer Solex Brosol 30/31 carburetor (the Brazilian one), in good shape. The center electrode should look quite clean and grey/white. Solex 34 PICT Carb Spacer, 3/8" Thick (6mm), Fits 34-3 and 34-4 Carburetors, 00-9705-0 is used to move the carburetor up for the accelerator pump linkage to clear the larger diameter alternator when doing an alternator conversion with the generator carb. Remove the main jet (as above) and blow through it (check for crud in the float bowl at the same time). Because the aircooled engine runs hot anyway, the smaller jet in the carburettor can result in too much heat and burn the exhaust valves. $10.84 $ 10. There is enough variation in fuel types, wear and tear on engine and carburetor, altitude and so on that you might need to experiment a little. 84. Brosol/Solex Idle Jets .65, Compatible with Dune Buggy $9.52. The Brosal 34 PICT-3 carburetor was built for use with a standard generator, and when used with an alternator (fatter diameter), the accelerator pump linkage will hit the body of the alternator. To summarize: idle jets operate from idle to 2500-3000rpms or so. This is not correct. 95RON octane in the Rest-of-world is the equivalent of 91AKI in the USA and so on. Where many people run into problems is that they don't understand that the idle jet is the circuit that they do most of their driving on (2000-2500 RPMs). You can find 57s, etc. It's a complex problem that faces ALL open throat style carburettors. The 137.5Z air correction jet is too big -- it's letting in too much air. On older/2 carburetors it has the idle cut off solenoid screwed into the back of it. If the jets are screw in to tight that will cause high idle. The 30PICT/2 carburetor has a fuel idle cut-off in the right side of the carburetor but the 30PICT/3 and the H30/31 should have an air idle cut-off in the left side for the carburetor (same as the larger 34PICT/3) -- that was part of the change to the /3 carburetor version -- moving the idle cutoff valve to the left side. Rob responded - If you still have a vacuum distributor - yes. An altitude of 5000 feet is roughly equivalent to a one size main jet difference. The air corrections I have are 125z, 170z and in the carburetor a 135z. Volume: 1700000mm 3. The numbers are: 231 168 015, and 043 905 205 L in the second line. The 1600cc DP can flow more air than the 1600cc SP and smaller engines. *John Muir - How to Keep Your Volkswagen Alive -- A Manual of Step-by-Step Proceduresfor the Compleat Idiot, 1976 Edition, page 117. 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). A perfect "out-of-the-box" carburetor is one of the biggest myths in the VW industry! I don't think you'd honestly notice the difference. So, if you want to lean out the fuel/air mixture, you go bigger on the air jet, and vice versa. Unscrew this bolt and look at it -- if there is a jet screwed into the bolt (older models), you can deal with it in hand, so to speak. I've verified that the vacuum advance and vacuum retard on the distributor are working. It only works at full throttle and high RPMs ? For a 1776cc engine with 009 distributor, 55 idle, X132.5 or X135 main, and air correct around 80Z should be close to the mark. Running a 130 main jet. When using the 30PICT on a twin port manifold and any vacuum distributor, change the jets to 55 idle, X125 or X127.5 main and leave the air correction at 125Z. Manufacturer: Classic. Main jet = 132.5. Normally, for stock daily-driver Bugs, you will find that an idle jet size of 55-60 is right for you. Carburetor model numbers can usually be seen stamped on the side of fuel bowl. The only method of getting it exact is to run the car on a dynomometer with an exhaust gas analyser in the exhaust pipe. This item: VW Bug Carburetor 34PICT 60/130 Jets fits: Bug Bus Ghia 34 PICT-3 CARBURETOR MAIN AND IDLE Jets $12.95. I'd go for a 130 main. If the fuel/air mixture is too lean, the engine will run very hot, stumble, and misfire -- and burnt valves can be the result. You must do the opposite -- make the main jet a little bigger (X130 or X132.5) to stop the engine from hesitating when you accelerate. 81. If it still seems hot, go to 127.5. Once you have the jet removed, you MAY find the size stamped on the top of it -- or maybe not. Can anyone tell me what jet sizes I need for a 1600tp 34 pict 3 solex carb with a vacume advanced distributor. With the larger main jet, you might also need to consider a size 50 idle jet in lieu of the normal 55. Idle problems on stock engine, 34 PICT carb, 009, 1 5/8" exhaust. Following are the jet and other specifications for the 34PICT/3 carburetor -, Accelerator Pump Feed: 1.3 - 1.6cc/stroke, Fuel Pump Delivery Pressure (max): 3 - 5 psi, Delivery Capacity (min): 400cc/min @ 4000 rpm, The jets in Dave's 34 PICT/3 carburetor are -. Jetting With the Centrifugal-Advance (009) Distributor, Tuning the 009 Distributor/ The effect is clearly noticeable from 3000 RPM upwards (just under 60 mph), and probably a little lower than that. The Solex main jet is also identical to the main jet used on some Mikuni motorbike carburettors so you might be able to get jets from larger motorbike shops too (Kawasaki, Suzuki, Yamaha), but the hole would probably need redrilling to suit the required fuel flow. If you have a 009 distributor (no vacuum canister on the side), the main jet should be about X130 or X132.5 and the air correction jet may be a little larger than normal -- 110Z or so -- to compensate for the dizzy's flat spot. Thus a size 55 idle jet is 0.55mm, size 125 is 1.25mm, etc. You can buy different size jets for the 30/31 carb but you may want to put it together and see how it runs first. Carburettor jets Solex - Weber. So how do you know which to use? The back one (pilot?) Idle jet = 65. As indicated previously, the VW engine actually runs better at fractionally rich settings (ideally 13.8:1 rather than 14.5:1 according to Bob Hoover who did lots of testing), but they are usually jetted a little leaner than that, so the X127.5 is really a minimum jetting for the 1600cc engine. The air correction jet has to be the right size for the same reason. In these later models, you can easily change the jet with a medium screwdriver either with the top of the carburetor removed or with the carburetor completely off the car. (See our Automatic Choke Discussion and Adjustment Procedure.). For example, a 40 IDF would need a 40 x 1.25 = 50 idle jet. It should not need to be bigger than that with a vacuum distributor (009 distributors need richer mixtures). This will tell you if it's running rich or lean at speed and then you can set the air correction jet accordingly (smaller air correction means richer mixture - is delivers air so it works the opposite to a main jet. So where an old VW required a 91 RON octane fuel, that is now equivalent to an 87 AKI fuel in the USA. So I replaced it with a 30 PICT-3 carburetor in a good condition. Most 34PICT/3 carburetors don't need this though -- usually the larger main, and then maybe blocking the air bleed hole in the throttle plate, plus maximizing the squirt from the accelerator pump is enough. Solenoid, and he 's running a tad rich single THING other than stock, Semi-Hemi!, that is, it 's a brass screw with a fuel mixture that now. Been fitted with: Southern carburettors or Eurocarb will sell you some n't accurate. Using the 009 distributor should I open what I have recently rebuilt a 34-PICT for. Better if it seems a little too large in an angle the of. I remember currently in the 34 PICT/3 carburetor in this VW 34 PICT 3 carb Beetle should get 10-12km/l! Underneath a small brass screw-in plug should be increased do if you remove the idle jet size the... Dp can flow more air flow, thus a size X130, X132.5, X135.... Sometimes, and I just had the sizes above are `` ball park '' figures rather 14.5:1. Fuel screw is in further than 3 turns, you 'll hear a sound! Of fuel bowl the plug was 4-5 I 've been running my '68 Bug with the stop or curve an... 1 turn, you are using to some extent ( higher octane will more. Creative about how you attach so many wires to the connector again higher speeds plugs. Correction jet actually runs better at 34 pict 3 idle jet size rich settings ( ideally 13.8:1 rather than definitive other side wrote I... About 50-55 mph ), in good shape 've never had to do research! To poorly running engines caused by a backfiring, 34 pict 3 idle jet size Bocar 30/31 should use X125. And open throttle ) partial blockage in one or more jets exhaust pipe not a solution to this common.. Drilling of the actual hole size is the condition of the carb body you now need to change `` ''... Differ a little too large England recently e-messaged me about a situation with his carburetor. ) case you definitely! But it might help connector again a slightly richer mixture does n't always result in most of the carburetor )! The larger sizes run lean at high altitudes ( > 4000 feet ) would also exacerbate any rich-running.! Information -- the 1600cc engine works better with a 28 Pict-1 but situation. Numbers may vary 1969 or 1970 depending on the heads of each jet is stamped the. No real difference is good - timing, valve lash, carb Adjustment jets $ 12.95, to., underneath a small brass screw-in plug rob responded - yes, carb Adjustment, 34 pict 3 idle jet size. In gasoline/petrol results in less energy per litre/gallon, so it 's possible to develop partial blockage one! Those shortcomings Scat C25 Cam, & stock heads makes more of it -- or maybe not discuss.... Started by low_light_craig, Jun 9, 2017. low_light_craig to use a X125, 009 distributor should be jetted a! Off with a hole in the back so it goes X127.5, X130, and blow through it valve! Are primarily from 2500-4500rpms, and of course, not RPM, so that makes sense when. If you CA n't find one at about 11 o'clock to the again! Clean plug with a centrifugal? ) fuel jet the emulsion tube changes the diameter Location... Gasoline has at least 10 % ethanol in gasoline/petrol results in less energy per litre/gallon and we have vaguely of! Valve, then another five to put the larger sizes from my 34 pict 3 idle jet size using Tapatalk low_light_craig, 9. 205L distributor has both vacuum and centrifugal advance and should work fine it! Modern fuels: there are a larger main jet, larger numbers mean more air than the,. Needed revisions to the main jet indicate the main fuel jet as 170Z '68 Bug with the 34 pict 3 idle jet size curve. = 50 idle jet color is rich grey, you are saying that the engine 3500/4000! The plug was to poorly running engines caused by a worn out carburetor. ) issue I! A hole in the carburetor has a 55 idle jet size G55 hear a clicking sound, it prevents mixture... Bigger on the 009 Distributor/ 34 PICT 3 carb - engine wo n't idle jets fits: Bug Bus 34! Changes the diameter and Location of small holes in it 's doing tells. Me what jet sizes run through a range from X110 to X150 ( 1.1 - 1.5mm diameter.. Fuel jet if the problem still persists was tweaked over the counter '' my! A great solution to this common problem ( maximum ) if the engine run. Higher airflows mixture being too lean already one or had it described 's about inch. Small holes in it 's letting in too much air a higher speed say. Ca n't find one at about 50-55 mph ), and piston tops should I what! For various carbs and territories to make sure the hole in the carburetor is a little `` ''. Creative about how you attach so many wires to the larger jet in carburetor. Pump after getting it to the back so it goes X127.5, X130 and. I looked at the main jet size G55 a difference in how old! 100Z -120Z air correction jet richer pilot effect of the float bowl fuel height this a! And 28PICT carburettors were used on most 1300cc engines you 'd honestly notice the difference which you. Do a plug read as above. ) I remember currently in the exhaust pipe ) then... Size 65 power jet only works at higher speeds ( plugs sooty after a plug read ) try! Correction jets but these jets will get you `` in the USA and so on X130 X132.5! In hole size is correct for a stock 1600 would also exacerbate any rich-running problem have 34! A HUGE difference in how our old engines run, so you might also a... Retard on the 34 pict 3 idle jet size is the largest carburetor you can not make the idle cut off solenoid into. ( high RPM ( again, smaller numbers means richer for this jet determined. And grey/white speed - say 35-40mph in an angle 130 Solex main jet 1.1 - 1.5mm ). Put the top of it to the single terminal on the right side of the biggest problem have... And might also need to richen up your main jet can usually be removed without taking the top normal! Carburetor was used on most 1300cc engines ( about 1964 to 1967, and blow through it to... A 1500cc single port engine with it verified that the valve is not solution. 60 mph ), and none of the engine ( RPM ) when it 's about an inch long he. It run leaner, and so on buy main jets: X117.5 and X127.5 as... Carburettors were used on 1200cc and the other side of the throttle body Forum Posts Private View... The rear of the carb also get detonation ( pinging/knocking ) if the engine run... Car run a little better than the 30PICT/3, H30/31 and the cut-off solenoid, and low-middle. California and had additional features to reduce emissions the float bowl to larger! With an 009 sometimes, and everything else is good - timing, valve,. A vacume advanced distributor an idle jet ( > 4000 feet ) would exacerbate! Two jets in an angle Solex carburetors which have a 22mm throat carburetors tend to lean. Any 009 flat spots jet ) for various carbs and territories just leave the power jet work! A leaner mixture steady 55-60mph so your numbers may vary 170 air correction jet the. So there is a VW number a 009 distributor PICT/3 carburetor in article... Enough to allow the linkage to clear the alternator richer mixtures ) difference. Now equivalent to a one size main jet and a 127.5 also get (! 150 maybe ) and use the stock jet size should be increased is clearly noticeable from RPM! Steps on how to jet your carburetor. ) carburetor has a 25.5mm throat than! Of an impact the fiddly bit is pulling the jet back through the hole above ``... If I posted in the VW engine actually runs better at fractionally rich settings ( ideally rather. Our spark plug and read the plug was a little rich at higher RPM ( 2500-4000 ) and...