Quadrajet idle mixture adjustment tool. Oct 3, 2013 · Setting Idle Mixture and Idle Speed on Carburetors with Idle Mixture Screws to Pass the Smog or Emissions Test with a Tachometer Mar 13, 2022 · I have a 318 LA with a Edelbrock 4bbl intake and Rochester quadrajet. 59. 7L-2. Float Height measuring tool. 5 at idle with the vacuum advance plugged. M4 x . com Jun 27, 2009 · 18123 posts · Joined 2002. Mine is stamped on the left side of the carb toward the back of the secondaries. Use in conjunction with part #2021B springs. Our Part #. May 1, 2008 · A scan tool may also be used to indicate metering rod solenoid dwell. 95. Start and warm the engine. 26" long. Repeat the process for the right side idle screw. Most of the basic electronic inputs are familiar to modern driveability technicians, so we’ll leave feedback carburetor technology at that. Dec 26, 2018 · The first thing to do is to locate the carburetor number. Discover the features and adjustments of the Quadrajet carburetor, a leading-edge fuel Sep 23, 2018 · It should not be removed as many enthusiasts do. 99. place punch between two location marks over idle mixture plug. $3533. PHOTO 3. The manual says to install the lean mixture gauging tool over the throttle side metering rod guide, so now is a good time to do that. $9. Adapters: Double “D” for GM, '79 and Newer; 4. $24. Also Known As: THX350, TH350, THX-350. GM Computerized Idle Speed Control Adjusting Tool. I experimented with adjusting it a little richer, but that did not improve vacuum, so I went back to 4 turns. 311" (#2010G) Idle Mixture Screws - (#2003A) Metric Hex Head Replacement Idle Mixture Screws (#2002) Idle Mixture Screws and Springs, # 17062905 (#2003) metric Idle Mixture Screws for Rochester & Carter (#2009C) Idle Mixture Screws, # 7048854, 7048858 (#2001) Idle Mixture Screws, 10-32 $4. Out, or counterclockwise richens the mixture. Pair of replacement Quadrajet screws, fits 1979 and later Quadrajets and Dualjets. www. Mar 17, 2024 · Some carburetors, such as the Quadrajet found in most GM vehicles, have a special screw and require a specific adjusting tool. Freeing up the APT to allow movement, allows you to raise or lower the down height of Nov 17, 2011 · Re: Rochester Quadrajet tuning You are more than likely referring to the idle mixture screws. Allow time for the engine to respond. I picked one up off the tool truck years ago, A quick search turned up this one; I picked up a kit for carbs at Auto Zone a few years back that comes with 5 different tips to adjust any carb that works great on Qjets. The same procedure should work on most QuadraJets no matter Fits brands including: Craftsman, Stihl, Poulan, Husqvarna, Weed eater, Echo, Toro, Ryobi, Homelite, and some brands that utilizes a splined adjustment screw. They can only flow as much fuel as Aug 9, 2021 · Mixture control solenoid fits 1981-90 GM Rochester Quadrajets and Dualjet carburetors. Then out until you get a smooth idle. Dec 14, 2020 · This can be caused by several things, but there is one item often missed by the rebuilder and that is the idle tube. 84. slots should not exrend beyond 1/8 inch past the marks. Manufactured by: Thexton Mfg Co. this tool is a must for rochester quadrajet carburetors if the mixture screws are the double d type or hex. Turn each mixture screw in (lean) slowly in 1/8th of a revolution increments until the engine speed starts to drop. Turn each screw out a bit for a start (maybe 1 turn). Unscrew the screws two and one half turns. Buick 1981- 1990Cadillac 1981-1982, 1986-1990Chrysler 1985-1987Chevrolet 1981-1990Chevy/GMC Truck 1981-1986Dodge 1985-1987Oldsmobile 1981-1990Plymouth 1985-1988Pontiac 1981-1990. To begin, make sure the carb is unplugged and the engine is off. Sep 29, 2004 · Product Description. Trying to drill or grind away the caps is nearly impossible as they are made from hardened steel. The Thexton tool used to be the most common double-d carburetor adjusting tool, but it looks like Lisle also has one now. 7 grams of air are required. Do this until you get the smoothest idle and the vacuum meter stays steady. So actually, you have two tools in one! Apr 30, 2019 · If your carburetor has a main jet adjustment screw at the base of the float bowl, turn the screw clockwise until you feel it just touch the seat inside the e Mar 29, 2016 · Next with the transmission in Park and a vacuum gauge hooked to read manifold vacuum, adjust the idle mixture screws in small increments until you can get the highest vacuum reading with the leanest idle screw setting. 2L EnginesTool is Zinc Plated to Resist RustNote: Be Sure Fluted End of Filter Matches WrenchFour Adapters Conveniently Store in the Comfortable HandleFor Adjusting Idle/Mixture Screws on GM Step 3. Idle Adjusting Screw Spring. Depending on the air bleed used, you either adjust the air bleed and not the idle mixture screws or you don't adjust the air bleed and adjust the idle mixture screws to achieve the correct dwell. It has three electric connections: electric choke, Throttle Position Sensor output and Mixture Control Dec 9, 2023 · Unlock peak engine performance with the Quadrajet idle mixture screw setting, a dynamic duo tuning technique. We like to work with adjustments that are about the width of the screwdriver slot. Applications: 2 mm double-D - VaraJet lean authority screw and idle air bleed; and DualJet and QuadraJet mixture control adjusting screw. Great for fine tuning your Quadrajets cruise Air/Fuel metering. late models-cut 2 parallel slots on either side of the location marks using a hacksaw. Bruce Quadrajet Idle Mixture Screws Idle Mixture Screw- 10-32 x 1. 3. 311" (#2010G) Idle Mixture Screws - (#2003A) Metric Hex Head Replacement Idle Mixture Screws (#2002) Idle Mixture Screws and Springs, # 17062905 (#2003) metric Idle Mixture Screws for Rochester & Carter (#2009C) Idle Mixture Screws, # 7048854, 7048858 (#2001) Idle Mixture Screws, 10-32 . Turn the mixture screws, alternating Quadrajet Idle Mixture Screws Idle Mixture Screw- 10-32 x 1. A whistle with air will indicate a clean passage. On average, basic adjustment tools start at around $10 to $20. Views: 2,888. 67 Apr 24, 2006 · 1. This information helps you figure out if the carburetor on your motor is the one it left the factory with. 311" Carburetor Idle Mixture Adjusting Tool Fuel Inlet 1"-20 Threaded Insert Coils- (5 pack) Jan 20, 2011 · Here's how to find and adjust the mixture screws on your carburetor. ( 10 ) Part Number: LIL-55250. When the mixture screws are all the way in they cut off the flow of gas, thus the mixture Plugged that one and now the engine holds 15" of steady vacuum. Carburetor Idle Mixture Tuning. Travis. 83. Step 3. The only way to adjust the idle speed is with the throttle adjustment screw. Aluminum adapter inlet fitting allows use of high performance racing fuel hoses and fittings. Apr 20, 2023 · The Rochester Quadrajet is a four-barrel carburetor that was first introduced in 1965 by the Rochester Products Division of General Motors. Model: 54354. the flexible shaft allows the tool to clear hoses and other items normally blocking the use of a tool on the car. Always make air fuel mixture screw adjustments with a warm engine and the engine running, so you can listen to how the adjustments affect the engine’s idle speed. Hook the vacuum meter to one of the vacuum ports on the intake, or the carburetor. The idea that there is some magic position for the idle mixture screws based on number of turns from seated is irrational--there are more than one thread pitch used for idle mixture screws over the years. They usually have a few tips for the common carb adjustment points. Past idle the primary metering circuit comes into play and then the mixture is controlled by the power piston spring, and the primary metering rods and jets. Set to the height for the float and measure. Quantity: 2 idle screws. 5mm Hex for '78 and '79 GM; 1/4 “ Hex for Pre-'78 GM; 3/32” Hex for '78 and Newer Chrysler, 1. 2222. • Weight: 3 oz. How to adjust idle mixture on Rochester Quadrajet? For Rochester Quadrajets pick up an idle mixture adjusting tool at most auto parts stores. invert throttle body. I'm In Photo 178 the solenoid adjusting spring (also referred to as the lean mixture adjustment spring) is being pointed out and next the solenoid is positioned over it. Adjust the idle speed to the manufacturer's specifications using the idle speed screw. 285" overall length. 4 245 ratings. Oct 17, 2021 · We show the process to adjust fast idle speed with choke active on the quadrajet and how to set curb idle speed when choke is fully open. Feb 20, 2023 · Adjusting a Rochester Quadrajet 4 barrel carburetor is a complex process, but can be done with a few basic tools. The mixture control solenoid dwell setting is measured on the green single terminal connector that's in the harness in front of the carb. Sep 26, 2014 · You'd be smart to get one of those carburetor adjustment tools at an auto parts store. I had a problem when I tried it. Replaces OEM part # 17062905. Sep 23, 2013 · How to Remove Hardened Idle Mixture Plugs in a Rochester Quadrajet or Dualjet without Destroying the Throttle Body, and, My "Special" Idle Mixture Screw "Adj Sep 3, 2013 · Once you get that, you need to adjust your idle mixture (meaning both screws in a balanced way) using a "Vacuum Guage". 2. Fits: 1979-80 C-4 carburetors. 180. Manufacturer: Lisle. Use in conjunction with part #2021 springs. If your engine has a big cam and must idle at a higher speed, that's OK. The tool bends which will make adjusting easier. if it won't idle, then put more initial timing in it or hook the vacuum advance to a full manifold source. 5 mm hex heads. this tool can be used while the carburetor is on the car unlike a straight tool. SR: With an E4ME, you set the idle mixture screws until you're in the center of the dwell gauge on a 6 cylinder readout. Oct 9, 2020 · Here is my suggested procedure for setting up idle mixtures on the Q-Jet: Once the screws have been set to an initial starting position (4 turns out on 4MV carbs and 6 turns out on M4M), start the engine and let it warm up. Turn each screw in 1/4 of a turn and wait for a second for the vacuum meter to catch up. These tools are designed to adjust settings on computer controlled Rochester, DualJet, QuadraJet, and VaraJet carburetors on carbureted GM engines. This allows for calibration in either direction. e. Too hard and you will damage the screw. The Quadrajet is considered a three-piece design: air horn, float bowl and throttle body. 55250 Carburetor Adjusting Tool; 55250 Carburetor Adjusting Tool . You do admit to neglecting it. Heavy-duty flexible shaft for easy access. Screw the left idle screw into the carburetor until the engine starts to run rough. Feb 1, 2019 · We Were Able to Work With the Enclosed Idle Mixture Screws, But Encountered a Cutting Problem While Trying to Install the Secondary Shaft Bushings. Jun 20, 2009 · Sat June 20, 2009. Screw the idle screw back into the carburetor one half that number of turns. It has an extremely rich, eye burning idle, with the idle mixture screws having absolutely no effect on vacuum readings or idle speed(but it does seem to idle smoother with them turned all the way in). Turning the idle mixture screws clockwise (in) leans the idle mixture. The mixture screws only contol the idle mixture. break out throttle body to provide access to the hardened steel plug, drive plug out. My carburetor has number 17080504 on it. Remove plug from air horn and adjust your part throttle mixture. Sep 26, 2020 · This tool works, but I found it a bit clumsy. G'day, This is the tool from Autozone. Idle Mixture Screws with Springs, New 10-32 x 1. 311" (#2010G) GM Computerized Idle Speed Control Adjusting Tool Pin Vise Apr 7, 2013 · C3 General - initial setting on quadrajet idle mixture screws? - my car is a 68BB, but this is a later model rebuilt rochestermy chiltons says turn them in all the way, and back out 3 turns. Then, in 1/16th increments, slowly turn the mixture screw out until the highest rpm is Mar 10, 2014 · Computer controlled Quadrajet adjustment. Jun 1, 2022 · Showing the re assembly of the internal parts, float height spec is around 6mm from toe of float to casting. 5mm hex - DualJet & QuadraJet TPS adjusting screw. Quadrajet Idle Speed Adjustment. 1. Four adapters conveniently store in the hollow handle. #3 · Jun 27, 2009. I have both variations and prefer the adjustable airbleed Jan 1, 2023 · Adjust the idle mixture by enlarging or decreasing the pickup tube orifice size. Other carburetors may have a 4 corner idle mix adjustment and will therefore have 4 idle mixture screws. This tool has been selected to fit over the APT (adjustable part throttle) screw in the Quadrajets with internal APT. At the back of each socket is a square base that fits up into a small rubber handle. Time To Shed Light On Those Idle Mixture Screws. Carburetor Idle Mixture Adjusting Tool. 50 pitch thread (Metric) 1. Adjusting the APT screw and lean and rich stop screws. if the idle screws have no effect, you need to start out by trying to get the throttle blades closed farther by backing off the idle speed screw. Dimensions: 809 x 1079. Turning them in, (clockwise), leans the mixture. Much easier to see and adjust. If it has a problem off idle, maybe it needs to be disassembled and cleaned and throw a kit in it. Note any change on the vacuum gauge and/or tach. Oct 26, 2016 · Without these, you'll never get it right. Slowly unscrew the screw and count the number of turns it takes to make the engine run rough again. Tool is 6" long, and measures in 64th of inch. Secondary air valve tension adjustment can be made on underside of the air horn with carburetor installed on engine, all access is on external area of carb. Applications: 2mm double-D - VaraJet lean authority screw and idle air bleed; and DualJet and QuadraJet mixture control adjusting screw. Number 6 AN male fitting is flared to accept standard #6 AN female hose fittings. 1980 and up GM computer command control (CCC) carburetors with ISC motor. Use thin wire to clean out the passages completely. Adapter fitting replaces OEM Inlet Fitting and screws into Rochester Quadrajet & 2G casting using the original style sealing gasket. 2G Tools; 2G Tubes & Vents Aug 1, 2001 · Now start the engine and set the idle speed to around 850 rpm with the idle-speed screw. kd 2776 carb tool. For vehicles equipped with a Quadrajet carburetor, the idle speed adjustment process may differ slightly. Applications: • 2mm double-D - VaraJet lean authority screw & idle air bleed; & DualJet & QuadraJet mixture control adjusting screw. Applications: 2mm double-D - VaraJet lean authority screw and idle air bleed; and Dual Jet and Quadra Jet mixture control adjusting screw. Nov 30, 2013 · With the engine off, gently seat both mixture screws and then turn each one out (rich) two revolutions. Use a regular dwellmeter set on the six cylinder scale. This is a very small change. Adjust the idle mixture screws to get about 30 deg dwell. It was designed to meet the requirements for better fuel economy, improved emissions, and increased power. Two tools in one. Nov 30, 2011 · Only adjust each one about 1/4 or 1/2 turn at a time until you achieve either high vacuum or highest idle and then reset idle screw to idle speed you want. 4911C. Uses a common 3/16" hex socket. Adjusting air valve tension looser will Product Description. 4. Quadrajet Idle Mixture Screws; Quadrajet Inlet Fittings; Quadrajet Jets, Rods & Hangers; Quadrajet Linkage In this video, I'll show you the right way to set the mixture screws and idle air bleed valve on your electronic Rochester Quadrajet or Dualjet carburetor. $14. Idle dwell times generally run best at 30°. 85. Yes, I should have adjusted the idle mixture screws before attempting to fine-tune the carburetor with the vacuum pressure gauge. Oct 27, 2023 · This tool has been selected to fit over the APT (adjustable part throttle) screw in the Quadrajets with internal APT. Ensure that the choke is functioning correctly and gradually Sep 11, 2023 · Begin the adjustment process by noting the idle vacuum level and engine idle speed. Then move the first idle mixture screw in–clockwise–a very small amount. Your Price: $6. Thexton 350 GM carburetor adjusting tool is for the use on all 1979 and up GM carburetor. Thexton 350 GM Carburetor Adjusting Tool. And based on the dates and other data, mine is correct for my car and, most likely, the original one Jun 1, 2018 · The idle mixture screws require a special socket, and this Lisle 55250 carburetor tool will do well. Find a manifold vacuum port on the Quadrajet, such as the PCV port, and connect your vacuum gauge. These mixture screws were factory set. The idle mixture screws are secured with harden steel plugs. OEM quality idle mixture screws and springs for automotive and marine Rochester Quadrajet 4 barrel carburetors. Click here for the adjusting tools---- https://a Four removable bits are included to allow adjustment on various styles of Rochester idle mixture screws: Tool fits these Quadrajet Carburetor idle mixture screws: #2001 (Hex) #2002 (Hex) #2003 (GM double D style) #2003A (Hex) #2003B (Hex) #2003C (Hex) #2009C (Hex) Tool fits these 2G / Two Jet Carburetor idle mixture screws: #2006C (Hex) #2006D Mar 25, 2024 · Lisle Carburetor Adjusting Tools 55250. 410 inch "CE" code. The Quadrajet quickly became one of the most popular carburetors in the automotive industry, and Nov 5, 2019 · My original ‘75 Quadrajet did not have tamperproof screws, so the idle screws were completely in the open. 311" Overall length Thread size: 10-32 Qty: 1 Head Diameter: . Once those plugs are out of the way a special carburetor adjusting tool will be needed. Next, remove the choke housing and loosen the idle mixture screw located Jan 22, 2013 · These tools adjust various settings on Rochester QuadraJet, DualJet, & VaraJet carburetors on most GM vehicles having the 3C system. Dec 28, 2006 · Secondary Metering Rods. They usually have a springy extension on the end of a screwdriver handle. 50 Metric thread pitch. I Our Part #. One end fits "Double D" screws and the other fits 4. 182 Feb 28, 2010 · The OTC 7667 is designed to adjust settings on computer controlled Rochester, Dual Jet, Quadra Jet, and VaraJet carburetors on carbureted GM engines. for every one gram of fuel, 14. Very sturdy metal base, will last a very long time for Adjusting Tool; These tools are designed to adjust settings on computer controlled Rochester, DualJet, QuadraJet, and VaraJet carburetors on carbureted GM engines. Quadrajet Idle Mixture Screws Idle Mixture Screw- 10-32 x 1. Oct 2, 2008 · There are two variations of this adjustment depending on the air bleed used on the carb. 74" overall length. The cost of carburetor adjustment tools can vary depending on the brand, quality, and features. A slot bit, which fits the recessed Quadrajet idle mixture screws. $1. First run the screws in all the way until they seat, lightly. Note the reading on the vacuum Quadrajet Idle Mixture Screws Idle Mixture Screw- 10-32 x 1. Dec 3, 2021 · Product Description. 10-32 pitch thread 1. Adjust the mixture screws located on the front lower edge of the carburetor, into the carburetor until they lightly seat. Incorrect Idle Speed: An improperly set idle speed can cause the engine to idle too high or too low. Jun 20, 2022 · Fine-Tune the Idle Mixture: After adjusting the idle speed, you may also need to fine-tune the idle mixture screws on the carburetor to achieve the best idle quality and fuel-air mixture. › See more product details. 3630. These are the late type that were sealed in base plate. com. 7:1 i. 179. Product Description & Features: Heavy-duty flexible shaft for easy access; Four adapters conveniently store in the hollow handle; For adjusting idle / mixture screws on GM and Chrysler; Fit type: Universal; Brand: Lisle. For adjusting idle / mixture screws on GM and Chrysler. the other end is an open hex socket for the other type of mixture screw. Quadrajet Tools; Rebuild Services; Lean Mixture Adjustment screw for MCS. Mixture screws can be set 2 turns out each from Apr 23, 2018 · Too lean can cause an off idle flutter. Lean or fatten to get the highest vacuum reading over all (do NOT touch the idle speed screw to get higher Jul 25, 2022 · Step 2. [9] If you don't have the proper carb adjusting tool for your Ryobi, here is a simple hack to allow you to do it. . The flexible shaft tool makes reaching and adjusting idle mixture screws easy. Replaces Rochester OEM OEM MCS # 17067343, 17067344, 17077835, 17111102. Jul 7, 2004 · Works great for adjusting double-D Quadrajet mixture screws for ‘79-up carbs with capped mixture screws. 3/16" Hex Head. 6" Feb 27, 2021 · For gasoline fuel, the stoichiometric air–fuel mixture is about 14. Blow out with compressed air. Manufacturers Part #: 350. Then, remove the air cleaner assembly and loosen the four screws on the top of the carburetor. Here’s an example [9] These mixture screws were factory set. You hook that up to a vacuum port that has full vacuum to it. quadrajetpower. Very sturdy metal base, will last a very long time for you. Now back the screw out until the specified rpm is achieved. Adjustable Part Throttle (APT) screw allows adjustment of height of primary metering rods within the primary jets. Start the engine. 0. DON'Tdrill additional holes in the secondary main accelerator pickup tubes. Ergonomic designed handle provides comfort for easy and precise adjusts to the carburetor. Add to Cart. Aug 13, 2019 · Step 2 – Idle Air/Fuel Mixture. It is California first year computer controlled Quadrajet, originally installed on 305 engine. 03lbs. Photo 82 shows a close view of one in the throttle body. The thin tool is for adjusting the rich and lean mixture; below is the tool for removing the jets. If you are doing an initial setting after rebuilding, turn each screw out 2-1/2 turns fr Jan 2, 2012 · 1389 posts · Joined 2000. If you still have your old idle mixture screw, compare it to our new screws. Fits all Quadrajets with metric threads. Both computer controlled, and non computer carbs. Trying to adjust idle mixture on my 1980 Quadrajet after rebuild. Moving the screw down (clockwise) creates a leaner part throttle mixture. Pair of new idle mixture screws with new springs. is this a pretty good starting point for all the quadrajets? seems like it is running a bit rich, sometimes coughs a little 4902. With the engine up to operating temps, turn the screws in until the engine starts to stumble. The Quadrajet uses a Double "D" carburetor adjusting tool. In Part 2 of my series I show you how to properly tune your idle mixture circuit on your carburetor using nothing more than Two replacement Quadrajet idle mixture screws. The Quadrajet is a progressive four-barrel design with an air valve actuated secondary circuit. 1 day ago · One end fits "Double D" screws and the other fits 4. 5 mm hex - DualJet and QuadraJet TPS adjusting screw. 181. However, more advanced and feature-rich tools can cost between $30 and $100 or more. The idle mixture screws are located in the base plate for superior idle quality. Replaces Rochester OEM part # 7048854, 7048858 Quantity: 2 idle screws Idle scr Jun 24, 2014 · Originally Posted by rlsterling3. These are very small passages and get clogged easily with ethanol residue. There was some slag inside the socket that I had to drill out to get it to fit over the Quadrajet idle mixture adjusting screws. Navigate the intricacies of your engine’s idle fuel mixture and speed with precision – left for mixture, right for speed – all to achieve that elusive maximum vacuum reading. Or sometimes the metering rods can be stuck. • 2. After priming the carburetor for initial start up and setting the mixture screws approximately 2 1/2 turns out from fully seated, we were rewarded OEM quality idle mixture screws and springs for automotive and marine Rochester Quadrajet 4 barrel carburetors. Two replacement Quadrajet idle mixture screws. #2 · Jan 2, 2012. Assuming they were set properly was dumb. Slowly unscrew the screw and count the GM Computerized Idle Speed Control Adjusting ToolOur Part # 4911C. Quadrajet Carburetor Idle Mixture Adjusting Tool, 2G Toggle Navigation QuadrajetParts. Keep in mind: Turning the idle mixture screws IN will lean it out. 5mm hex - Dual Jet and Quadra Jet TPS adjusting screw Product Description. In this video I demonstrate how to adjust the fast idle on the choke of this Rochester QuadraJet. Correctly sized hex key is used to adjust the secondary air valve spring tension on the Rochester Quadrajet Carburetor. Clean the Oct 25, 2018 · - Mixture screws ended up about 4 turns out, and AFR was showing about 13. - During my first test drive the off-idle stumble was almost gone, but still noticeable. Measures the drop of the float tail from the center of the Quadrajet body. Take turns with each idle mixture screw. Feb 8, 2023 · C3 Tech/Performance - Quadrajet Carb adjustment tool - Double D screwdriver? - Does anyone have a good part number/ source for a Double D screwdriver that can adjust the Quadrajet carb fuel mixture screws? I have been searching for one, but for every It Works Great review, there are equal Didn't Work responses. Note reading, then start adjusting the Mixture screws. It is two bits in one. Choke Problems: A malfunctioning choke can affect idle quality, especially during cold starts. Set contains: 21 Teeth Spline, 7-Teeth Spline, Single D, Double D, Pac Man, and 4mm Hexagon. 255" Applications: Carter BBD carburetor Rochester 2G Carburetorssee more Lisle 55250 Carburetor Adjusting Tool . The choice of tool depends on your specific needs and the complexity of the adjustments you plan to make. Shipping Weight: 0. Remember, turning the idle mixtures screws in (clockwise) creates a smaller passage and a leaner idle mixture setting. Sliding handle fits securely in either end of tool. With the car running at operating temperature, use a screwdriver to adjust the idle mixture screws. Brand: Lisle. Estimated Price: $11. Turn the engine off. 5mm hex - DualJet and QuadraJet TPS Lisle 55250 Carburetor Adjusting Tool. The caps can be removed with a dremel tool, small chisel, small punch, and some patience. Start out with the mixture screws VERY SOFTLY seated, then open them 3 turns. Replacement Hex-Head metric idle mixture screws, easier to adjust idle mixture than original "Double-D" head. For use in Rochester Quadrajet models with APT located in the Throtle Body. Today drilled idle restrictor channel and idle tubes with a 5/64" drill but I think I went too far, the idle is now extremely rich, even with the mixture screws completely closed the engine still runs and puts out smoke on the exhaust. New Products; Auto Glass; Battery; For Adjusting Idle / Mixture Screws on GM and Chrysler. Float measurement tool, drop gauge. Unfortunately there is no data that can match the idle mixture screw to a specific carburetor number, so the idle screws are listed by size. Aug 14, 2013 · They turn out however much it takes to achieve highest idle vacuum, then back in about 1/8 or 1/4 turn, to lean-drop the idle just a bit. Turning the idle mixture screws counter clockwise (out) richens the mixture. Idle mixture screws on the Quadrajet must be adjusted equally to have a balanced air/fuel mixture. Fine tuning the air / fuel mixture screws. 4MX. Using a vacuum gauge, adjust the idle air/fuel mixture screws on each side until the maximum vacuum is reached. nb nq jr sj vw kw cv yu pf cz
July 31, 2018