Su carb needle removal. Aluminum jaws would also work.

Su carb needle removal. I have the kit labeled "B" - it includes everything you need for the H4 carbs in an MGA. The ZS carbs have a fairly limited set of needles. Lift off the piston spring. Unscrew the suction chamber retaining screws (3) and remove the identity tag. In part 2 the clean Comprehensive reassembly guide for HD carburetters, including throttle spindle bushing, float chamber, piston assembly, jet bearing, and centralization for optimal performance. (c) Remove the needle locking screw SU Carburettor - Needle and Seat Fitting SU carburettors are simple and very reliable in service but they can suffer from a few basic drawbacks. This page should help a bit. 400-grit works well. This will allow you to remove the spring, piston and jet needle assembly (Photo 4). A fi xed needle is rigidly locked into the piston which travels up and down in the suction dome (Figure 1). Jun 16, 2023 · There's also fuel leaking out of the bottom of the first carb. I would like to try some different needles in my carbs. Actually, there are some errors in the chart, as some of the needles are for ZS carbs. needles are shaped with such a profile as will achieve the precise fuel/air mixture requirement for any engine load/throttle condition. Used in cars all the way up until 1993, these Aug 24, 2025 · Every part of the carb is treated like it is the most important part. Since there is already a very good source of starting points/applications for fixed needle carbs, this is for those floundering about in the wilderness that is the biased (swinging) needle example of the breed. The book of needle sizes gives a list of diameters for each needle starting with the diameter immedi ately under the. But the new needles are different and without collar and spring. Remove the vacuum chamber from the carb body itself. If your SU carb is overflowing chances are that your old needle and seat are bad and need to be changed. I studied the needle charts and found the standard needle for this carb to be FX. With this guide, we The SU carb is a semi-downdraft, variable venturi carburetor—semi-downdraft because the carb tilts toward the engine and variable venturi because the size of the venturi varies. In this video I take you through the SU workings, the adjustment area's and an Aug 26, 2022 · Sometimes things don't go as planned. The SU Carb Company Jet Needles Introduction to SU Carburetters H Type Carburetters HD Type Carburetters HS Type Carburetters HIF Type Carburetters Thermo Carburetters AED Electric Fuel Pumps Mechanical Fuel Pumps Choke Units and Thermos Fuel Pumps Carburetter Maintenance and Settings SU Needle Comparison Chart 75 Articles New 289 gauze intake When your SU carburetors piss on the floor bugeyeguydotcom 6. WinSU will help find the correct SU carb needle for the following cars Austin Rover : Mini, Metro, Minor, Healey, Princess, Marina, Maxi, Allegro, Maestro, Montego, 200, Range Rover, SD1 Mar 20, 2012 · Dis-assembly Remove the carbs from the car. Hold the Dec 1, 2012 · Remove the two screws that hold the suction chamber in place. Jul 27, 2016 · The "369" needle is from Beck Arnely and is the same as the SM SU needle. Reading my handy-dandy old school shop manual, it mentions that this could be the result of debris getting into the needle and seat. Showing how to replace the needle and seat on an SU HS4 carburettor, however the procedure is very similar across the model range. Remove the piston damper (1) and its washer (2), if fitted. 90” fixed through to . (d) Lift the chamber assembly vertically from the body without tilting it (4). You may need to do this every couple of years or so, as modern To remove the needle in either case slacken the small grub screw in the side of the piston and slide out the needle. Learn how to tune HIF Type carburetters with precision. Jun 8, 2019 · The needle on the right is badly worn; that means the jet wasn't centered properly, and the other looks scored--replace (obviously). This video is a follow on of the previous video where we captured the carb performance during a test ride. This car sat for better than 20 years and I'm working to get it running again. Is there a good method to search the needle data base? I would like to get something richer in the 3 to 4K engine speed. SU needles come in two basic fl avors; Fixed and Biased. 2 (a) Lift off the piston spring. Jun 5, 2018 · Burlen fuels sell complete rebuild kits for your carbs including new bushes if required. NOTE: Prior to working on any carburetor, it must be completly removed from the bike, drained of all gas and dry. Learn routine servicing for H Type carburetters, including jet centering, cleaning techniques, float chamber fuel level checks, and needle size adjustments. SU HS Carburetor Needle Searchable Selection Chart Finding SU (Skinner Union) needles to make your car run right under all throttle conditions is a trying experience at best. In this episode we work on a MG MGB GT to disassemble and rebuild a pair of SU HS4 carburetors. . Find the right needle profile for your engine build with this comprehensive comparison tool. To check the needle fitted, remove the pistonjsuction chamber unit. Jan 1, 2013 · In depth instructions on how to rebuild SU Carburetors or Carbs I have seen many videos on rebuilding these carburetors but have yet seen one on how to remove them. Photo 7. Way before we had the new breed of rubbish fuel with ethanol in it. The pointed end of the needle sticks into the jet. For example, when you suddenly open the throttle to accelerate, the depression created in the manifold causes the carburettor piston to rise, pulling the needle upwards with it through the jet orifice. SU Carbs Theory What happens inside? Setting-up Air Filters Pistons, Covers and Dampers Lifting pins Needles Jets Floats and Valves Butterflies and Spindles Throttle Pedal and Cable Return Springs and linkages Ports and Vent/Overflow Pipes Vacuum Port June 2017 Hoses July 2015 Flange Gaskets Heat Shield March 2018 Dates and Codes Choke Control Reconditioning Plug Colour V8 - which carb feeds Posted by Topic List Forum List Newer Older Start New Topic Su H carburetor needle removal #1 MIKE MESSINA Orlando, Florida, USA Sign in to contact Topic Creator (OP) Dec 13, 2015 11:23 AM Joined 11 years ago 12 Posts I am attempting to rebuild the carbs on a 51 TD I am having trouble removing the needle, i have removed the set screw and attempted to pull the needle out nothing. This is due the SU being analogue and the vast array of needle profiles available. I tried removing one of the needles and it broke off in the piston. Follow step-by-step guidelines for adjusting settings, ensuring emission compliance, and achieving optimal engine performance. Piston for free movement in the suction chamber 2. The centering tool in 'Kit B' temporarily replaces the needle to center the jet (with the fixing nut slightly loose press the piston down, tighten the jet fixing nut then remove the centering tool and reinsert the needle. I fit a new float, new gaskets, a new needle and bearing jet assembly. The SU carburettor is simple to strip. Since I want things to be as original as possible I decided to change the needles. John Twist demonstrates this critical step in the rebuild of an H type SU carb. I tried spraying it with wd40 and tapping the needle into the piston in hopes it would be free enough to fall out. Rebuilding a carburetor, let alone two of them, can be a daunting task because there are so many small parts involved and sometimes a carburetor can seem like an extremely complicated device. While putting in new jets, needles and seats, and a gasket set, I show how to set the float height, check jet bearing centering and Jan 27, 2015 · 1. HD Type Carburetter: Dismantling 1 (a) Thoroughly clean the outside of the carburetter. Being a plonker, I took the needles out before reading the instructions so I don't know which is the required sense. Thanks. Today I drove it 50 miles and this Choosing the right metering needle for your SU carby shouldn’t be like finding a needle in a haystack. Toggle navigation Information Carburetor Needle Chart Products 1-41 of 41 I clean up the SU HD-8 carbs on the '68 Austin Healey 3000. If you don't like Aug 27, 2012 · The rebuild kit you need for these SU HS6 carburetters is CRK 249. Link to rebuild kit: https://www. Chuck the needle up to allow high speed spinning and carefully remove 1-½ to 2 thousands of an inch diameter four eighths of an inch down, using very fine wet & dry sandpaper. Aluminum jaws would also work. Carefully remove the piston/needle. Towards the end of the 240Z production, and most of 260Z production, Datsun began to use the Hitachi HMB 46W ‘Flat Top’ carburetor. SU needles more much more varied. The needle moves in slightly against a spring, but won't come free. This kit doesn't come with the jet needles as they vary depending on the engine and carburetter number. I had the same happen after a previous period of several months without strating the engine. Slacken the needle damping screw, extract the needle, and check its identifying mark against the recommendation. The SU Carburettor is a beautifully simple and great way of getting fuel into an engine. Remove the air filters. Generally it's easiest to remove the filters first, then disconnect the choke linkage and separate the carbs at the throttle shaft connection (pick one of the four 1/4" nuts on the wavy linkages to loosen). In Part II will reassemble one of the carbs. May 3, 2020 · After soaking with penetrating oil, I put the needle in the vise using soft copper jaws with a vee filed in them, then turn and lift or pry on the piston. HTML and Perl have been used to develop this database driven charting and searching tool. Here is my go at replacing the float, needle and seat in my carbs, without removing carbs from the engine as there really is no need to. (c) Unscrew the suction chamber retaining screws (3) and remove the identity tag. SU Carb Service - Lite For those who wouldn’t know a constant velocity, variable Venturi, side-draft SU carb from an orgasmatron, the prospect of cleaning and performing a preventative maintenance, or even just touching them can be pretty intimidating…one wouldn’t want to break or mess up anythingall those complicated mechanical linkagesand add to that, the fact that there are two Step-by-step servicing guide for HD carburetters, including jet centering, suction chamber cleaning, float chamber fuel level checks, and correct needle size positioning. If your SU carb is overflowing chances are that your old needle and seat are bad and need to be changed. So- Is there any special trick or procedure I should know to remove the needles from the carburetor pistons? They are, for all intents, SU Carb History SU Books available Comparing Metering Needle Dimensions "Tuning" and "Synchronizing" SUs Tuning Tool Set Mixture adjustment Initial Mixture Setting After Jet replacement Damping of Dashpot Damping Oil The "5-7 Second Test" Damping Valve Function Thumbscrew of Dashpot Damping Valve keeps loosening Damping Valve Assembly SU Carb Applications Metering Needles Common SU problems Ever wonder where the dashpot oil disappears to on Zenith Stromberg Carburetters? Read this Zenith Stromberg Carburetor Repair Guide to solve the problem. The Float tab only sits on top of and applys pressure to the top of the needle to keep it in place. Lift the chamber assembly (4) vertically from the body without tilting it. They have few moving parts. SU Carburetors are very simple to work on and adjust. This guide is the last installment of our Datsun 240Z Carburetor Guide, so check that out if you ATTENTION! This needle reference was produced quite a number of years ago now. Jan 2, 2014 · To remove a stubborn metering needle, often the best approach is to first remove the set screw, then put a bit of PB Blaster in the hole, let it sit a while, then gently tap the needle on the end with a hammer, driving it in farther, after which it will usually come right out. These will be sent to Island Automation to be rebuilt co Feb 22, 2014 · I have a set of rebuilt H6 SU's that I would like to put on a stock 4A motor. If carb cleaner and silicone spray lube don’t fix it, we will! Exchange and same day service standard (customer pays shipping). Ref: AUD2179, AUC1336. Inside the body of the carburettor is a piston S. Take the front carb off first. Fit the correct needle and lock it in position so that the shoulder on the shank is flush with the piston base. Millions of SU carbs managed without needle roller bearings. Any help would be appreciated. has been a case of removing gum. (c) Unscrew the suction chamber retaining screws (3). I haven't seen much in the way of step by step instructions or video tutorials for rebuilding SU HIF 4 carburetors so I decided to make one. 49K subscribers Subscribe May 18, 2017 · This holds the carbs together as a pair and saves disturbing the spindle and its settings. (b) Standard suction chambers. It's time to rebuild the SU carbs of my 1975 Jaguar XJ6. HS4C and HS8 Carburetter: Dismantling 1 (a) Thoroughly clean the outside of the carburetter. The needle feels like it has a spring in base. Beck Arnely produced the needles supplied in their carb kits and had their own ID numbers. For that problem, replace the rubber grommets. Fixing DRIPPY SU H-Type CARBURETORS -- CB-106 At 07:10 PM 5/9/05 -0600, Earl Chilton wrote: "You mention that SU-H4 carbs with the side float will at times, have a minor leak. (b) Unscrew and remove the damper and washer. We will discuss the SU needles here. Carburetor TOOL KIT Instructions - CB-130 Above: Tools in package and spread out Below: Rods set up in the carburetors TUNING TOOL SET Instructions for checking and adjusting S. (c) Remove the suction chamber retaining screws and remove the chamber without tilting it. In this video I show you how to disassemble the carbs and inspect all the parts. Best viewed in Google Chrome or Mozilla Firefox (not supported in IE). Rebuild kit CRK 249 for SU HS6 carburetters Needle chart SU carburetters Volvo B14 B16 B18 B20 MG SU Carbs by model yearCarburettors Models by year Jun 11, 2019 · Right-hand rubber float chamber adapter for SU HS2 and HS4 carbs; used in twin-carb applications to set the carburetor floats at the proper angle. (d) Lift the chamber assembly (4) vertically from the body without tilting it 2 Ball bearing suction chambers (early type). How many SU “rebuilders” engrave serial numbers on the throttle shafts? Sep 15, 2025 · Tuning your Datsun 240Z’s SU Carburetors can be extremely tricky, but when armed with a proper understanding of their functionality, the right tools, and a little patience, you will be able to get them running smoothly and delivering the appropriate amount of power under all engine circumstances. MN shoulder should be flush with Dashpot bottom surface as shown here: The piston features the adjustment for the needle, this adjustment is done using a long allen key pushed sown the damper tube in the top of the piston. The carbs can be removed, worked on, and eventually refitted as a pair. SU carburettors can theoretically perform better than modern computer controlled fuel systems. Photo 6. (b) Carefully lift out the piston and needle assembly, and empty the damper oil from the piston rod. 5 days ago · Tuning your Datsun 240Z’s SU Carburetors can be extremely tricky, but when armed with a proper understanding of their functionality, the right tools, and a little patience, you will be able to get them running smoothly and delivering the appropriate amount of power under all engine circumstances. Is there a good "how-to" somewhere which lays out how to remove the carb, inspect the needle/seat, and reassemble? Try to get the tab pushing up approximately perpendicular to the valve needle, but don't go crazy trying to make it perfect. Jun 3, 2018 · It would be hard to duplicate such a thing on a multi-carb setup like these were originally, which is probably why you rarely see someone polish up their own SU needle, but on a single-carb application like this one, I imagine one could spin one down by hand that would work at least passably well, if the material removal could be controlled. No go. I removed the locking screw and expected it to just pull out. When adjusting the needle in the fully-assembled carb, be aware that the rubber diaphragm is the only thing resisting rotation of the piston. A hex bolt that passes through the carburetor body secures the float chamber. If you have one of those little SU toolkits in the blue plastic pouch, you can use the jet wrench as a float height gauge. Centering the jet 5. SU has been making carburetors (or "Carburetters" as they call them themselves) since 1904 and the number of different models runs in the hundreds. Carburetors 1. I thought I would check with the Jag wizards before getting too aggressive with it. Ensure that when Jun 10, 2023 · We show you how to rebuild and tune the popular SU carburetor for your British classic. It is very reliable, but it can become dirty and choked — and some parts wear out. Oct 31, 2019 · An overview of everything you need to know about the SU carb. Jan 12, 2017 · I loosened and removed the set screw from the side of the piston, but the needle did not slide out. Reassemble the pistonjsuction chamber unit. Carbs and parts are covered by a 3 year warranty. In order to find the correct part for your specific carburetor, it helps us if you have the so-called "tag number" at hand. May 6, 2017 · Saturday, 6 May 2017 SU Hif4 carburettor removal and carburettor strip There are a few signs that my carbs really need some attention: Firstly, and most obviously, the idle is really rough- its hesitant and lumpy and sounds like a car that's always running on the choke. " They could leak at the rubber grommets between the float chamber and the carb body (banjo bolt mounting). Berry Feb 11, 2021 · I'd first remove the Carb Domes, and inspect condition and position of Metering Needle to assure a starting point and to take note of any obvious differences. Apr 2, 2006 · Library Article: Cleaning up a ratty old pair of MGB HIF4 carbs to better than new condition. Comprehensive dismantling guide for HS2, HS4, and HS6 carburetters, covering suction chamber removal, jet assembly disassembly, float chamber access, and throttle spindle removal. Jun 12, 2017 · Hi Michael, I am not sure how much you know about SU carb tuning so i will start from the beginning basics. SU Midel has developed Haystack, a handy tool that can compare or match SU needles from 0. In the photo above you can see the slimmer profile of the AAA needle at the top against the standard needles fitted in the HIF carbs. Remove the suction chamber tops 3 small screws on each. Use our needle comparison chart to find the perfect needle profile for your carburetter. With the engine cold ( it is much nicer to work in a cool engine compartment) you will be making preliminary checks prior to any adjusting. I loosened the side screw but cańt get it to budge. Jul 9, 2015 · I need to change the needle on my AUD465 carb. If you'll pardon the iffy video quality and my Mar 13, 2019 · Being an oft-voiced question on the message board, I thought I'd share it with you. I had a set of new "RH" needles and no stock needles so I installed them in the carbs. I had a look on Ztheray's site, they use lots of exclamation marks whenever they mention "roller bearings" but I couldn't find where they state why they are needed ? They mention binding / air leaks / etc but simply getting them bushed or reaming and fitting an oversize throttle shaft should take care of these problems just as Nov 15, 2010 · Video disassembly of an SU HS2 carburetor, demonstrating damper, suction chamber, spring, air piston with tapered needle, body, choke, throttle disc (butterfly), float bowl (4 moving parts). It was the only suggestion I could find on web search. Synchronizing 3. I use blue threadlocker on the screws. Here we show you how to install a new needle & set and a new float. To remove an old needle that you may want to re-use: remove the jet locking screw and pull gently on the needle with your fingers. Once you loosen an adjusting nut and a securing nut, remove the whole jet assembly. ithdraw the needle. 2 Ball bearing suction chambers (early type). com/gbproducts/more 5 days ago · Datsun 240Z Carburetor Guide – A Complete Guide to 240Z SU Carburetors The Datsun 240Z’s SU Carburetors featured a simple design that delivered fantastic performance when operating well. Mike Nov 26, 2020 · How do I remove the needles? I removed the locking bolt already, but it would not come out. I don't want to damage anything by pulling too hard, and tips to get this out? I am attempting to rebuild the carbs on a 51 TD I am having trouble removing the needle, i have removed the set screw and attempted to pull the needle out nothing. 2 days ago · Hitachi produced two carburetors that were used on the 240Z and 260Z. The float (brass or plastic) can become punctured and when weighted down by the fuel Comprehensive reassembly guide for H Type carburetters, covering throttle spindle installation, jet centering, piston assembly, float chamber setup, and linkage reinstallation. Apr 16, 2021 · Greetings! Any secret to removing the needle from the piston without damage? I want to see which needles I have. Is there a trick I should know? This are SU HIF4 for my 1974 MGB. Also get two new brass set screws; if they don't secure the needles properly the needles can drop into the jet causing all kind of fun and consternation (running on 3 cylinders). It has only one jet (except in a few special types) and very few moving parts. ADJUSTMENTS (l) Needle-changing (for mixture ratio altera- tion) If the general mixture strength is suspect, or simply being checked over, first remove the suction chamber and piston unit, and, after slackening off the needle clamping screw, extract the needle and check its identifying marking against the manufacturer's recommendation. Mixture strength 4. In this video I remove the carburetor from the car and disassemble them for a rebuild. Work on only one carb at a time. To swap the needles, you will need to remove the dash pots and the will mean undoing the three screws holding the pots down to lift out the pistons. If it cann be removed easily, tap the needle inwards first and then pull outwards. Learn how to reassemble an HS carburetter correctly, including throttle disc positioning, needle guide alignment, and ball bearing suction chamber reinstallation. Step 2: Suction Chamber Removal (Ball Bearing Type Jan 3, 2020 · After not driving my TR4A for four months I found both the Viton-tip float valve needles on the SU HS6 carbs to be firmly stuck shut. Thanks in advance. The most common Hitachi SU carburetor seen on the 240Z is the HJC46W ‘Round Top’ carburetor. Jan 11, 2011 · Cleaning my 2 SU HS4 AUD 325 carbs I discovered that the needles were AAA with a collar and a spring. Skip (´68 2+2, with triple carb conversion) Remove the suction chamber retaining screws and remove the chamber without tilting it. Apr 30, 2007 · Modifying SU Carbs Racing Technology Nov 3, 2021 · S. Hold the piston firmly and pull SU Carburettors The SU carburettor is a relatively simple design but has proved to be very effective. Mar 7, 2013 · You can get a 'jet centering tool' for SU carbs. partsgeek. Work in a well ventilated area, away from any open flames or sparks. The often underrated SU offers good versatility and reliability. The labels on the carbs indicated AUD331, so according to a needle chart I needed spring-loaded needles with code AUD1538 KN. HIF Type Carburetter: Dismantling Step 1: Suction Chamber Removal (Standard) Thoroughly clean the outside of the carburetters. (017722 412500) If your car is fitted with the GB engine then the correct needle is FX –Standard No 6 Rich. Photo 8. This guide is the last installment of our Datsun 240Z Carburetor Guide, so check that out if you In this video I remove the SU HS2 carburetor from my 1098cc A series engine as it has been running very rich. HIF Type Carburetter: Dismantling 1 (a) Thoroughly clean the outside of the carburetters. Now 2020, and many a dynoed engine under the bridge, this fuel is causing a complete re-evaluation of what is a suitable needle for each engine build spec. If it doesn’t budge, resist the urge to grab the needle with a pair of pliers. If the needle sticks try tapping it gently inwards before again trying to pull it out. Carb Needles Carburetor needles for the classic Mini, Mini Cooper, and variants. SU carburetor tips for Triumph cars: read the comments on how to acquire optimal fuel efficiency and much more. Theory of operation: fuel mixture, venturi effect, pressure differential, throttle disc, air flow speed, variable choke, acceleration enrichment, cold starting jet. Fuel flow into the carburettor float chamber is controlled by a usually effective ball valve design, however over time this system can be a potential problem area. ) To remove the carbs I first compressed the clamps and then slipped them along the link hose before easing the hose off the carb cross connections. Check Feb 5, 2015 · My SU carb handbook says that when replacing the bias type needle in a HS4 carb, ensure the needle guide 'gives the needle bias in the required sense (either toward the throttle disc or toward the air cleaner)'. Sep 13, 2025 · If you’ve tried tuning your Datsun 240Z’s SU carburetors and just can’t seem to get them to function properly, you probably need to take them apart and give them a good rebuild. If you google "Beck Arnely needles", their is a cross reference chart to SU. Remove the float bowl lid, use towels to remove the gasoline and debris in the bottom, followed by compressed air. shank or head of the needle and working down the length in increments of one eighth of an inch. U. Cleaning the carbs, fuel pump, etc. Give them a call and they can advise on what is needed. Secrets of the SU Carburetter - Part 2 Compare SU carburettor needles for your Classic Mini with our interactive chart. You need to get a base line on where things are at. Fuel level General Instructions: The vacuum controlled piston in the suction chamber Jul 4, 2011 · For on-the-car maintenance of the carbs, follow the advice given above. Carefully lift out the piston and needle assembly, and empty the damper oil from the piston rod. 125”. However, until a well researched new set of needle options can be offered up, the below are This is a follow on video and addresses the baseline verification of the SU carburettor , specifications , jet adjustment, float adjustment and damper. In this video I will show you how to replace the needle and seat on an SU Carb. S. The needle measurements seem to wander all over the place on the needle tables. The don't fit. at The MG Experience If your SU carb is overflowing chances are that your old needle and seat are bad and need to be changed. Do not ben Dec 29, 2024 · I'm rebuilding a pair of SU HS6 carbs off a discarded TR4A. rffmpk valifcffa hxovqh fsb xfaqx bwepa xwfrqo qunvm vylpxv zqexp