Su carb fuel starvation Large vacuum leak. 11489 Washer (Fibre) on Banjo Bolt (AUC. For SU fuel pump service in the US, contact one of the following people: SY Series I and II 1965-1980. Before adjusting the carburetors, verify that the following items have been checked for proper operation. This image was published 1908 and 1909 A pair of SU carburettors from an MGB. Jump to Latest Two sources of info on the carbs, the ROM (official Jaguar workshop manual) but make sure you are on the HIF carb page as it also contains info for HS8s and Strombergs. Kwas 2004-2024, revisions On-Going. My average fuel consumption then dropped from 45mpg to a regular 60mpg. Removing it is a simple test. Is the adsorption canister configured such that the vacuum In addition to building the well known and much loved SU carburetors, they also went into the fuel pump business. Posted by Orange-77 . Insulating SU carb float bowls? #1. Moderators: notoptoy, S Allen, Solex68. It depends on how you look at it. Andydb; Aug 29, 2022; Norton Commando Forum; 2 3. This is basicly the same type of mechanism as "single point fuel injection" (throttle body ingection in GM terminology) which uses a pressure pump to inject fuel through a spray nozzel into the intake manifold or throttle body. 101-inch orifice for carburetors paired with fuel pumps and a slightly bigger 0. My understanding of what a float does is to control the amount of fuel available (basically make sure it has a constant supply) to the "jets" at any given time and to make sure the carb doesn't have too high a level so it ends up "spilling" out of the carb bowl. damper oil in SU and Zed-S carbs ( :wink: ), additive to crankcase for upper cylinder bits, tooth brushing oh, on second thought mebbe This is an update! I have got parts to rebuild the carb, I cleaned the carb, put a new mixture screw in and reassembled the carb. Needle info on a SU H6 Carb. 240" , below the top edge of the float bowl. depression then acts on the. T. There are fuel filters ‘socks’ over the tanks pick-up pipes and the big one by the engine. A temporary fix would be to fit an inline filter but a clean tank is the only real solution. Unfortunately, and more often than just occasionally, almost every owner has An excellent reference on most all SU carbs, covering the theory, rebuild and tuning instructions is the "SU Carb Tuning Tips and Techniques" by G R Wade, Brooklands Books (Moss sells it I think). So if fuel starvation becomes a problem with your carburetors, there is a tendency to question the condition of the needle and seat valve inside the Just in the process of fitting an electric fuel pump to my 109. Any leak in between the pump and carb should result in a smell of gas plus gas running out. 31 (Linux) MG MGB Technical Fuel starvation up hills BBS discussion. The Guzzi carbs will give the problem you are having at low RPM, I had it when on the Prescott hill on the sharp hilly corner, low speed, low RPM and a rapidly opening throttle will give the Diagnosing a fuel starvation issue which ultimately found the new synthetic floats from XKs to float higher than their old brass equivalents, to the point where the float level could not be set to allow enough fuel into the float TenTenths Motorsport Forum > Racing Talk > Racing Technology: Fuel starvation gerrards mallory park in mini turbo SU Carb My 3. 170" and 0. My 1972 Comando 750 used to have an SU. [Comments added !] The information presented is from my experience, it is not intended to take the place of an SU manual, or even just the Carburetter (British spelling), section of the shop manuals out there, but should be used in conjunction with their content. SU carbs were designed to overcome the type of problem you are having, as they will not allow the carb to fully open when you open the throttle fully. Seattle, WA, USA . Re: SU carb, performance tuning expert needed! Lean AFR's at hig 12. Look for a starvation related problem like rust in the Any thoughts on the following issue would be most appreciated. If the engine idles poorly, a vacuum leak is more possible. The old Facett pump was obviously over pressurising the carbs but never caused starvation. We do, however, prefer to supply the Weber 500 Kit with over ย£200. for the metrically challenged) compared to stock Amals or a Mikuni. I've: 1) replaced a suspected gummed-up steel tank with an aluminum one, 2) installed a double ended SU pump wired as two separate pumps, checked the carbs and pulled out most of my hair. 1 2 of 8 Go to page. If no fuel, check the system leading to the AED. dominicbeesley Well-Known Member. Fuel pressure is almost non-existent at all rpms - the needle of the gauge (which is a cheapie 0-7 bar previously used last week to check a 1980's EFi) just pulses fractionally up-and-down on the zero-stop. Adjusting the Carter BB-1 carburetor's high speed is a key step in ensuring optimal engine performance and fuel efficiency. The fuel line is 3/8 from the pump to the regulator, pump is mounted below the tank, reg is a holley dead head, tank is a standard FC holden tank, out of the reg i have 5/16 hose to the carb, the pump is a mallory comp 140 billet pump wich is way overkill for a SU, the reg is holding down to between 3. I managed to fix it. Top it up, and away it goes fine again. I encountered this problem years ago, when the SU pump quit and I dug a Facet pump out of my box-o-bits and installed it as a temporary replacement. No bubbles, all was fine there. Fuel starvation on RH corners, 28/36 DCD Weber. It has a mid 70’s 350 with a mild cam (very mild I put that in this winter) , Edelbrock EPS intake manifold and a 1406 carb. The question is, what would be the symptoms of the gas being too hot in that first carb, or is that even a possibility. Please assist. 1 of 3 Go to page. richness of air-fuel mixture. 37 mins. – scott64FHC danville, United States –Posted using Jag-lovers JagFORUM Re: Fuel starvation issue - 68 1600 SU Carb Setup Post by DivinDave » Fri May 29, 2015 2:33 am I cleaned out the fuel lines by first spraying some carb or parts cleaner in at the engine end, let it sit awhile and blow out with compressed air. Web if the steam valve is bad on the header tank you can get system depressurization, usually after turning the car off, and if the car is. The Shop Parts page for the SU Carburetters website. I gather its just a bit of a lottery- some cars seem to run absolutely fine with this set up An SU carburetor does not depend on fuel pressure, only on fuel flow. With the carb removed and float chamber filled, petrol issues freely it could cause fuel starvation if stuck open but it's default postion is closed (by spring But I guess when I get the SU it will be impossible to bend the intake pipe around to So I've followed the forum and fitted HUCO FUEL PUMP ELECTRIC SUCTION HUCO 133010 ENGINE BAY FITMENT. Re: Help! ZXi 1100 fuel problems!! Easiest thing is to find a set of CDKII carbs from a 96-97 1100 and put on it. Phoenix SU carb conversion. RPI say I need a Facet Red Top pump. Don't forget there's a fine mesh filter in the carb at the main fuel connection. Modified on: Fri, 13 Jan, 2023 at 10:44 AM. Re: Fuel starvation issue - 68 1600 SU Carb Setup Post by DivinDave » Fri May 29, 2015 2:33 am I cleaned out the fuel lines by first spraying some carb or parts cleaner in at the engine end, let it sit awhile and blow out with compressed air. ----- Yes it might do that. 14 sq inches of bore area. So all I really see it as is a glorified I also have a mate who had a fancy 3. (AUC2107) SU Carburettor Banjo Double Fuel Inlet 1/4" BSP suits 5/16" Pipe twin carbs (AUC1832) SU Carburettor Banjo Double Fuel Inlet 1/4" DCOE carbs should be mounted sideways to the direction of travel so that side-to-side accelerations do not cause the float to rise or fall (as the fuel sloshes). it helps to have a fuel filter fitted above pump so that you don't get a mouthfull of fuel I thibk this was a "pressure carburetor" like those used by the V-1710. Next Last. Yesterday started first time after being garaged for 4 months. txt) or read online for free. is that the jet is centred on the neutral point of the fuel level in the float chamber meaning that it in practise it doesn't matter which angle, (within reason) the carb is at, the jet sees the same fuel level. hi all, recently been having fuel problems with my v8 once i get a few miles from home decides to stall and refuses to start for about 10 mins in the most inconvenient places. I have now fitted the 4. Explore the evolution of SU fuel pumps from 1929 to modern electronic versions. 5psi? Carbs just had a standard rebuild. Re: Fuel Starvation by Granty » Sun Aug 30, 2015 6:46 pm Rich -- I should employ you as my personal google person -- I checked my fuel tap this morning on this problem carb & you'd be lucky if 100mm came out of it in 60 secs, and that was with the fuel cap off -- absolutely pathetic -- I then realised that the bike got "stutter" on the same part of the road on my plug Intermittent Fuel Starving Issue. Maybe just buy a manifold and run one of your knackered carbs It's much easier to get a worn carb working well on single carb setup I did this 45years ago with a Norton atlas manifold with a cut and re angled inlet And one of the worn MK1 s on my 850 I fitted it with a pancake air filter that I indented to clear the frame gusset It required the fuel tank removing and cleaning out with a descaler as was full of white powdery mess / blocked fuel lines/ fuel pump diaphragm perished and the carbs ( HIF) fully overhauled complete with new needles and jets due to the corrosion. Another cause of flooding, often mistaken for an over high fuel pump pressure, is caused by air trapped in the float chamber. . The angle is causing the fuel to run to one side of the fuel bowl causing it to have a high enough level to burn the fuel out of the carb enough to get the main jet out of the fuel in the carb. Carbs: Tried leaned, tried over en-richened, choked at 3500rpm, synched at 1500rpm, synched at idle, checked float levels, screens spotless. Home : Site Partners: SpotterGuides: Veloce Books : Related Sites: Your Link Here : TenTenths Motorsport Forum > Racing Talk TenTenths Motorsport Forum > Racing Talk > Racing Technology: Fuel starvation gerrards mallory park in mini turbo SU Carb The following warnings occurred: Warning [2] Undefined variable $search_thread - Line: 60 - File: showthread. 125" and 0. If the float level is too low the engime will starve for fuel especially in hi-demand situatioins like WFO, but it could also show up as light throttle surge. The other carbs seem to respond and are adjustable, but it’s hard to be sure as the stability of the system is delicate. After a while it will start and go for a bit. Hello, I need set of SU Carbs to possibly convert my 85 XJ6 fuel injectors to carb Where can I buy these set of SU Carbs either used or brand new. I ordered float valves from Burlen on 11/22, should arrive any day. Full Member; Posts: 199 Repeat with the rear carb. Excellent before and after sale service, many hard to find parts exclusively available in our online catalog. The bridge is the rectangular surface where the jet can be seen in the carb body. One or two 1¼" SU Re: Fuel starvation issue - 68 1600 SU Carb Setup Post by DivinDave » Fri May 29, 2015 2:33 am I cleaned out the fuel lines by first spraying some carb or parts cleaner in at the engine end, let it sit awhile and blow out with compressed air. fuel starvation #1. All ign components are new. The system does wear out and it Land Rover V8 SU carb 3. Here's what I've done so far: Distributor just rebuilt by Jeff, back to I disconnected the fuel line at the front carb and ran the fuel pump for one minute. If you can get the float level just right then the car will generally run way better and start much easier as the carbs will be working as designed. Red midget Robert G. Skinner took out a patent for a carburetter in which both the air and fuel passages varied in accordance with the requirements of the, engine. willie3051 William Leong. Ill be driving fine and suddenly she just dies on me, a bit like fuel starvation, once shes dies i pull the choke out and turn the key and after a few minutes of spultering she's up and running again however this wont last long and ill get the same scenario happen again down the road. You The carbs are kind of hard to tune at idle, and seem to adjust on the rich side (about 3 1/2 turns). 5oz. Basic Knowledge Even though the SU carburetor (carb) is a very basic yet precise instrument, some fundamental understanding on just how it works is needed to be able to deal with common problems and tuning. If I keep it matted, it will do the funky misfiring like your getting dribbles of gas into the carb. The inner walls of the fuel line where the filter goes were degraded and creating a barrier inside preventing the right flow of fuel. Lots of sediment in the bottom of the float bowl obstructing the jet feed. Offline. My official original 1960s Jaguar Spare Parts Catalogue identifies these washers as C. So - carb choke all fixed, carb reattached and pipes coupled up. The fuel sloshes to one side and the pickup tube sucks air, the effect though isn't felt for a while, as it takes time for that bubble to move through the fuel line to the carb bowl. Ok enough said. So far replaced tap, in line and fuel pipe. If the new pump is man enough where's my problem? SU Carb set up. The WO2 needle is closer to the factory "rich" RH needle. The only slight niggle is that when the fuel gets low, there's fuel starvation at the carb, resulting in uneven running. They may seem a bit long but they are very informative. Here's a step-by-step guide to help you with the high-speed adjustment: Safety First : Before starting any The HD Diaphragm Jet Type Carburetter and Auxiliary Enrichment Carburetter page for the SU Carburetters website. However, that consumes waay too much fuel. This topic is about my 1977 MG MGB. 25" H2 SU's would give 2. Thread starter TV8; Start date Jun 27, 2017; 1; 2; 3; Next. i dont know a thing abt these carbs and was wondering if anyone out there could HD8 SU Carb Fuel Starvation Hesitation Weakener Device. A standard MGA SU pump will not flow enough fuel for you. It certainly sounds like fuel starvation and I didn’t see you mention filters. I have many sets in stock (and many with linkage and manifolds) from Healey, to Jag, to MG Insulating SU carb float bowls? Posted by Red midget . I would expect the bowl to be somewhat full if I have a good fuel stream coming from the fuel line to the carb. Low pressure will cause fuel starvation during There is a fuel feed problem that can cause this symptom. Feels like fuel starvation, because if you ease off for a few seconds and press the pedal engine wanted to stall, indicating that that carb is too lean. B. Burlen Fuel Systems Ltd. 1938 and the HS carbs with the early nylon float and steel needle. The solution was to replace the carb fuel metering needles with a set that was richer at higher rpms. > SU Carburettors have become very expensive new if indeed you can stil get them, and used ones in good order are becoming almost mythical, Unrestricted return flow may, in extreme cases, cause carb fuel starvation at higher rpm, if Fuel flow looks fine - half a litre in twenty seconds or so, at fast idle (engine running on contents of the float chamber). You might also want to remove the fuel line at the pump outlet and the carb and blow some compressed air through it from the carb end to flush out any crud which may be in it. 187" with the float resting on the needle but not depressing it. 00 of this total kit price (and can be sold individually). I have a 5 gallon fuel tank, I use 1/2 fuel line, next the fuel filter, the fuel pump,1/2 insulated fuel line up the frame rail, to the fuel regulator,I run single fuel lines from the regulator, a gauge at the carb to the cowl outside,The fuel pressure is set at 71/2 PSI @ the front carb, I want to see where the preessure goes in the traps, two The SU carbs were used an many of the British cars. With the ignition switched off rotate the engine. I'm trying to rule out any kind of fuel blockage because this problem is permanent and always happens at the same point (whereas a fuel issue would surely be intermittent and cause problems across the whole range of running). 1 6 of 8 It is my understanding that the chamber should be dry and not have a puddle of fuel on both carbs. The Weber 500 Carb. Merlin SU Carburetors, at the bottom right is the updraft carburetor, which air is sucked into Essentially, we are able to use about 3 gallons of fuel if we're filled up. User actions. 5 Snatch engine problems. Intermittent Fuel Starving Issue #1. s. As does spraying around the manifolds, manifold gaskets or any carb. Go. 16 mins. Went out today for 25 minutes normal drive and it spluttered and died. This seems a bit overboard but that's what happens when you leave motors a long time without use. I am getting a problem which feels very much like fuel starvation with air getting into the system and then the car stops. 035. Crank the engine; fuel should leak from the plug. Fuel starvation at an angle isn't really an issue either. I had it up to 6 mm of the top yet the carbs will “self adjust” the oil level if too full. The midrange is very good, the high end a tiny bit weaker (or so they say). Had to charge up the battery but started up on first turn of the key, although was not running perfectly as had to do some tweaking due The fuel pump should have been running briefly to ensure that the chamber is full and the fuel level can then be seen in the jet hole. This was brilliant giving easy starting, loads of oomph and amazing fuel consumption figures Also used the earlier paper type air filter with the single carb front plate. New I can't get the idle down at all -- lowest idle I can get is about 1800RPM if I want to keep the carbs synced. Honesdale, PA, USA Fuel starvation is the opposite of vapor lock - its the percolation of fuel that results in flooding. Start the engine and ensure the fuel level remains within the correct parameters. Stay safe. Earlier example used a 'V' shaped What appears to be a faulty pump that is causing fuel starvation problems in the carburetors often turns out to be a leak in the fuel line at some point between the gas tank and the fuel pump. Copied from SU Carbs Page: Overflowing fuel bowls The fuel feed is a low pressure (2-3 PSI) system with a simple float and "needle valve" (See: Bowl-Valve) controlling the The Weber 500 Carb. 7-4. Genuine SU Carburettor Parts. Jump to Latest 21 - 40 of 148 Posts. The problem has always been air getting drawn in and I just fitted the electric pump to prove that it was fuel starvation that was causing the high revs problems. climbing a long steep hill in 3rd gear with foot to the boards. We have an SU Carb set up with a 1978 fuel tank, running the return system for the fuel to return to the tank. I changed it for a new fuel line and now its watching the sunset while purring like a kitten. Recently it's been displaying fuel starvation problems at higher RPMs. Zitch Jedi Hopeful. SU Carb Service possibly resulting in fuel starvation symptoms. The SU Carburettor is a beautifully simple and great way of getting fuel into an engine. 31 (Linux) I'd show photos but my old carb is at my parents house 200 miles away. If these is no fuel in Possible causes: Small filters at float bowl intake clogged. You should see fuel about 1/8″ or so below the top of the jet tube when looking at it with the parts removed. If the tank has rusted inside there'll be a brown sludge in the filter. Following is as basic a description of what's going on that I can manage! First you need to be comfortable with the main aim of any carb - to supply the SU, 1-barrel Carburetor Rebuild Kits and Parts. SU Carb Piston Spring BLUE/BLACK H8, HD8, HS8, Aston Martin Jaguar, Rover, light blue & black 4. If one carb requires many more flats than the other for smooth idle it is possible that the linkage is improperly adjusted and/or one or both carbs have a mechanical problem. I drilled a 1. You can reuse the stock SU fuel rail if you link all three carbs in a loop from the front outlet port to the first carb, the first carb to the second carb, the second carb to the thrid carb, and the trird carb to the rear outlet of the fuel rail. Go Down Pages 1 2. Now however, I am having an intermittent starvation issue whilst driving. If left alone for a bit it will start but wont pull away or SU single carb conversion - recommended. I thought Jim said that the pump should pump 16 oz (1 Pint) in a one minute period. George H. The other thought is the opposite of fuel starvation, and the slope is causing the fuel bowl vent to get flooded with fuel causing a rich run issue. 1937 was the year the ubiquitous H-type SU carb was born featuring a range of choke bore sizes from 1-1/8 inch to 2 inches in 1/8 inch increments; a carb to cover all applications and so successful was the design it stayed virtually unchanged right through to the end on the 1950s. Randall 56 TR3 TS13571L 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. If that helps, then the mixture is probably weak: make an adjustment or fit a slightly richer needle. Stalling at a stop is probably a misadjusted anti-stall dashpot. In 1905 Mr. Stalling while cruising sounds like fuel starvation. 9 built for his 101 which was initially run on SU's, it went well enough, but was still sore on fuel returning 11-12mpg. When this happens, the silence is deafening with the normal tic, tic, tic I disconnected the fuel line at the front carb and ran the fuel pump for one minute. 5″Hg, enough for 330 hp technically, and under boost, probably well over that. Topic List Forum List Newer Older Start New Topic. Problem: Sticky float jets (also called needle valves, ball and needle I will now do a few SU carb sets/month, but with my preference being to do specialty SU work. 0 PSI. Home : Site Partners: SpotterGuides: Veloce Books : Related Sites: Your Link Here : TenTenths Your Link Here : TenTenths Motorsport Forum > Racing Talk > Racing Technology: Fuel starvation gerrards mallory park in mini turbo SU Carb User Name: Fuel starvation gerrards mallory park in mini turbo SU Carb Racing Technology. US manufactured and ethanol ready. If you have dual SU fuel pumps it's possible that one of them isn't working and this might cause a power loss on acceleration. SU Carburetter Company By P. Symptoms: Fuel starvation and lack of power OR overflowing float and flooding/running rich. The fuel flow ensures that there is sufficient fuel present in the carburetor bowl, from which it is led into the carburetor (and then "sucked into" and vaporized in the air stream). Mechanical Fuel Pump: Fault Diagnosis. I went from the standard UM needles to UO needles which resulted in a 23% increase of richness at full rpm. Have been having fuel starvation problems on my 100 for about a year. 062" and 0. Knocked up a bracket to mount an SU ( puller type pump ) in the engine bay. Our expert team can advise on the best fuel pump solution for your specific model and usage requirements, whether it's for daily driving or weekend enjoyment. I have many sets in stock (and many with linkage and manifolds) from If no fuel is present this indicates a faulty AED. Can't see an exact answer to this in this thread as it talks about the pressure the fuel pump works at but I need to know the quantity of fuel required by the carbs that is required to be pumped. As you all know, SU stands for Skinners Union and was the well known and much loved SU carburetors, they also went into the fuel pump business. 8 FHC has a filter, facet pump, and regulator installed (in that order) in the wheel well. The location of the old fuel pump was right by the header, which cooked it (common problem), but the fuel lines are still close to the header, and the 7/8 carb is the first in line for the fuel feed. Gus Meyjes. When the choke is on and rpm = 3000 it enriches the fuel/air mixture (let's just say 10:1), but that the air 1936 and the company became SU Carburetors Limited. HD8 SU Carb Fuel Starvation Hesitation Weakener Device. Firstly, check the fuel filter. No fuel can be seen in filter. So it is very possible that you are starving. 6 RV8 into the MGB, which still has the standard SU fuel pump, electronic version. If I flutter the acceleartor linkage at higher R I'm having a similar problem. The SU H4 carburetors have the float chamber connected to the main body of the carburetor with a banjo bolt and two rubber grommets (you can wiggle the float chamber a little). The following warnings occurred: Warning [2] Undefined variable $search_thread - Line: 60 - File: showthread. Also the mixing is probably better in the single carb set-up. If the fuel bowls are able to pivot in a horizontal plane relative to the venturi, swing them further outward until they are in fore/aft alignment with Fuel Stavation? - posted in Problems, Questions and Technical: 1330 engine producing abiout 95 BHP with pair of HS4 SU Carbs, 286 cam When giving the car welly once it gets to about 5500rpm the car feels like its got fuel starvation ie it just stops accelerating and I have to back off Its running a SU pump mounted to the subframe So is this a likely cause and the same mileage that a new SU fuel pump will fail. pdf), Text File (. First, only after installing off-road needles and seats (part #1465) I got rid from fuel starvation and fuel flooding problems when off roading on steeper inclines. Started second kick and left on tick over for about 10 minutes. The carb body should not be tilted more than 5 degrees when installed so as to prevent fuel leaking into the throat. (The fuel input pressure to the carbs does not go to zero when the pump is shut off. 11/5/00 Hi Mad Ludwig (Ernie) & Knight Martorelli – Ernie & Mike, if you like, I can photocopy (and snail to you) pp/29-38 of the XK120, 140, 150, Mk 7, 8, 9 Owners Workshop Manual, Autobooks 702, by Kenneth Ball, “The Carburettors and the Fuel System” – these thoroughly cover rebuild, etc. now produces SU_Fuel_Pumps_101 - Free download as PDF File (. Tested fuel and air passages by squirting petrol through them - all clear. Going to remove the alloy fuel tank this HD8 SU Carb Fuel Starvation Hesitation Weakener Device Page 7 Rolls Su Carb Hesitation On Acceleration It has very few moving parts, usually only one fuel circuit, and far fewer springs,. Here's my question on carb mechanics - I'm thinking there is a difference between amount of fuel v. Roll Royce, Bentley, MG etc, They are very good reliable carbs. A secondary benefit with SU's is that for engines which require more air flow, the SU is limited to a two inch bore which gives around 3. Copied from SU Carbs Page: Overflowing fuel bowls The fuel feed is a low pressure (2-3 PSI) system with a simple float and "needle valve" (See: Bowl-Valve) controlling the flow into the fuel bowl. It has no ethanol content. But, after that, another problem New plugs, electronic ignition, coil, leads, fuel pump, in-line fuel filter, twin K&N air filters, carb floats and valves, carb shafts and butter-flys, carb gaskets and fuel pipes. Aside from the lean on top the SU's performed much better then the Linkarts. I now have the bike running and it seems to idle fine but when you try to throttle up quickly it acts like it is starving for fuel, what could be going on here and what should I adjust. BURLEN; SU; AMAL; ZENITH; AUSTIN PEDAL CARS; SKINNERS UNION CLOTHING; TEL +44 (0)1722 412 500 Our works restoration Despite running SU carbs for many years, I have been unable to solve my current problem. 0 psi, if i go any higher my float bowl The engine might be suffering with fuel starvation at hight revs. Used in Will this fuel pump (see link) work in my 1972 Rover P6 V8. TR4-Phil SU Carbs - HIF, a more finely honed instrument. Apparently the fuel being delivered is somewhat uncontaminated by the looks of what you cleaned out of the float bowls. Will not restart. HS2 Carb (13) hs2 (3) Fuel pressure gua We manufacture all SU, Amal and Zenith carburetters on site and while many are built to order we also build for stock too. pulling the choke seemed to fix it on the top end but makes it too rich on the bottom end. HS carbs with the later all nylon float and delrin type needle. Topic Creator (OP) If the fuel level is in the correct range, the fuel will rise in the tube to a point between 0. They started in the 1932/33 time with the L, low pressure pumps. TV8 0. I drilled the inlets a bit and raised the floats. The SU carburettor is a constant-depression carburettor that was made by a SU carburetors look and operate differently from the Holley and Rochester carburetors Americans are commonly familiar with and they sometimes are misunderstood and discarded as being unreliable or too difficult to keep in tune. Edited 1 time(s). Enrichment in the HIF is supplied by means of a separate fuel-path within the carb body between float chamber and constant depression area close to the jet hole. When I initially started it, it ran decently for about 5-7 minutes. Maybe bouncing as high as the first tick I believe I'm experiencing fuel starvation when I drive up the freeway. min. Almost seems like the needle sticks in the seat, restricting incoming fuel. DCOE carbs should be mounted sideways to the direction of travel so that side-to-side accelerations do not cause the float to rise or fall (as the fuel sloshes). Check the float level and make adjustments if necessary. BURLEN; SU; AMAL; ZENITH; AUSTIN PEDAL CARS; SKINNERS UNION CLOTHING; TEL +44 (0)1722 412 500 We are the worlds sole manufacturer of SU Carburettors, Re: Fuel starvation issue - 68 1600 SU Carb Setup Post by DivinDave » Fri May 29, 2015 2:33 am I cleaned out the fuel lines by first spraying some carb or parts cleaner in at the engine end, let it sit awhile and blow out with compressed air. G. Identify causes such as sticking pistons, low damper oil, or worn float valves and fix them. I’m wondering if I have fuel starvation on the rear carb - SU carb leaning out and the starving - posted in Engine: I have a 179 with a 3. Page 12 3. He said that he is willing to try adjust the jets and the float to fix the problem. The drawings, descriptions and photographs of both the HIF7 and the AED are actually quite useful: SU Carb, no power on acceleration. George, in spite of taking over his father’s business, Lilly & Skinner footwear distributors, had a better idea for a carburetor in the early automotive days. The original main fuel line to all three carbs on this particular car used Aluminium washers on each side of the Banjo bolts. Also how is the choke supposed ya it really seems like it just flat runs out of gas. If it is blocked that could be the problem. same type as fitted to the old morris minor discard the original petrol lift pump and pipe to the carb, blank off the hole but also retain a water trap in the same position. pump will sustain damage that is unseen, but it will cause rapid burning of the points in the pump. I have a single SU HIF6 on my 1972 Combat. rdb Rusty Browning. SU Carb tuning; SU Carb tuning. New rubber on all lines everywhere from tank to the SU carbs. If you have any spare Troubleshoot HD carburetter issues like erratic running, hesitation, and flooding. { CAUSE 1 } The carb is adjusted too weak { SOLUTION 1 } ADJUST THE CARB SY Series I and II 1965-1980. You said you changed the fuel filter in the glass bowl. Re: Fuel Starvation by Granty » Sun Aug 30, 2015 6:46 pm Rich -- I should employ you as my personal google person -- I checked my fuel tap this morning on this problem carb & you'd be lucky if 100mm came out of it in 60 secs, and that was with the fuel cap off -- absolutely pathetic -- I then realised that the bike got "stutter" on the same Original design incorporating a leather bellows which was replaced by a piston. Su carbs, What you should know before tuning. THE VAST MAJORITY of modern spark ignition internal combustion engines rely upon carburetters to provide them with the finely atomized fuel/air mixture which is necessary to enable them to perform satisfactorily. A little side note: that 0. There is a BSA service bulletin about this problem. I'm very satisfied with it and the gas mileage is very good (25 km/l, 65 m. There is definitely a process in checking the engine specs before working on carbs, usually check the tappet clearance, spark Re: Why dual carbs? I agree with Aerog & Nunyas; The main reason is the more even fuel distribution provided by multiple carbs. Pulled bowl off carb and hardly any gas was in the bowl. If the rubber grommets deteriorate they can leak fuel or possibly obstruct fuel flow through the banjo bolt. and Manifold account for just ย£650. Posted by Poundingsand . Many suspected carburetion issues are actually caused by faults within the ignition system, making this the first place to POSSIBLE CAUSE ; FUEL STARVATION. the bang,,bang ,,pop,,vrrroorm ,,pop,,bang . Spraying carb cleaner around the throttle shafts at idle has no effect. A single carb on a branch manifold is subject to twice as much vacuum as a carb in a dual system, so the main jet needs to be smaller than it is in twin carbs. Proceed as follows: Remove the float-chamber lid and check that the needle valve and float are free to move. If the new pump is man enough where's my problem? Gostaríamos de exibir a descriçãoaqui, mas o site que você está não nos permite. it still works out at 1/3 to half the cost of a new carb. its a great product. I can lower things a bit by backing out the idle screw on the front carb, but the screw on the back carb is already all the way out -- won't lower any more at all. of both the SU H6 (XK120, XK140, Mk VII, Mk VIIM) and the SU HD6 (XK150, Mk VIII, Mk The Rolls-Royce Merlin engine originally came with a direct carburettor, prone to cut-out due to fuel flooding in negative G. However an alternative which is suprisingly good is the Haynes manual on SU carbs. Posted by rdb . However, if I by pass the fuel separator and connect the fuel line straight from the fuel pump to the carb, then fuel starvation does not occur. Your carb works best with an average of 5. 1953 Austin-Healey 100. It'll tick over all day long, but balks at anything much over 2000RPM. A year ago I bought my brother-in-laws 62 impala SS. As you all know, SU stands for Skinners Union and was the brainchild of George and Carl Skinner. Peter SpqrEddie. the only way i can get the car to run is to dump some gas straight into the carbs. Allegedly rebuilt twin HS4 SU carbs on a 1147 Triumph Herald engine. 06 mins. Experimenting with lowering the float levels, I found that fuel surge and starvation during cornering became a problem if I deviated too far from the Fuel starvation issue - 68 1600 SU Carb Setup. Thread starter Zitch; Start date May 9, 2013; Share this page. Burlen Ltd are a leading online retailer of classic SU, Amal and Zenith carburetters, fuel pumps and components, based in Salisbury, UK. 3 crank, it has a eaton m90 blower running at 7psi, it has one 2" HS8 SU with the highest flowing grose jet needle & seat valve, it has a KX needle wich is about as rich as i can get, very thin and fragile, i have just fitted a brand new needle and main jet becuase the last one was slightly Fuel starvation issue - 68 1600 SU Carb Setup. High fuel consumption: Sticking piston: Dirty piston and suction chamber Jet out of centre Bent needle: Clean Re-centre Fit new: Hesitation at pick-up: Low damper oil level Incorrect oil grade (too thin) Top up Replace with correct grade: Float chamber flooding: Dirty or worn float-chamber needle valve (dirty fuel) Punctured float Incorrect I have replaced SU Carbs with Edelbrock Performer 500 cfm carburetor in my Range Rover Classic 1982 - then I could not even start the engine. In the mean time, I am going to pull the floats and adjust them a The Amal Concentric carburetors don't have enough fuel flow for an 850 even with twin carburetors, the fuel flow has to be feed up a bit to make it work with just one carburetor. The su carbs will work well even if a bit worn. G KNIGHT INTRODUCTION. Su carb tuning, part 1 - the basic. My point is that the SU fuel pump will last about as long as any other electric pump that is on the market for use on the MGs, possibly longer if it is an all electronic pump or one converted to solid state. Facebook X (Twitter) Reddit Pinterest Tumblr WhatsApp Email Share Link. A steady 70 mph gives 65mpg. Suspected Fuel Starvation. 2 Since engine vacuum is a function of the operating condition and air/fuel requirements of an engine, the SU carb is ideally suited to meeting the requirements of an engine by means of this direct feed-back loop, rather than Checked fuel line to ensure gravity flow wasn't hindered, steady flow all the way to carb. 118-inch one for gravity-fed fuel systems. In reply to # 302533 by GuntherR I race a Bugeye and in tight corners if the fuel level is below half-full I get a fuel starvation issue. Wont use carb cleaner on fuel lines again thanks for the advice. All of a sudden it started to splutter and died. Last edit at 2013-07-18 08 but perhaps it is more likely fuel starvation based on your analysis. 5mm (. SU HS2 carbs and fuel/ float level. I blew out alI the steel lines with shop air, both directions. The carb An overview of everything you need to know about the SU carb. Fuel filter full. Quick fix is to remove hose to carb and suck fuel thrugh pump - which will then pump fine. The Fault Diagnosis page for the SU Carburetters website. The car idles fine, upon take up of speed into 2, 3rd gear, I get a sputtering, starvation issue. L. New fuel filter. BentleyEight · Registered. Checked plug. They are telling me to find out the fuel pressure required for the car. Two 1. Fuel injection filters will trap particles as small as 10 microns but will clog up sooner if the fuel supply is delivering a lot of particles larger than 10 microns. My 3. Valves adjusted recently, 115lbs compression in all 4 cylinders. Fuel starvation gerrards mallory park in mini turbo SU Carb Racing Technology. Reply. the amount of fuel added to the air in an SU carburettor is determined by the shape of the needle, how far out of the jet the needle is and how high up the jet the fuel sits. BURLEN; SU; AMAL; ZENITH; AUSTIN PEDAL CARS; SKINNERS UNION CLOTHING; TEL +44 (0)1722 412 500; Carter had two standards: a 0. The Worlds Sole Manufacturer of Genuine SU Carburettors, Fuel Pumps and Spares. Sounds like fuel starvation,are you getting fuel,via the needle valve into the float chamber? Is the float level very low? Most SU carbs are designed to work with an over-supply of fuel to the The whole point of the HIF carb. This has been increasing gradually since about a week after I finished installing the dual HIF4 carbs, removed the ZS and the catalytic converter all Morris Minor SU Carb needle and seat kit with float lid seals. It's supposed to allow a slower decrease in revs and avoid stalling. It is the function of the carburetter to provide good atomization and the Re: Fuel starvation issue - 68 1600 SU Carb Setup Post by DivinDave » Fri May 29, 2015 2:33 am I cleaned out the fuel lines by first spraying some carb or parts cleaner in at the engine end, let it sit awhile and blow out with compressed air. Des Hope it’s helpful. What happens if the fuel level gets too low from adjusting the float height? Will it surge or hesitate at steedy mid-throttle? I may have moved mine a bit too much. However in twin carbs, you have better ram effect. The document provides an overview of SU fuel pumps, including: 1) A brief history of SU and the development of their various fuel pump models from the 1930s to 1960s. Posts 1,701 Location Hebden Bridge, West Yorkshire. Rimmer's don't know. Jump to Latest 101 - 120 of 148 Posts. At first it felt great but then I noticed that there is fuel starvation when cornering hard and a weird bog down in 1st gear in the middle of the RPM range. Posted by willie3051 . Wen cranking after a few weeks, the pump is pumping air - which it doesn't do very well -so takes a long time. SU Carb set up #1. 8. p. Requiring the choke to be constantly on is a classic symptom of fuel starvation . Does anyone have an opinion on this? MG MGB Technical Temporary Fuel Starvation Problem BBS discussion I have also added a small bullet type fuel filter within a inch or two of the fuel inlet to each carb fuel bowl. 38. If the pump chatters away before slowing and stopping and when turning the key to crank the engine restarts, or if there was no spurt of fuel, then the problem is fuel starvation, either because the pump is intermittently cutting out or dead, i just bought a '65 122s from a guy who rebuilt the stock su-hs6 carbs and he told me he hadnt adjusted them at all since rebuild. Float levels are correct. The SU and Zenith~Stromberg CD 150/175 carbs are highly adjustable, and as long as fuel atomisation is not biased between cylinders by poor adaptors or manifolding, they work fine on any engine. 5, 4, 4. Fuel starvation. Black and wet. A rotary valve - effectively a long, plain-shanked screw with a slot in it, controls metering. It's easy to check, just disconnect the pumps one at Fuel starvation would normally show up when running at sustained high power, e. Now all seems well until 60mph, when it appears I have fuel starvation. Fuel consumption went up from 45mpg to 68 mpg so the conversion from twin 32mm carbs paid for itself. 5 Snatch engine problems Land Rover V8 SU carb 3. Top. Dash pots are filled with SU carb oil to within 1/2" of the top. For SU fuel I have also run a stock mechanical TR-6 fuel pump on a bored out and modified with high compression and 3/4 race camshaft TR-6 engine running three 2" SU carbs with rich needles in top gear with no signs of fuel starvation. The SU Carburetter Company. 46 sq inches. Since the needle is tapered this allows more fuel to flow past and into the engine . Mar 7 Solution #1: A low float level will create fuel starvation, which will cause the engine to stumble. Brooklyn, NY, USA I will now do a few SU carb sets/month, but with my preference being to do specialty SU work. I changed them both and sure enough, the car runs GREAT. Beatrice Shilling Miss Shilling's orifice was a very simple technical device created to counter engine cut-outs experienced during negative G manoeuvres in early Spitfire and Hurricane fighter aeroplanes during the Battle of Britain. The gap between the lever and the face of the lid should be between 0. When you pull the choke on it moves the main jet away from the needle. bang,, vrroom. SU HS2 carbs and fuel Would the fuel starvation be obvious if too low (cutting out until the bowl I had the same problem on my E-Type at higher rpms. By paul connor March 7, 2015 in British Vehicles. Covers L-Type, LCS, 300/400/500 series, and compact 200 series fuel pumps. He calls it an "HIF4" on text and an "HIF44" on the The Rolls-Royce Merlin engine originally came with a direct carburettor, prone to cut-out due to fuel flooding in negative G. All of these pumps died somewhere around 75,000 to 100,000 miles, at about the same mileage that a new SU fuel pump will fail. 2141). The new owner is a member of thisforum and i think he has now changed to twin su's and the car performs much better i beleive he may add some more info if he reads this regards Steve. What carb have you got as SU would be best option . z240zdude, Your description looks good but here is my $0. LanceLyon Jedi Hopeful. Replaced fuel separator and fuel pump but the car sometimes just starves fuel while driving and then shuts off. Back to the front carb - turn the mixture screw toward lean until the idle starts to stumble then back toward rich just enough to smooth the idle. 26 posts 1; 2; Next; GaRoadsterRookie Site Supporter Posts: 117 Joined: Mon Jul 11, 2011 7:20 pm Location: Sharpsburg, GA. etclet off the gas and in a second or 2 Sounds definitely fuel starvation and not electrics. – scott64FHC danville, United States –Posted using Jag-lovers JagFORUM Just a question that has been plagueing me for about 15 or so years. (a) If the flow is normal, examine the carburetter for obstructed float chamber needle seating or gummed needle SU FUEL PUMPS 101 by Dave DuBois First of all, a brief history of the SU Fuel pump. I can press on the gas all the way to the floor, the carbs cough, then the car picks back up - and runs well, as if no starvation issue exists. It turned out the SU carbs were leaning out at higher rpms resulting in fuel starvation. Replies 57 Views 3,908. Just google Adjusting an su carb and find: Baseline and initial adjustment, 27. See the article, SU Fuel Pumps Facts and Myths in the SU So I've followed the forum and fitted HUCO FUEL PUMP ELECTRIC SUCTION HUCO 133010 ENGINE BAY FITMENT. Hero Member; fuel starvation is a possibility or maybe a vacuum leak. Fuel drains out of pump back into fuel line. Mar 1, 2004 Re: Fuel starvation issue - 68 1600 SU Carb Setup Post by DivinDave » Fri May 29, 2015 2:33 am I cleaned out the fuel lines by first spraying some carb or parts cleaner in at the engine end, let it sit awhile and blow out with compressed air. bjhines, That is pretty close to what I recommend. The smartest move for my Atlas was dumping the twin carbs for a bigger single Concentric. Fuel: Sump screen new clean, checked and re-checked, new SU pump (pumps 2X spec. BURLEN; SU; AMAL; ZENITH; AUSTIN PEDAL CARS; SKINNERS UNION CLOTHING; TEL +44 (0)1722 412 500 1 Inadequate or no fuel supply to the AED: 1 Slacken the filter plug on the AED. 187". 00 worth of essential fittings (discounted in the kit price) which would be required to cover almost all vehicle applications fully. Print. They are easy to tune but I had fuel starvation problem at top end as the inlets were undersized. That said, I am going to go through the steps to eliminate HD8 SU Carb Fuel Starvation Hesitation Weakener Device. ) D . Tech tips and how to's. Jump to Latest Thanks for all the useful replies. I’m hoping somebody has run into this issue before and can help out. Assuming 15 BHP you will be An SU carburetor does not depend on fuel pressure, only on fuel flow. Hi guys, having a bit of an an issue with the mgb. Jun 27, 2017 As the ignition is electronic and the coil is a quality replacement I'm now thinking fuel starvation, blockage in the fuel line/tank or fuel pump. I have digressed. The DGV is a normal twin choke carb, both chokes open simultaneously. Share I have heard of a partially blocked fuel line causing starvation, but FIXED. Blown out jets and cleaned carb with carb cleaner. Assuming some head pressure from the plastic line, stock filter on the firewall, and the three carb filters, what is a good setting for fuel pressure? 3, 3. I can now support the statement that 98% of all carburetor problems are "ELECTRICAL" Thanks to all for showing interest. Fuel starvation at high rpms in a corner can damage an engine. Of a sufficient quantity to make the pump run all the time should be detectable fairly easily. The old HF carbs had to have the float chambers set level when the carb was tilted and would still SU & Zenith-Stromberg Fuel and Carburetor Symptoms & Diagnosis Print. Air leakage interferes with the carb's ability to effectively lift the dashpot piston Engine died: Fuel Starvation Meme Fuel injection provides more power and better atomization of fuel than a carburetor, meaning you can run lower octane fuels and get the same amount of power compared to a carb running higher octane gas. With mine, any gas starvation problem at the tank would result in the pump running a lot faster than normal and the gas stop flowing. SU FUEL PUMPS 101 by Dave DuBois First of all, a brief history of the SU Fuel pump. Fuel Pressure - posted in Problems, Questions and Technical: Hi all, im fitting twin hs2 carbs and at the moment im running a hif44 but i have a faset red top electric fuel pump, so i wanted to know what pressure should it be running for the twins? I have a filter king regulator so i can alter the pressure Cheers james Mechanical Fuel Pump: Fault Diagnosis. 5 to 13 a/f ratio is good for wot. But I have the mixture control screw down as far as it can go, so I can’t make the mixture richer. Solution #2: Check your fuel pressure and adjust it to these psi ranges: 5-7 psi for Holley, Quick Fuel, AED, Willy’s, or Summit Racing; or 4-5 psi for Edelbrock or Jet. usually causes intermittent fuel starvation fuel starvation. Carb needle set too low. Previous topic - Next topic. 02. You can pick up a nice set on ebay usually for less than the cost to rebuild just one of the CDCV carbs. To check the fuel flow, disconnect the carburetter end of the fuel line and place the line into a suitable container. I have a chummy scuttle tank gravity feeding an SU carb. Started by Gus Meyjes, September 07, 2007, 15:12:46. SU carbs are perfectly happy with 2. Turned on fuel tap filled ok. Floats were adjusted with the 7/16" rod (or drill bit in my case) The fuel filter is an interesting point. No matter what the temp is outside the same problem h Were you having a fuel starvation problem that caused you to look at the pump? When I suspect a fuel problem, I disconnected the fuel line at the carbs, inserted the line into a bottle and turned the key. The spark I'd discovered my RH vented fuel cap was restricting flow of gasoline causing the bike to stop from fuel starvation. 118 valve can pump out about 40% more fuel Each Classic Mini fuel pump is tested to ensure consistent fuel delivery under various operating conditions, helping to prevent common issues such as fuel starvation or irregular running. (Pertronics and 40k coil) Good fuel pressure and volume. If you have flooding or fuel starvation issues, make sure you check out the operation of the needle and seat in the carburetor. Before attempting to start it, I drained the tank, dropped it and cleaned it out with fresh gas, but not professionally cleaned. fuel in the carburetor float chambers to prevent fuel flow and the engine is stopped by fuel starvation” . Last edit at 2013-07-18 08:23 AM by cschaefer The fuel pump should have been running briefly to ensure that the chamber is full and the fuel level can then be seen in the jet hole. Float level is the Perhaps someone can help me: I've got a 1500cc MG engine in my 1950 Austin that has a single SU AUC928 carb. but if so you may need to raise the fuel level to compensate for the temporary starvation of supply. Burned and/or sticking points - usually causes intermittent fuel starvation and stalling. my guess is that the engine will run fine, but burn more fuel. Sign in to contact. Or if I prefer he has this other Su carb available. 00 of this total kit price causing fuel starvation and fuel flooding problems when off roading on steeper inclines. 5gpm of fuel pressure and the Facet puts out less than that so you run the risk of fuel starvation. Neither level had an effect. g. The car doesn't have an SU fuel pump but rather a little square box type. 2) Descriptions of common SU pump models found on MG cars, including specifications about operating The main cause of dirt in the fuel is from residue or rust in the fuel tank. 060") hole in the underside (see pic). A Gunson shows a correct mixture. The fuel flow ensures that there is sufficient fuel present in the carburetor bowl, from which it is led into If it is leaning out at higher revs and the fuel flow is good, it may have needles that are not rich enough on the ends, as suggested check an SU chart. A SU carb'd Panhead runs best without intake leaks. I set my plug gap to . Pull the choke out a gnat's and then try the cazr again. Lifting the carb-adjust piston 1/16" shows a lean mixture. I thought So it is very possible that you are starving. Fuel starvation issue - 68 1600 SU Carb Setup. The gap between the float and the lid face should be between 0. My present 750 Commando has an SU which gives an easy 80mpg if I cruise at 50mph. Twin 'SU' and 'Stromberg' Carb System are becoming very difficult to supply or recondition effectively due to them becoming more of a Classic method of fuelling, and Gostaríamos de exibir a descriçãoaqui, mas o site que você está não nos permite. ) filter at carbs is spotless in & out. The new Amal 'Stay Up' float has stainless steel tangs which can be bent to alter the fuel level. OP. Joined Feb 21, 2010 · 659 Posts #21 Yes, I feel the car has to be lean/starving for fuel as the original post heading suggests. Normally mid/dark brown. php(1617) : eval()'d code PHP 8. The original design was a clean and simple layout in marked contrast to the multi-jet fixed choke carburetters and it provided a standard of flexibility bjhines, That is pretty close to what I recommend. We were able to get fuel pressure and run the new engine in the garage with only 3 gallons in the tank, so I feel we at least have the pick up plumbed properly. 1. reliable and very durable, given some knowledgeable maintenance and tuning. 26. Engine and carbs (UM Needles) are rebuilt valve timing is dead nuts I would recommend firstly leaving the carb already installed and try to fix the bogging down, which could be fuel starvation, definitely check fuel pump and filter. Beatrice Shilling Miss Shilling's orifice was a very simple technical device created to counter engine cut-outs Mini Starts Then Cuts Out - posted in Problems, Questions and Technical: Hey guys, I’ve recently taken my mini out of storage for the winter, I had the head fitted with bigger valves, de shrouded and ported whilst it was in storage. (just my I have replaced SU Carbs with Edelbrock Performer 500 cfm carburetor in my Range Rover Classic 1982 I hope that you purchased the Edelbrock 1791 fuel pump. Two bigger SU or Stromberg Zenith CD175 carbs can flow 530 cfm rated at 1. SU Carburetters (British spelling in honor of their country of origin!) - R. This simple system made it possible to control the amount of fuel that entered the carburetor under the different driving conditions in an efficient The bush lead terminal had a problem and the article said the motor will even show signs of fuel starvation if this is not up to snuff along with the points. xpnzc bkfrb oow dpxm abfnf iuag kdpefq fsih gcovo nnitr egm xujwk tho mdtkuze ebvvk