The distributor advance may not be working correctly. Start by increasing the fuel nozzle size up by three sizes. Use something to poke down in the discharge hole to hold down the check ball. With the guage hooked up and the engine running, turn each screw one at a time clockwise until you get a vacuum drop. Weve seen this work very well. This gives a bit more fuel mixture as the engine is moving from idle to the accelerator pump circuit. I got mine at advance auto parts for $45.00 I think it was, thats all new internal gaskets,base plate . you overlooked the holley! Carb: edelbrock performer series 600 cfm electric choke (1407). other then the instant start-up idle weirdness it idles just fine. Another thing, get a vacuum guage to tune your mixture screws with. Dan Sanchez So first, before you do anything and since this engine is new to you, do yourself a favor and remove all of the spark plugs and perform a compression check. I have also re adjusted the timing to 34 deg total advance. Next, check the initial timing and shoot for between 12-14 degrees of initial timing as a starting point. Well without knowing the op's whole here goes. The ball will most likely come out. Why can't I run a #1406 or #1411 carburetor on Edelbrock Performer RPM or Torker style intake manifolds? The linkage should move and squirt a small amount of . Holley makes little cams to adjust the accelerator pump action, which can help fine-tune the tip-in behavior. Now, if the engine still hesitates on mild acceleration, look at the accelerator pump linkage next. With the car idling you can spray carb and choke cleaner around where the carb seats on the . What are your AFR Targets set to? 1970 - Time for New Sheet Metal and an RS Conversion Kit. Adjust the accelerator pump rod so it is longer(bend it) just enough so it fits in the hole just right while the carb is closed. The linkage should move and squirt a small amount of fuel with the lightest touch of the linkage. Rhansen. https://forums.edelbrock.com/filedat?photoid=42773, If this is your first visit, be sure to We transferred the new Edelbrock intake and carb to the new engine. Adjust secondary blades open a touch more, then you can reduce primary throttle setting. The Fora platform includes forum software by XenForo. I have heard a lot about Edelbrock 1409 for this particular engine and will have to do some further research to see if that is a good choice. Dec 14, 2001. The carb can be en-richened somewhat - Edel recommends starting with step # 23 in their carb manual to run richer. Was wondering if anyone has any ideas on what could be causing this. It has a flat spot/hesitation before taking off. Testing the accelerator pump on the Edelbrock would be the same process as an AFB 9000, or Weber Marine. I've tried messing with the accel pump shot but going up or . Eldon, Missouri 65026 . Initial is like 20, advance all in right at 3000 w 36 deg. Generally I run those at all the way in then 2.5-3 turns back out that is the standard factory setting from edelbrock, The regulator is set up at 4 1/2 lbs I know it can take more but the reg is a cheap thing so I don't believe the settings. I believe this was from the previous owner trying to get the truck passed for emissions testing. Makes a poping or pinging sound not a real loud backfire. Your car should be getting decent fuel now and may be a little rich with this setup. The well is tapered and also the pump cup may not be swelled up yet. The purpose of the accelerator pump . 10 positive effects of population growth on economic development stock exhaust manifolds. So 1/2 the vac at idle would be the spring range.when i get home from work, im going over there and we will try it.. yes..the 1405 is mechanical choke and the 1406 is electric choke, http://www.edelbrock.com/automotive_new/mc/carbs_acc/performer.shtml, (You must log in or sign up to reply here. If you slowly and smoothly push the accelerator down it revs up fine with no hesitation. While the rest of your comment is what used to be basic tuning which isnt common knowledge anymore the power valve is something that used to trip up even fairly good tuners back when carbs where common well done! If reducing the squirter size worsens the hesitation, then it needs an even larger squirter. Since 2003, Jeff has held various positions at Car Craft (including editor), has written books on small block Chevy performance, and even cultivated an impressive collection of 1965 and 1966 Chevelles. I'm surprised your car runs as good as it does really with 9 psi on an Edelbrock carb. Next, check the spark plug wires. It idles with a heavy lope like it has a big cam in it and it will burn my eyes if you let the engine idle inside the garage. That makes good sense. For a better experience, please enable JavaScript in your browser before proceeding. Good deal! Insert the accelerator pump and push it to the bottom. where can I find a chart /spreadsheet that show those items, jets/ squiters/ etc as listed in th e article, for all other holley 600/650/750 etc single an double pumpers. The "Bog" simply means the engine is not receiving enough fuel when you go to wide open throttle. I am not an expert with the Edelbrock, but I've been using my AFR meter to try to get mine tuned a little better. How about the air/fuel screws? and close the primaries back to where they need to be.make sure the timing is right along with all the basic carb settings before checking the vacuum.it will probably drive ya nuts til you get it calmed down but keep trying. When you purchase through links on our site, we may earn an affiliate commission, which supports our community. If your secondaries are opening . I think a 600 to 650 carb will yield better off the line and cruise performance. I would think in the area of 650-700 cfm might work better. Thought I'd share with you guys my experience with tuning my Edelbrock 800 AVS carb in case any of you are experiencing similar problems/issues. There is no way to fix it at that point. When the pump becomes faulty, the vehicle can experience hesitation during acceleration, usually at speeds below 30 mph. Next test is to see if the discharge check is working. Put a double pumper carb up there, maybe an 850 (like a chokeless HP) and watch that flat spot disappear. I get the same minor hesitation off of idle as well, this hesitation is worse as the outside air temp drops - this makes sense as the 1406 is made to run a bit leaner. 3) Faulty Fuel System. Changing the rods and springs are very easy. A forum community dedicated to hot rod owners and enthusiasts. Usually a stumble like your describing is a lean stumble . Don't try to tune your idle with the O2, it won't be accurate. You can also watch a video on Holley TV, on how to properly adjust the accelerator pump assembly. There may be a restriction in the passage. Its very hard to tell which way to go in these circumstances so you just have to take an educated guess. Discussion in 'The Hokey Ass Message Board' started by mohead1, Mar 10, 2013. That's the very reason I switched. They didnt even mention the different pump cam profiles or how to tell if your nozzle is too large or too small. Tuning a Edelbrock AVS2 carburetor . Also the floats in the carb were moving freely. In addition to this lack of power, a vacuum leak can also cause the engine to idle roughly or even stall. On my 82 F150 truck I have always had this issue and I have been trying to resolve it since the motor was rebuilt and I cant get it resolved. Privacy Policy. check out the. Krawk101 8 mo. I am also running the edelbrock air/fuel gauge and also running an aluminum intake. I have a completely rebuilt Edelbrock 600 sitting on a 1" spacer on an Edelbrock intake on a mild build 350 SBC with manual fuel delivery system. After re-reading your initial post, I believe you need a bigger carb. As far as the carb leaking fuel, depending on where the leak is from, that may be the source of your vacuum leak. For rubber cup pumps, apply a dab of lithium grease to the cup. This paragraph applies to an instantaneous bog, hesitation, or stumble upon acceleration. Then drop the idle speed to where you want it to idle in RPM and . Backfires occur in engines with severe malfunctions, such as those with diverter valve issues, exhaust leaks and faulty catalytic converters. The goal is to deliver the right amount of fuel at the right time. Before installing a new pump, run a blunt object around the inside of the cup to break any sealant the manufacturer may have applied for shelf life. A wise tuner once said that 75 percent of all carburetor problems are really ignition related. VerticalScope Inc., 111 Peter Street, Suite 600, Toronto, Ontario, M5V 2H1, Canada. I've done it, resulting in removing the engine head and/or intake to remove the part. It shouldn't take much to pump the fluid through the passage. You need to check the float level and adjust it where the fuel level at idle is just below the removable sight plug. Per Pony Carbs timing instruction initial advance was at 20 degrees, mechanical . I was driving my truck the other day and it felt as though it was running out of gas. And that is measured at wide open throttle using a feeler gauge. Constant hesitation is covered under "surging". Good luck, burn rubber. Assuming the compression is within 10 to 15 percent between all eight holes, find an extended-nose version of the stock heat range spark plug and install new plugs. This page was generated at 01:20 PM. Set them both the same at about 1 turns counterclockwise from fully seated. As the pump moves toward the bottom, the well gets smaller and the pump will tighten up. Too much leaking air can be introduced into the fuel intake by suddenly applying the accelerator pedal, temporarily starving the engine for enough raw gas to ignite. does edelbrock make a 2 barrel carburetor 19 3407 . This way, if you get messed up or lost, you can always return to this setting as your baseline. I am fairly new at this, have not done it in years! Today's gas has very little lubricant causing premature pump failure. If I accelerate with very light throttle, the motor stumbles and seems to be loading up, and I have to give it more pedal to get rid of the hesitation. The Edelbrock system I believe is a narrow band system. William As the pump moves up to the top of the well, fuel spills over into the well under the accelerator pump. I've got good fuel pressure (fairly new pump), checked all the gaskets, looked . J.P. Jeff Smith: J.P., we can definitely help you. It will eventually expand to fit. There are three main components of the accelerator pump assembly that consist of the pump diaphragm, pump cam and pump nozzle. Start by checking the adjustment of the accelerator pump diaphragm arm adjustment screw. Let me know how it runs. Carburetor Hesitation Upon Acceleration. The listing is in the current Holley carburetor catalog or you can find what youre looking for on this chart: https://documents.holley.com/techlibrary_carb_numerical_listing.pdf. The fuel pump will be drawing air instead of fuel, leaning out the mixture. I have some ideas, either the carb (edelbrock 650cfm) is screwing . New edelbrock carb bogs & surges at wot. Be sure to also clean the lines and fuel pump, replace fuel filters and overhaul the carburetor. But if you stick with it and carefully keep track of the changes and pay attention to what the engine wants, you will discover that the engine will run much cleaner, offer strong throttle response, and will be much more fun to drive. 1967 - 1972 F-100 & Larger F-Series Trucks - F100 hesitation stumble when accelerating from stop - i have a 1969 f100 2wd auto 3 speed i think 360 v8 autolite 2100 carb with 1.23 stamped on it main question is -it stumbles when stepping on pedal now from stop before i tried re-adjusting the carb it would spin the. After graduating from Iowa State University with a journalism degree in 1978, he combined his two passions: cars and writing. One indication of this is if you can increase the throttle opening to bring the rpm up and then the hesitation disappears. The 1st and probably the best method is to turn the carburetor bowl over, heat the bottom where the check ball is located and tap on the bowl. At normal cruising no backfiring. What happens is this. 302 bog/hesitation. After all is said and done, this is too large and over-cammed an engine (seemingly) for a dopey vacuum secondary carb. Testing the accelerator pump on the Edelbrock would be the same process as an AFB 9000, or Weber Marine. Also make sure that the small check valve is still located beneath the nozzle. Is it a V1 or V2 system? 204 East 15 th Street. The motor is a stock sbc 350 with a stock cam, headers and new intake. Learn how your comment data is processed. Hesitation or Engine Miss Upon Acceleration. You are using an out of date browser. Use a 0.015 feeler gauge to make sure the adjustment is correct. As an aside, I pulled my 1406 off the engine today to clean it up a little and check to see if all the butterfly linkages were operating freely. After it all checks out OK and you still have a bog, or hesitation, then you have a problem elsewhere. The small holes may be plugged. Jeff, this is a great write-up. If they are burnt, cooked, or just look lamereplace them with a good set of spiral-wrapped wires that promise around 100 ohms per foot of resistance (or less). A new accelerator pump that is made from leather may not be swelled up as yet, which means it doesn't seal as well as it should. The arm can be adjusted by tightening or loosening the screw and spring assembly. Jun 11, 2009. Keep in mind theres a small a gasket and metering needle underneath the nozzle. 04-20-2010, 09:42 AM. I should check the jets now too. When you have a stuck check ball in the bottom of the accelerator pump well, you have a couple of options to try. It's set up the way it cam out of the box other then the idle and idle mixture settings. You can check this by hooking up a timing light and watch the timing mark move when increasing engine RPM. Hello, I have kit #35770 installed on a 383 Stroker engine. I changed the step up springs in the carb to match my vacuum. Now for where I have stuff set at: fuel: 6psi. Turn that distributer counterclockwise a bit and then drive it. 2. What cfm fldo you recommend. Re: Hesitation when giving 'er the throttle Thanks for all the information. age of adaline comet. Stay up to date with the latest releases, events, promotions and more. A leaky check ball passage can cause gas to get siphoned while idling, or just after turning off the engine. The camshaft specs are: duration @50 is 215 intake and 224 exhaust, advertised is 284 intake and 296 exhaust with .470 intake lift and .490 exhaust lift, with 1.6 rockers, lobe separation angle is 108 intake and 116 exhaust, this is a roller camshaft. The overall objective is to deliver the right amount of fuel. Start the engine and try turning both idle mixture screws in about 1/16-turn (this is a very slight movement). . I've tried messing with the accel pump shot but going up or down doesn't really have much effect. Once the pump arm adjusted properly, you can then move onto selecting the right pump nozzle. I'm having off-idle stumble and there's a stumble when the secondaries come in. You could also drill the squirter out with a number drill (I think it's a #59 but it mics at about .032). Home . Also use the hole closest to the carb for the linkage. do koalas have poisonous claws. Smith began writing for Car Craft magazine in 1979 and became editor in 1984. Timing: 8 degrees advanced. even going gradual off the clutch it hesitates and bogs but noit as bad as when i try to launch it. You dont need to drill throttle plates. Your email address will not be published. 350 SBC, 1406, RPM Air Gap, 487 heads, 9.1 cr, pretty much everything else is stock except for MSD ignition. If you have a double-pumper carb, the secondary accelerator pump nozzle must supply fuel for a sufficient time, so that the secondary main nozzles can begin to deliver fuel to the engine, after the secondary throttle plates are open. Otherwise this will also cause the engine to bog. Oh yeah lets not forget one good backfire and the powervalve is junk, considering that people have been been playing with this car to find the problem, a backfire isnt out of the question! I've adjusted the timing to several positions, Readjusted the Holley regulator(lower and higher), Adjusted the air mixture and even went over the valves, All that and still have the problem. It has the adjustable secondary's. Edelbrock Carburetor . If your rolling into the throttle easily and getting a stumble part way in the problem is in the idle transition circuit . off idle under load it stumbles when you press on the gas. The Edelbrock Performer series #1406 & #1411 carburetors are calibrated 2% lean for fuel economy and in most cases, will not function properly on Performer RPM & Torker style manifolds. Hey guys I need a little help with my edelbrock 1406. I have 2 edelbrock 600s on my hot rod and it runs like a raped ape. Its a Edelbrock 1406 model. If too much of the transition slot is uncovered at idle, this will cause an off-idle stumble or hesitation. Could be the TPS. posted 09-08-2005 04:44 PM. Retains stock bore and stroke. When you purchase through links on our site, we may earn an affiliate commission, which supports our community. That should not happen. This allows maximum fuel to flow through the nozzle. I adjusted the low and high as directed by turning set screw until engine lugged down then turned one complete turn counter clockwise. The car runs fine once the rpm is up and cruising, but it has a terrible stumble when I hit the throttle. Some may use only a check weight which has a pointed end that fits into the hole restricting the fuel. And, you probably you dont even need a new carburetor. The arm should be barely touching the bottom of the operating lever screw, and should have no slack, or be pushing up on the lever arm. Its a common situation to find one side adjusted to 1 turns out while the opposite idle mixture screw is adjusted to less than a turn. Do you think I would benefit from the regulator? My set up is a muncie m20 with a 2.73 gear in the back. Comp Cam -4 hydraulic flat tappet. Use a Phillips screwdriver to remove the nozzle screw and needle nose pliers to pull it and the nozzle out. 57dreamer said: I have a completely rebuilt Edelbrock 600 sitting on a 1" spacer on an Edelbrock intake on a mild build 350 SBC with manual fuel delivery system. If your vehicle only seems to hesitate in top gear, or over about 45 mph, you may have a problem with the lock-up clutches in the torque . What should it be?^^. Nothing aggressive, just pulling off from a stop, like . Tune it with a wide band O2 sensor (Bosch 17014 $50 at autozone). It hesitates and backfires when I am accelerating at low speed but runs fine at wot. Great info, I too had to change my springs and accelerator pump shot. Have you experimented with any spacers under the carb? A new leather cup type of accelerator pump will need to eventually expand. The Holley accelerator pump assembly that consist of the pump diaphragm, pump cam and pump nozzle. Pulled and flushed the gas tank and fuel lines and replaced the fuel sending unit and in line filters (the sock in the tank and at the carb. Jeff Smith has had a passion for cars since he began working at his grandfather's gas station at the age 10. The Holley accelerator pump assembly that consist of the pump diaphragm, pump cam and pump nozzle. Any part-throttle stab is smooth. Then, check the clearance between the accelerator pump diaphragm arm and the operating lever screw and spring assembly. Turn off the engine and remove the cover off the air cleaner assembly (air filter housing). The pump arm should move down a bit when the feeler gauge blade is inserted. You dont want to deliver too much fuel too soon, or to little fuel too late. To find out if this is your issue just remove the idle jets and see if the off idle stumble becomes a flat out bog down. Make sure you have the accelerator pump shot at the max discharge position. Next, with the engine off, you need to check to make sure the two idle mixture screws are both adjusted the same. This article leaves out a bunch of detail. Push the pump down and watch it squirt gas out of the main discharge. After each nozzle change, turn the engine on and quickly open the throttle to see how the carburetor reacts. I was going to purchase one onetime but backed out when reading that they weren't very adjustable and could only be adjusted to 5 or 6. Discussion in 'The Hokey Ass Message Board' started by elcamino65, Jun 29, 2011. The engine is a 440 with headers, an Edelbrock Victor, Jr. intake, and some kind of cam. JavaScript is disabled. The Edelbrock AVS2 carb was a great choice for your 383. I have much the same engine configuration in my T-Bucket. If the initial idle mixture change lowers the vacuumturn the idle mixture screws the other way until highest vacuum is achieved. It may not display this or other websites correctly. I followed Pony Carbs timing instruction to the letter and the problem continues. Insert a 0.015 feeler gauge between the pump arm and the adjustment screw bottom. Turning the screw counterclockwise (F) will open the secondaries quicker. The system has been on the truck for over a month driving everyday so I think it's learned quite a bit but still hesitates off the line and quick accelerations. If they are way off, thats good. But I was having problems on a hot start. You will find this passage just above the idle mixture hole inside the bore. Prior to that had the Carter which i simply couldn't get tuned properly. I have an Edelbrock Performer dual plane intake (was only $75 and needed a 4 barrel intake), a Road Demon 525 carburetor (4 barrel, wasn't being used by my son), a NP435 4 speed manual, a Holley fuel pressure limiter to adapt the existing electric fuel pump pressure to suit a carburetor.