The QJet is a large 4 barrel carburetor that has a small primary side for fuel economy and good emissions and a large secondary side for good performance. 87 Mercury 150hp BlackMax full throttle bogging down and dying User Name: I have a 45 gal. Is it a fuel injected or carbureted? Could be to rich of a fuel mixture or bad float in a carbureted engine or high end needle needs adjustment. I just don't want to run too lean and blow the. I have recently developed a loss of power, or bogging at 3/4 to full throttle. 1966 Rochester Quadrajet used on 327 Chevrolet engine with manual transmission, no. Ran WOT, got halfway across the lake, and suddenly it began to bog down, a and I get a popping rattle, which I found out later was actually backfiring up through the carb. but ive always had the problem with bogging but the backfire is new also when the car is just sitting in my drive way idleing i can press the gas and a little puff. Gearing can also be a significant factor. the bike is still mechanically stock as far as i know. The goal here is to deliver enough fuel for crisp throttle response without going too rich and flooding the engine with excessive fuel. It appeared to be flooding at idle and the fuel was leaking excessively from the throttle body linkages (on both left & right side). i have a n/a 306. I bypassed the tors, cleaned carbs x3, new plugs, fresh fuel machine idles great but soon as u hit throttle or punch it, it boggs down but if u tweek the choke it responds good then bogs again seems like im not getting enough fuel carbs are spotless now. Rochester had some carburetors that were made by Carter and show the Carter designation. When I try to pump the gas as its about to die it just turns off even quicker. When ever I give it full throttle it bogs down and wants to die till I let off the throttle. Maybe a higher tone to it?. You say you replaced a diaphragm, so it sounds like you have CV type carbs? If you have CV carbs, can you see if the slides are actually going up when you open the throttle and it starts to bog? Is the bike rideable? If the rear cylinder is only heating at a low rate it sounds like that cylinder isn't burning, could be spark or fuel. This is caused by the rate that the secondaries open at. Now it will run fine until I get over 3/4 throttle, maybe even a little closer to full throttle, then it will bog down, power drops off. When the car warms up, it bogs down bad when accelerating, (back barrels are able to open but do not seem to open when accelerating. A single barrel carburetor will normally squirt a single stream; while a two or four barrel carburetor will normally squirt 2 streams. I'll probably just. It is a good carburetor for up to close to 400 horsepower. The secondary vacuum-break is modified and installed to increase the opening of the secondary air door to eliminate bogging under rapid, hard throttle conditions. If the air valve flops open too soon/too quick you will have a bog. I will give it full throttle but the bike will keep dropping speed or just hold the speed at ~65mph. I bought a used 2008 Wildfire WFH150s This scooter sat in a garage for 2 years. 5 full turns out from full in (per my shop manual). When I hit full throttle it goes for a minute then bogs like its going to stall, so then I let off a little it's ok and then I can slowly get back close to full throttle. ? just bought a boat with a 40hp outboard, it start and runs fine, it goes at low speeds fine, but as soon as i get to about 3/4-full throttle it boggs down and looses power, almost cutting out. Another post on bogging issues with the 2010 CNS V2 carb. I got the engine timed to the 6 before TDC GM spec. Had the boat out today after some work to the carbs. Quadrajet Performance Modifications Now that you've learned how the Quadrajet works, Remove the idle-mixture adjustment screws and measure the size of the hole under them. Good morning , i recently bought a 1977 johnson 55 hp engine that idles fine and is alright at low speed , but once i open it up it bogs down. Even has stock airbox and side covers. Not opening at all the car would be down on power, but still run pretty well. A couple of degrees can make a big difference in acceleration characteristics. he gave me the original carb with the bike and the newer carb thats on it now. Timing set at 18*BTDC, cam timing straight up, manifold vaccum 17psi. 2002 WRX throttle response/ bogging problem. May backfire or. The Q-jet has large secondaries so it really sucks the gas. Fuel pressure 18 psi. When I try to pump the gas as its about to die it just turns off even quicker. Quarter or part throttle acceleration is fine and acceleration once the engine is up to 3000 rpm's and over is fine; no stumbles. You may have to register before you can post: click the register link above to proceed. So to stay in the factory air/fuel ratio at full throttle, you need to stay close to the. If less than half throttle is applied, it gains RPM like normal. I added a new carb from 17mm to a 20mm for more power. what's wrong?. Moreover, when I run over 4,000 rpms for any time, the engine bogs. Carburetor Troubleshooting Guide. I had a 400 smallblock in my 79 El Camino with a 3310 (780? cfm) Holley and was getting crappy mileage and throttle response, so I put a Quadrajet on it that I rebuilt and rejetted both the main and secondaries on as well as the power valve. It bogs down past 3/4 throttle. from a dead stop, when I step on the gas, i hear air intake, and then the rpms go down and then up and then the truck responds a second or so late. Is finding parts going to be a problem here or could I just strip it. If it idles fine but it bogs down with throttle, your high speed gas jet is probably clogged. Hopefully your use of the search feature in seadooforum. They run a lot cooler when you're stuck in traffic. If this is fixed, I will upgrade my current 3 star rating. Why does my ATV bog down and die when I keep the throttle wide open? The four-wheeler runs fine at the start, if and only if, it's sat for a few days. Stage-1 Typical Application: Stock engine; For those looking to utilize a performance-upgraded Quadrajet, the Stage 2 rebuild might be just what you need. It is a good carburetor for fuel economy and still has stellar performance when required. 5 and timing is 36 @ 3000. For an otherwise stock C-body big-block Mopar, I think they are roughly at parity. It's a QuadraJet. Observe the pump jet in the carburetor, and with your hand, work the carburetor throttle to the wide-open position. Like the title says I have a 1999 Tacoma 3. I have a '14 1000 and at a ride last weekend it started cutting in and out at full throttle. The problem gets worse as you go up the clip (lean) and better when you go down (rich). As the vehicle accelerates and rpm’s begin to rise, a vacuum begins to build up inside the intake manifold. Basic Carb Adjusting Procedures/Guidelines - Timing can affect performance. willys_truck, Dec Also check for play in. The Dashpot pulls the throttle linkage shut so disconnecting it would cause the problem all the time. Aren't they supposed to open at full throttle? I'm no carb expert. Full Forum Listing. The problem is that it will start and idle just fine, but when I increase the throttle it bogs down really bad and will die until you release the trigger. 3) Replace the power valve. 1966 Rochester Quadrajet used on 327 Chevrolet engine with manual transmission, no. Ryobi CS30 bogs down when choke open I have a Ryobi CS30 trimmer that I am having some trouble with. This mainly helps out 1/4 -3/4 throttle, but it also has a small effect just off idle as well. The QJet is a large 4 barrel carburetor that has a small primary side for fuel economy and good emissions and a large secondary side for good performance. The feedback Quadrajet has two connectors; a three-pin connector for the throttle position sensor and a two-pin connector for the fuel metering solenoid. Outboard Marine Motor bogs down when giving it throttle it too would bog down when I gave it gas. Quarter or part throttle acceleration is fine and acceleration once the engine is up to 3000 rpm’s and over is fine; no stumbles. [My Mercury 50-HP FOURSTROKE outboard engine] starts and runs fine to half-throttle. Is it a fuel injected or carbureted? Could be to rich of a fuel mixture or bad float in a carbureted engine or high end needle needs adjustment. the bike seemed to be flooded from the many attempts to start it so i pull started it with my buggy. More common that secondaries that do not open fully are secondaries that open too far. The bike runs great until it warms up - and it has to be hot out (over 85 degrees). How do you get an alfursan membership form? 426 want this answered. I have: Cleaned the carb inside and out many times. Page 1 of 2 - Bog at full throttle - posted in REV Chassis - Mountain Sleds: Today at elevation(8-10 k) the sled would bog real bad at wide open throttle, but was fine at 3/4 throttle and down. At best, it will run at half throttle, but never at peak rpm. 71 chevy with 350 engine, edelbrock intake and 600 cfm carb setup, new HEI distributor put installed, 8mm spark plug wires. Ended up being the damn water pump, just something you might wanna check out. My problem comes and goes. If I try to give it any throttle at all, it bogs out and dies. i ordered a ordered a 62 main jet that i will install next week when it comes in. When the engine looses vacuum the dashpot moves out. Hi, Recently purchased a second hand 50cc Yamaha Jog CV50 (2 stroke) which has done around 11,000kms. July - Aug. It accelerates smooth, but after a few blocks at top speed, it starts to sputter, bogs, and will die unless I let go of the throttle. It does this in both neutral and all the gears, when it hits 6k, no matter how much gas u give it; it just doesnt go any further. It's been bogging out when I give it 1/2 or full throttle. Takeoff fine, easily enough power to sweep me up in a short distance, full throttle up to 1000 feet before easing off and making some gentle turns - from then on when I tried full throttle the engine would slightly 'Bog' - I think that's the technical term. Next, I have a few drips of fuel leaking from either the throttle plate, or base plate of the carb, which I think shows that I have a vacuum leak. Your polaris ATV is bogging down when you give it full throttle what is wrong and how do you fix it? Unanswered Questions. Honda snowblower backfiring on idle My Honda HS928 snowblower, now entering its sixth winter, backfires when idling, and surges a little at full throttle. Make certain that it positively closes the throttle. Possibly damaged by a backfire condition. My problem now is that after the car turns on, it will idle beautifully for about 10-15 seconds then bogs out and dies. Rochester Quadrajet carburetor parts, including carburetor kits and other parts associated to the Quadrajet carburetor. The engine bogs down. It bogs down past 3/4 throttle. I did manage to start it periodically and let it get up to operating temps, same with the genset and roof A/C's. It also has those little plastic limiter's on the carb adjustment screws. 2000 Tundra R Bogs at Full Throttle - posted in Freestyle / Legend / Tundra / Expedition Sport: Hi All, Im having a little trouble with a 2000 Tundra R. I have checked for vacuum leaks and found none. I have a huge lean bog at WOT. Power valve blown out by spitback up through carb. Possibly damaged by a backfire condition. I also had a vacuum gauge hooked up in-line between the bulb and the motor. The code of manufacture is also at this location. Ended up being the damn water pump, just something you might wanna check out. Connect the diaphram and see if the bog goes away. *Removed the carburetor, cleaned it (did not touch the float) and put back together. Its bogging out when loaded and warm, but runs fine cold: I recently got the machine as a cabin machine, when I bought it I was warned it bogged when loaded going up a hill in deep snow. I added a new carb from 17mm to a 20mm for more power. 7026203 - number is on the blue 'bottle cap' visible on the throttle side. It could also have an injector that’s sticking open. My Shindaiwa T261 weed eater is bogging down when accelerated. I am working on an MS250 right now that runs pretty well on full throttle if you can get it there. This evening placed 30's for pilots. A lean fuel condition bog is what it feels like. Quadrajet, high idle with warm engine Throttle return springs and choke unloader issues. anyone knows what the issue could be? by the way its a 1985 gti mk2. It could best be described as a rapid misfire. This book, How to Rebuild and Modify Rochester Quadrajet Carburetors, seeks to lift the veil of mystery surrounding the Q-Jet and show owners how to tune and modify their carbs for maximum performance. Hook up the throttle linkage and adjust for full throttle with someone pressing the gas pedal. I've tried holding the rev's up and pumping the gas when its about to turn off but that hasn't helped. The more I bury the throttle the more it bogs and losses power. As long as I didn't ask more then that from her she ran for three hours without fault. I have recently developed a loss of power, or bogging at 3/4 to full throttle. Trying that is by using Stihl Ultra bottles and pouring a little less but I always have some left over gas in the can So anyhow, I've ran about 25 hours and took it for a tune up. Idles and runs great with no load but as soon as we put her in the water she bogs down and loads up at just past 3/4 throttle. I have a 2007 GSXR 750 with just a slipon /SET valve removal. the car engine bogged down and almost died but within seconds the engine suddenly came to life , accelerated the car and an accident was avoided. Huge secondary bores hold the potential for massive power. I think that's the best way to put it. Hi guys, hope you can help me, once i start my On road nitro car the engine gets up to temperature about 215f and idles perfectly, when i give it full throttle it bogs down and will sometimes cut out, am i running too rich or too lean on the HSN. When starting cold, engine idles (set at 700 RPM) just fine, when engine is warmed up (5 -10 min), engage full throttle and all is good. Easy Retrieve Full Source. The unit have a compression of 150psi. Since its introduction in 1965, the Rochester Quadrajet has never received the respect it deserves. Dual Throttle Return Spring Carb Bracket Holley Edelbrock Carter Quadrajet A157 See more like this Quadrajet short fuel filter kit with spring and gasket, 72-89. Just bought a new Husqvarna 128LD. Hi all I'm new here I need some help I have a 253 in my one tonner and I just put a new quadrajet on it that i brought from bursons and it started up after I put it on and mucked arround with the choke I got it to run but it run real rich it went ok I drove up the street to get fuel and then went around the block and it started running rough and now it won't start if any one is around the. at 900 idle its on idle circuit mains start about 1100. Half to full throttle bog on 2. Generally, the telltale sign is good initial throttle response, but shortly thereafter the engine bogs down or flat lines and as the RPM climbs it recovers accelerating normally. Generally the air valve spring is adjusted between ½ to 1 full turn, after approximately 1 ¼ turns the spring life will be greatly shortened do to being over stressed. The motor has about 5000 miles on it and seems pretty solid. Maybe a higher tone to it?. Make certain that it positively closes the throttle. Gearing can also be a significant factor. Runs perfectly fine at the first 3/4 of throttle and idles. until you pass the 45 MPH point then it starts to surge and bog it will go full throttle then back down then back up. If I am attempting to pull my wife and daughter out of the water on a tube, I can't get the boat to plane. Even has stock airbox and side covers. QJ Throttle Solenoids, Dash Pots Carburetor idle stop solenoids are used to reduce idle RPM to prevent engine run-on when ignition key is turned off. com has led you here!. The problem can be cured by turning the car off, then back to II without starting for a couple of minutes before starting. The problem I am experiencing is when I floor it or nearly floor it, it has good power for a couple of seconds, then bogs down. // Power plant at full throttle sparks closure of bog rail INCREASED traffic levels on the rail network at Blackwater bog, due to increased demands from the Shannonbridge power station, are behind the decision by Bord na Mona to clos. The body is a 340, engine is a 400 free air (I can't find any. Q: Firebird Q-Jet 'Tab' for 1967 / 1968 Does anyone have information of the bent tab used to limit the horsepower for the carburetor found on the 400 Firebird. For that matter I can't even see the back lower blades open when I go full throttle. Smooth engine operation and can get full throttle to about 4200 RPM. If less than half throttle is applied, it gains RPM like normal. Wholesale RV Parts, RV Supplies, & RV Accessories for Motorhomes, Campers, Travel Trailers & 5th Wheels. Its beautiful outside today! So I'm working on a 1977 Puch Maxi 1hp. The part number is cast into the secondary side of the float bowl and needs to be referenced for rebuilt kits and high-performance tuning parts. I am working on an MS250 right now that runs pretty well on full throttle if you can get it there. I got the engine timed to the 6 before TDC GM spec. Tools for Adjusting a Rochester Quadrajet 4-Barrel Carburetor. Once that is as good as possible, go one step richer with yor secondary rods and see what happens. The leaner the rods the less quickly you can open the airvalves without it bogging. 350 with HEI and quadrajet, Stumble when full throttle It is hard to get that off idle bog out of a old quadrajet. If your carburetor has vacuum secondaries and a noticeable bog on full-throttle acceleration, the secondary spring may be too weak. 3/4 to full throttle, main jet and power jet if used. Runs fantastic except when I give it fast throttle, it bogs down. a 2mm drill bit fits easy thru the idle holes the mixture screws seat still thou so they have been drilled out. As for choke adjustment when the choke is closed and cold you want the choke butterfly closed down so there is a little gap not slammed shut. So far I have tried all the needle clip positions. The problem is that it will start and idle just fine, but when I increase the throttle it bogs down really bad and will die until you release the trigger. ive had this problem ongoing since end of last season and have tried to fix it myself but i am at a loss. This is your full blast top end circuit. Firemanmike, I too have a quadrajet that I believe is a culprit, motor starts fine, throttles up good but only getting 2200 rpms out of engine. As soon as the secondary throttle plates and air valve would open, complete bog. In addition to this circuit, there is a tiny slot cut into the throttle opening on the primary side (and on all four barrels if the carburetor is equipped with four-corner idle mixture adjustment). Had the blower out today with the throttle locked wide open and it started to bog out as if it was starving for fuel. Stage 2 OTS bogs & goes full rich at part throttle Hey, I finished the stage 2 setup on my 2004 WRX this weekend and I am now having drivability issues. - RV Parts Country. The problem gets worse as you go up the clip (lean) and better when you go down (rich). All tundras do this. The leaner the rods the less quickly you can open the airvalves without it bogging. I bought my son a brand new TaoTao 125cc ATV. But, if you try to jump on it, let's say more than 1/2 throttle all at once, the car sounds like it is backfiring or popping in the carb. The car runs fine idles rough sometimes when cold, when I hold the throttle wide open the motor will bog with no power at all. From 1976 or so until 1978, the Jeep 360 and 401 4bbl engines used a unique spreadbore carburetor known as the Motorcraft 4350. I have a Traxxas nitro sport that is running good except for one thing. From cold, closed to 1/4 throttle, choke and idle jet. Once home the fuel tank was almost empty so I filled it with 91 octane and added about 4oz of seafoam. The motor has about 5000 miles on it and seems pretty solid. No tach, so I don't know what the actual RPM is, but it sounds a little low. I took it out on the lake and even though it idles fine on land, it stumbles in the water. it hits the power band at weird times, and has to build up to its top speed and if you hit full throttle loses power. I have cleaned both carbs. It is a good carburetor for fuel economy and still has stellar performance when required. Sounds like a plan. Others who have had this low power bog problem at low rpms, have shimmmed the needles and removed the snorkel. How do you get an alfursan membership form? 426 want this answered. kept in top gear and then tried full throttle at low speeds/rpm, but I didnt really go anywhere. Bogs with Throttle opening guessing it was the three wires i must try. the bike is still mechanically stock as far as i know. Its beautiful outside today! So I'm working on a 1977 Puch Maxi 1hp. If it bogs on 1/8 to 1/4 of a turn then it was about right and you should leave it. Accelerates smoothly and with no problem. if you give it any throttle, especially if you "gun" it, it will either jump the rpms to just a little more than "idle" rpms, and then actually decrease rpms until it stalls, or if you let off the throttle it stablizes. The carburetor has been cleaned and is not clogged or anything. The more I bury the throttle the more it bogs and losses power. It's been bogging out when I give it 1/2 or full throttle. Start at 4:51 if your in a hurry for a solution. willys_truck, Dec Also check for play in. 1980 Rochester Quadrajet 4MV Bogs Down with Any Throttle I went to start it and it starts fine but bogs way down with any throttle. When ever I give it full throttle it bogs down and wants to die till I let off the throttle. This will result in a "sputter" at full throttle. Rochester Quadrajet 4 BBL Carburetor GM 17085212 0586 HPA 454 Plug-N-Play Ready. I have an extended intake pipe so should i need to adjust the fuel/air ratio because of that?. Hi I recently bought a 2000 rm125. Any more throttle, and it gains no more RPM, and after a certain point, (when I give it full throttle) it actually bogs down and loses some RPM. Idles and runs great with no load but as soon as we put her in the water she bogs down and loads up at just past 3/4 throttle. If you attempt to accelerate too hard off idle, to the point where the secondaries kick in, the car bogs and stumbles to the point where it dies unless you lift your foot off the pedal. *Snow blower started right but was leaking gas out of the carb. Stage 2 OTS bogs & goes full rich at part throttle Hey, I finished the stage 2 setup on my 2004 WRX this weekend and I am now having drivability issues. Part throttle response is great and crisp. Discussion. I've had my new bike running for two days and I've noticed if i twist the throttle all the way all at once it bogs down and wants to die. stock is 26 mm i believe, what is a good size to go to without haveing to change a lot of other things, besides boots? i just got these cuz they would have different jets in them and that would tell me if thats the. Also, once she warms up, very high/fast idle. The unit have a compression of 150psi. Q-Jet secondary throttle plates should NOT open to the full vertical position or beyond. > Subject: [GMCnet] Quadrajet problems > > > > Unfortunately we left our GMC sit pretty much unused for several years. So just a quick update: I worked on the carb for a couple of hours today. I have tried the H screw everywhere from all the way in to 5 full turns out and it still bogs and dies, tried the L screw lots of places too. Once that is as good as possible, go one step richer with yor secondary rods and see what happens. Holley carb bog at full throttle I have a small block Chevy 350 with single plane intake, Holley 750 double pumper, 50cc pump, 72 jets in the front & 73 jets in the. the guy said he had issues with it keeping an idle. Small primary bores with triple venturis offer excellent throttle response and fuel economy. The Quadrajet's large secondary venturis are controlled by a lower set of throttle plates that are opened by a progressive linkage connected to the primary throttle shaft. I have read through many of posts and tried to follow some of the troubleshooting steps that others have had success with, but to no avail. 32/36 Weber Bogs Down At Full Throttle I took it for a test drive the other day and everything is great except when applying full throttle. Timing set at 18*BTDC, cam timing straight up, manifold vaccum 17psi. New Taotao ATM50-A1 Bogs Down Under Throttle By jdlev (Read 21,903 times) Put it back in, and the same symptomshard to start and bogs down at full throttle. The thing is like new and the only thing done was that the baffle (silencer) was removed. Any more throttle, and it gains no more RPM, and after a certain point, (when I give it full throttle) it actually bogs down and loses some RPM. 71 chevy with 350 engine, edelbrock intake and 600 cfm carb setup, new HEI distributor put installed, 8mm spark plug wires. I'm not so sure this is the reason I bog out at full throttle, I doubt it. I will say that the bogging sounds different somehow from what it sounds like if it is flooding. I can get it to start and idle high. now it idles but if i give it anymore than say about 15%throttle it bogs out. with 50,000 coil i run 28 deg timing idle and 32. Search out a "book" on q-jets, they are on the web. More common that secondaries that do not open fully are secondaries that open too far. At full throttle the bike boggs down, very fast. It doesnt do it everytime i give it full throttle, but enough to really piss me off. Trying that is by using Stihl Ultra bottles and pouring a little less but I always have some left over gas in the can So anyhow, I've ran about 25 hours and took it for a tune up. it just bogs and sounds like it wants to die. Sounds like a plan. You say you replaced a diaphragm, so it sounds like you have CV type carbs? If you have CV carbs, can you see if the slides are actually going up when you open the throttle and it starts to bog? Is the bike rideable? If the rear cylinder is only heating at a low rate it sounds like that cylinder isn't burning, could be spark or fuel. Is the choke linkage adjusted properly? Is the choke opening all the way as the motor warms?. It's a QuadraJet. This gateway is completely opened while in the highest throttle. I have checked for vacuum leaks and found none. I push the accelerator and it sounds like it's flooding out or something and I've got barely enough to get up the hill. The unit have a compression of 150psi. Do you have the mixture screw set to the recommended number of turns? Have you read the "Carb Guide" that is found in the "Tech" section? There is a ton of good info in the "Tech" section to read over. It only does this at WOT, if I throttle back some, I am still up on plane, and the backfiring and bogging stops, so I don't think it is the lifters again. Just got an 08 kfx 450r the other day and am new to the injection stuff. Although most Quadrajet float levels are set at 38, the specification. (hard acceleration) As the vacuum recovers the dashpot pulls the throttle linkage shut. Quadrajet: The Rodney Dangerfield of Carburetors. I bought a used 2008 Wildfire WFH150s This scooter sat in a garage for 2 years. Your polaris ATV is bogging down when you give it full throttle what is wrong and how do you fix it? Unanswered Questions. With years of Qjet experience and hundreds of satisfied customers, our carbs are track proven and dyno tested. Anytime I switch fuels (pump gas or E85) I do a crank relearn. Runs great on flat road at minimal throttle. I'll probably just. Hook up the throttle linkage and adjust for full throttle with someone pressing the gas pedal. Power valve blown out by spitback up through carb. Go out and try a Wide Open Throttle acceleration. It is broken in, has had about about 25-20 tanks through it. Why does A CHEVY 350 engine run flawless at idle but bog and sputter at wide open throttle? Answer. My engine bogs when full throttle is applied If this is your first visit, be sure to check out the FAQ by clicking the link above. Note: a rich condition is not the only possible source of this type of problem. I have a quadrajet on the 454 in my truck, electric choke etc. Ford Ranger Forum - Forums for Ford Ranger enthusiasts! > Engine Tech Forum > 6-Cylinder Tech > 4. If your carb is a Rochester Quadrajet & bogs when the secondaries open, the secondaries are opening too fast. There are many ways this can happen, from a bad vac leak (idle control valve hoses in particular, or a loose booster vac line) to a bad fuel distributor or air flow "pot" that senses throttle opening. (This is where the "Professional Carb Rebuilder" failed when I first bought the boat. The problem gets worse as you go up the clip (lean) and better when you go down (rich). if you give it any throttle, especially if you "gun" it, it will either jump the rpms to just a little more than "idle" rpms, and then actually decrease rpms until it stalls, or if you let off the throttle it stablizes. Also, once she warms up, very high/fast idle. I'll probably just. Has a quadrajet carb, new fuel pump and filter, new points, condensor, new coil. i found some used pipes 4-1 sounds great i think the cleaner i used is causing the slides to stick or maybe the main jets are gummed up. It is also strange because if I mess with the choke enough, I can get it to blow pretty hard with half throttle (and it won't die down), but it is very hit-and-miss and still doesn't blow. Seems like 3/4 throttle is full throttle. How to Cure Carburetor Stumble May 13, 2014 Dan Sanchez Fuel Delivery , How-To and Tech Tips , News , Tech , Tech Tips 2 Cure The Bog And Sluggish Response On Your Holley Four-Barrel Carburetor By Properly Adjusting The Accelerator Pump Assembly. Juice box pro with a few different maps. 1985/86 Q-jets in U. Q: Firebird Q-Jet 'Tab' for 1967 / 1968 Does anyone have information of the bent tab used to limit the horsepower for the carburetor found on the 400 Firebird. Start at 4:51 if your in a hurry for a solution. If I let off the throttle it would come back to life and then. It starts right up within a second without choke. Spring windup should be at factory specs, at least until the bog is gone. When I accelerate my Chevy bogs down, it starts to sputter and pop, ie blow back through the TBI throat. 1971 - 1973 Corvette Brake Booster Vacuum Pipe for Quadrajet Carb. so say I'll be idling through a channel through a no wake zone and then I get back to open water. • Hook up the throttle linkage and adjust for full throttle with someone depressing the gas pedal. i oiled the uni filter with foam filter oil. 1966 Rochester Quadrajet used on 327 Chevrolet engine with manual transmission, no. However I am bogging down or not running on as well as it was when I come off full throttle. When the engine looses vacuum the dashpot moves out. The last test is the one that I want a second (or third or fourth) opinion on. Other online resources and digital media. Walbro WJ-71 ZDZ 80 RV engine ZDZ oem ignition. Q: Firebird Q-Jet 'Tab' for 1967 / 1968 Does anyone have information of the bent tab used to limit the horsepower for the carburetor found on the 400 Firebird. I have replaced the entire carb, checked the fuel lines, checked the airbox, the tube from the engine to the fuel vacuum. To start this off, I just wanted to tell a little bit about the stock Q-jet that came on my truck (1985 C-10). When I pull off slow, it pulls off fine but as soon as I put throttle on it bogs down and cuts out. When an engine won't rev up with throttle increase, it means the carbs are starving for fuel/air mixture which comes from the pilot circuit. If I keep on the throttle and wait, the bike will accelerate (slowly) then when the tach gets to 8K - it takes off like a bat out of hell!. I got this baby running, but I cant manage to make it above 20 mph. Seems like 3/4 throttle is full throttle. Maybe a higher tone to it?. It bogs down past 3/4 throttle. Clean your carb and spray carb cleaner in all small passages, make sure air can flow through all ports no matter how small.