Quadrajet Power - Quadrajet Carburetor Disassembly & Reassembly: step by step process

We describe and walk through the disassembly of a Quadrajet carburetor and go through the process of how to install one of quadrajetpower.com's basic kit and EZ kit, then reassemble the carburetor step by step.
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quadrajetpower.com
Facebook: @quadrajetpower
Instagram: @quadrajetpower
Quadrajet parts and kits available at www.quadrajetpower.com
Items used in this video:
KITL1, complete kit specific for your Quadrajet, includes float and filter: bit.ly/39vNYrB
All kits on website: quadrajetpower.com/quadrajet-... (enter your quadrajet code number in the search bar to find kit for your carb)
Carburetor work stand: STAND bit.ly/2XaCyoa
Float measuring tool: FLTHT bit.ly/3jKUrUq
Jets: New jets quadrajetpower.com/jets/
Primary Rods: quadrajetpower.com/primary-rods/
Secondary air valve cam kit, with spring and screws: bit.ly/3hDZcgi

[@dougedwards8022]

If yall are in Texas,,,ive bought 2 of your spread bore Quadrajets. Used them on a mild built 350 in what i call rough service 😂,,,weekend off road in the hills an creek bottoms of southeast Indiana,,Switzerland county right near the Ohio river. I have to say the best bar none 4barrels ive ever had the pleasure of holding to the floor an hang on,,,never miss a lick,,,,idel is on it even at extreme inclined (sometimes to much incline no matter nose down or nose up) doesn't even matter like a hwy cruise but alot rougher an more scarey😮. Quadrajet didn't care,,same inclines engine off,,,rest bump the key right back to smooth idel ready for some more those beautiful sound of those secondarys. Mmmmm,,, thanks yall. Please keep it up

[@scottloftin1730]

I think I will need to watch this 10-15 times.

[@georgekalafatis7286]

I've been building carburetors all my life and I'm still learning

[@JoJo-11of11]

This is one of the best instructional videos on carburetors I’ve seen and I’ve been rebuilding them for over 40 years. Great for a beginner or as a refresher.

[@QuadrajetPowerLLC]

Thank you.

[@OzcarMike641]

I agree. I have never done this and I am sitting here with the carburetor and the kit, wish me luck, I am going in............

[@JoJo-11of11]

@@OzcarMike641 you’ll be fine ! Put your big boy pants on, and have a beer to relax yourself !

[@TheCanadianBubba]

Never knew about reseating the ball, usually just happy to not drop it : ] great refresh ! thanks for posting and the great commentary.

[@kevinclancy.]

your videos are such a huge help!

[@davidgoodney1509]

Thanks for the detailed video. It’s been a while since I’ve rebuilt one.

[@philliphall5198]

I’ve done thousands of them and holly 4 barrels Enjoyed it very much Happy I’m retired now

[@rowdysincoherentrambling1426]

Thank you sir! Very thorough and excellent guide.

[@burtvincent1278]

Outstanding video by an expert.

[@patrickwendling6759]

Thank you for your knowledge 💪🏽

[@MexhomieXlll]

Just got my kit from yall 💯

[@chevybob9836]

This is a great channel. Thank you for sharing.

[@tech270154]

thanks for the vid . you are more then an expert

[@onsturn]

Hello, My 69 427 Corvette with 7029215 Quadrajet dyno’d 501hp @ 5600 rpm 510 torque @ 4000 rpm. Now that it’s back in the car with 3:55 rear 4-speed it’s a dog at a rolling start. I’d thought with these numbers it would snap my neck back smoke the tires at a rolling start in 1st gear. I hear the waaaa as the secondaries open but it doesn’t put a smile on my face. The engine dyno only recorded 4000 rpm and above. The car smelled rich and after several hundred miles I pulled the plugs they were all very sooty. I installed an AFR gauge which did show lean at idle 16.5 and rich at highway cruising 13.3 and WOT was high 12s low 13s as rpms increased. I took the 74 main jets out put in 73’s. Now highway cruising is leaner high 14s low 15s but idle is even leaner 18s. I tried turning mixture screws counter clockwise but I cannot richen the mixture. Is there a way to adjust the APT on this older 69 Quadrajet or maybe I need shorter primary rods to richen the idle? I currently have 45b primary rods and AK secondary rods. Engine timing is 36 degrees. Any help would be much appreciated. Thank You Michael in N.J.

[@MilwaukeeMarv]

Open up the idle tubes .039 and Idle down channel to .060 and also the idle bypass air holes to about .106 mixture screws to .99

[@StopTheRust]

thank you for making this video.

[@buckthrusthorn1104]

Made rebuilding my carb easy! Thanks!

[@jucedcustoms2274]

Great video! Just put in our order.

[@keepitreal5148]

Finally a quadrajet rebuild video all I've seen are the dual

[@TheSifting80]

Thanks for the great video

[@gearhead0800]

Hello Marc, Very well done with one of the best Presentations that I have seen on KZbin. I thought that I was the only "nut" to clean machinery in that detail. Keep up the great work God Bless and have fun.

[@QuadrajetPowerLLC]

Glad you enjoyed it!

[@bradyzion8041]

instablaster

[@GarthThomson]

That’s the cleanest Quadrajet I’ve ever seen 👍

[@QuadrajetPowerLLC]

Thanks 👍

[@The_BIG_salad]

I'll definitely be contacting you guys within the next few months for a complete rebuild on the q-jet off my 67 Electra.

[@heat19721]

Awesome 👌 👏, Great video, 3yesr old can do it now. Just done mine 76. C10 454 💥 💥

[@QuadrajetPowerLLC]

Thanks 👍

[@rso2965]

Awesome video, thank you. I've got the same carb off my 74 Chevy C10, where the fuel filter screws in had damaged threads that someone helicoiled which also just failed. Is there anyway to fix it or is it toast??

[@1SixpenceFan]

I've driven around 20K laps in a circle track car with a quadrajet. There were only maybe six times that the carburetor gave any problems. 99% of the time, it ran flawlessly.

[@Louisianawhips]

I really need my carburetor rebuilt for my 1978 Chevy Monte Carlo 2bbl carb. Do you rebuild them for customers because I couldn’t never do it myself.

[@gorillahumpr]

Thanks for the video. I have very mild shaft play on the primaries. If you suggest me installing new bushings I know where to pay my respects forward. Please advise. Thanks

[@QuadrajetPowerLLC]

We put bushings in all primary shafts we do. It is a permanent fix.

[@truthhurts2149]

My quadrajet had a weird looking needle. Was hexagon with flat rubber seat on it. Can i replace it with one in the rebuild kit like regular needle shape.

[@Coodeville]

Do you repair the inlet threads?

[@divine4225]

How do I put the spring back on the power piston assembly

[@ourkid2000]

Great video! Are there many differences between this carburetor and the earlier 1966 style ones or is it just about the same?

[@diotribe]

Does this work/fit a 17081273 carby? off an 81, 301 V8 Turbo Trans am

[@RSTurbo323]

What did you use to clean the carb?

[@amadeo3844]

You mentioned the well plugs on models after 67 usually don’t leak. I’ve got a 7042202 (‘72 Chevy) that was just rebuilt 600 miles ago and leaves fuel on the back of my intake after a drive. Could it be anything else beside the well plugs if they weren’t sealed with marine epoxy? Thanks for this video!

[@QuadrajetPowerLLC]

Could be fuel boiling over after shut down from heat. Easy way to test your well plugs is to put carb on bench with fuel in it and let it sit overnight. Put a piece of paper under it so you can see if it leaked any.

[@Mooseracks]

My rochester / engine is running rich... had carb rebuilt / kit installed...but when trying to tune the engine...you have to keep the choke plate semi closed to get the engine to run decent... Tried adjusting the fuel/air needles...backing them out...no difference... Any thoughts is appreciated Cheers

[@QuadrajetPowerLLC]

Closing choke richens the mixture, so your carb sounds like it is lean in the set up for idle. What is the carb code number and engine specifics?

[@marcgucciardo1942]

That quaddy looks brand new. J

[@koopa816mj1]

Well I hit the pin for arm in to far. Now how do I get it back in ?

[@josephsauceda9454]

For the power piston I still have the clip that holds it in place should I reuse that or change it out for the plastic piece you gave me.

[@QuadrajetPowerLLC]

Use the clip if it has one. That is early style and it can't use the plastic retainer

[@mrlastname3065]

Looking at just the base plate --between the primary throttle bores & directly in the middle between the idle mixture screws is something that nessels itself kinda up in a hole on the main body. Is this 'thing' supposed to move any?

[@QuadrajetPowerLLC]

That is the APT screw, or Adjustable Part Throttle. The metal cap in front of the base covers the screw tip. This adjust the power piston stop, which will vary the mixture at part throttle cruising. These screws were set at factory, specific height for engine and vehicle. These screws in the base are very difficult to get loose to make them adjustable. It is possible, but difficult.

[@kyleives8510]

Hi thank you for the great video. I see on your website I have to plug in my code on my quadrajet carburetor. I have a 17085213. Will the QB1 work for that?

[@jtp682]

Very good video! I need some advice on something. I recently bought an 1986 chevy truck with a V6 4.3. It has a propane system on it and the original carburetor is no where to be found. I have a 78 quadrajet that I just rebuilt and would like to install it. the truck intake manifold is the original four barrel spreadbore quadrajet carburetor set up. Also this engine has the electronic spark control distributor without the vaccum advance. if I put this 78 carb I got on it do you think it will work just fine?

[@QuadrajetPowerLLC]

If the truck has the computer control system, the carb you use needs to have the TPS and MCS to operate properly

[@ShawnKelso-xq4ki]

I liked your Quadrajet rebuild V. I have a 1988 GMC 3500 M.H.454 R.Q.17085000 04 07 JLY. It is 800 CFM.I NEED NEW BASE W/Buterfly/front air/fuel mix.screws.Also it has a x-tra spring&jet

[@georgekalafatis7286]

Can you drill out the 4 bbl squirt noz in the air horn in 1705 chev if you need more

[@QuadrajetPowerLLC]

Yes, you can drill out the accelerator pump nozzles, but don't go too big on them.

[@onsturn]

I know secondary hangers have different letters but could you explain why I would use one over the other? Thank You

[@QuadrajetPowerLLC]

Hanger letter indicates how high the rods are hung. A for example would be higher than Z. You can change hangers to fine tune the secondary initial delivery.

[@johndecosta1467]

Does it matter which way the clip for the float faces? & how do you determine the power piston spring ?

[@QuadrajetPowerLLC]

Yes, clip must be from float side to center of the float arm, and NOT through the holes in float arm. Power piston spring is determined by comparing to original for stock engine, or by vacuum amount produced at idle.

[@groundpounder05]

Well, I’ve got it back together. Keep your fingers crossed when I hook everything back up. This was my first carb rebuild without adult supervision. 😜

[@groundpounder05]

@Colin Mcfatridge If your girl is using IG to cheat on you then you probably deserve it. Why would you need to hack her IG???

[@2525miche]

I have a Camaro Z28 - 1984 - Trans. manual. T5 Question: When choosing a new and same Quadrajet 4BB carburetor, is it important to know if it is for a trans. auto. or manual??

[@QuadrajetPowerLLC]

That isn’t as important as starting with one that was originally designed for your engine.

[@nashvilleoutlaw]

4:58 how would you get that power piston assembly out if it's completely seized? I have one that broke the whole part that sticks up because it's completely seized stuck. Drill it?

[@QuadrajetPowerLLC]

If it is an early unit, 1975 or earlier, turn it over and use a punch to push it out through the hole in main body. Put some silicone lube in hole first.

[@kellybergin1532]

Where does that little spring or clip that looks like a small paper clip go???

[@morganbrantley9058]

Please help me, going crazy. My jet stage 2 quadrajet keeps leaking fuel out of lower idle air bleed on choke side. Idles perfect, runs perfect, but after run and shut off leaky fuel causes hard start. I took throttle body off, top plate off, topped fuel to level point, and u can watch fuel just running out of lower air,fuel bleed on one side of primary. Wtf ? Lol !!

[@georgekalafatis7286]

What about replacing the plugs or resealing the bowl for leaks

[@QuadrajetPowerLLC]

1965-1967 units had pressed in plugs that can be replaced by pulling them, tapping and inserting set screws. quadrajetpower.com/well-plug-tap-and-plugs/

[@jeffokriya3389]

I was hoping to see the detail of the lil wire on top of the needle . . don´t know how to put it back, how does it attach ?

[@markmcdermott8307]

it is in the center of that tab on the float, not in the holes. It just sits in the middle.

[@barberboy9383]

84 lesabre with a 307 my quadajet was cleaned but not rebuilt i have a high idle tried a few things still nothing i was told its something inside the carb i want to rebuild it but never touched one should i send it in?

[@QuadrajetPowerLLC]

check for vacuum leaks first. "Cleaned but not rebuilt"? Did you just clean the outside and didn't disassemble?

[@oldsguy354]

Maybe someone can help me with a problem I'm having with my M4MC on a 79 Olds 403. I have fuel puddling in the choke actuator well. I can dry it out with a couple q tips, start it up and fuel gets right back in. The smell of raw fuel is quite noticeable, especially after shutting it off. At restart it acts like it's partially flooded and I have to throttle it fairly hard to clear it. The carburetor is a reman from National Carburetor in Jacksonville. It's been on the engine 2 years and has about 1000 miles on it. It did run well when i first installed it. I suspect the air horn gasket is allowing fuel to leak over the wall in the body, the body has a small crack of some kind, or the float or needle are allowing excess fuel in. There are no external fuel leaks on the carburetor. I'm not a pro, but I've been around Quadrajets my whole life and I've never seen fuel standing in the choke actuator well before. Any suggestions will be appreciated before I start throwing money and parts at it. Thanks in advance:)

[@aztecahernandez6539]

My air horn gasket is getting wet. I heard in a video you sell a thicker gasket. Also do you sell a bigger check ball, when installing the check ball I freaking GORILLA TAP IT and it got stuck, luckly got it out with some thin screw drivers. Let me know wich gasket to order. Thankx.

[@QuadrajetPowerLLC]

Hi. Go to our website and enter your quadrajet code number in the search bar. That should pull up the correct gasket for you.

[@rollin19]

When I open up my primaries fully,my secondaries are opened at 80 degrees. I watched powernation do a rebuild on the quadrajet and they said the secondaries should be at 90 degrees open at full throttle. Should it be adjusted,and how do you do that?

[@QuadrajetPowerLLC]

For max performance, they should be to 90 degree. I will put that on my video list to do

[@theungoliant9410]

No a. Pump rebuild?

[@franciscotrujillo4961]

hello friend, one question, do the primary jets and primary needles wear out? Greetings, you send to Spain, I think that on your page it does not leave ...

[@QuadrajetPowerLLC]

Yes, they will wear. Brass is soft and the tip rubs against the jet.

[@franciscotrujillo4961]

@@QuadrajetPowerLLC thank you

[@bruceallan8548]

how do you set the fast idle cam adjustment?

[@QuadrajetPowerLLC]

fast idle speed adjustment screw is under the fast idle cam. I will do a video soon and post that. Thank you.

[@franciscotrujillo4961]

One more question friend, I'll tell you, I have a Rochester Quadrajet carburetor and I want to change the primary nozzles along with the primary needles, and since there are different numbers of nozzles and primary needles, I have to deduce that depending on the number of nozzles, I must set the needle number equal to the nozzle number? I mean, if I put number 0.72 primary nozzles, should I put number 0.72 primary needles? I understand that in this way, the idling engine has the primary nozzles blocked with the primary needles, since they are of the same diameter, and that when accelerating and losing vacuum, the primary needles begin to rise, allowing fuel to pass to the primary jets, is that correct? all the best

[@QuadrajetPowerLLC]

Primary rods are typically about 30 smaller than the jets.

[@georgekalafatis7286]

Is it true to get it a little bit cleaner you can use baking soda to sandblast with and it won't hurt nothing

[@QuadrajetPowerLLC]

We have a special soda blaster that we use. It will clean things up nice with a lower pressure.

[@daisy8luke]

Near the end you say to make sure and soak it well. Soak it well in what?

[@QuadrajetPowerLLC]

We soak in a carb cleaner as one of our cleaning processes.

[@smallenginerepair7921]

I pulled my quadrajet apart and in the process when I pulled the power piston out the return spring is missing? Do I need to get another one or is it fine to operate without that spring? Carberator is a 17059286

[@QuadrajetPowerLLC]

You do need the power piston return spring.

[@smallenginerepair7921]

@@QuadrajetPowerLLC I just ordered a rebuild kit and power piston return springs from y’all’s website I wasn’t sure which one I needed so I got a light spring and a medium spring which one should I use thank you!!

[@georgekalafatis7286]

Can I buy parts from you guys also like the bushing kit for the throttle plate

[@QuadrajetPowerLLC]

Yes, go to www.quadrajetpower.com

[@franciscotrujillo4961]

que medida es la altura correcta del flotador en pulgadas? un saludo, no se si ese puede ser el problema de mi carburador

[@QuadrajetPowerLLC]

9/32" es un buen promedio

[@franciscotrujillo4961]

@@QuadrajetPowerLLC gracias

[@nigvause7630]

Hi. I have 2 questions if thats ok. First, do you supply kits for the different quadrajet carbs as mine lookks slightly different, and second, do you ship to uk (or have a dealer in europe that I can buy from. I love your breakdown, I am an Engineer and just wish to get the right kit or establish that I have a genuine Rochester Quadrajet. Thank you so much. Nigel, NV Engineering, England.

[@QuadrajetPowerLLC]

Yes, we have kits for any quadrajet. We ship outside of US through our ebay store.

[@marcoscardenas4230]

What if you do see light between the body and the base after tightening down the three screws?

[@ryangutierrez1051]

You have to be tightening down onto something?

[@GMAC1149]

I have the same question. If you see light between the body and base. What’s the corrective action to take to seal it ?

[@lennycoluccio9129]

Hello are the olds455 quadrajet able to be calibrated for camshaft thanks

[@QuadrajetPowerLLC]

Yes. Quadrajets can be tuned for any engine application

[@QuadrajetPowerLLC]

yes

[@williamdean6034]

So I have a 7043251 and I was looking for parts because i bought one that was missing parts and I can't seem to find it on your website do yall have parts for this carb?

[@QuadrajetPowerLLC]

yes we do. What parts are you looking for? Enter your quadrajet code number in our search bar.

[@williamdean6034]

@Quadrajet Power LLC I wish you could see it cause I'm not super experienced but it's mostly primary and secondary rods and choke linkages and then a rebuild kit and I believe that is it

[@QuadrajetPowerLLC]

@@williamdean6034 send pictures to [e-mail]

[@ourlordbobross3527]

My needle and seat assembly are different mine doesn't have notches in it

[@QuadrajetPowerLLC]

Very early quadrajets 1965-1967 had a drop in seat with 2 screws to hold it in. If your quadrajet is later than that, a commercial reman company may have drilled out the threads and pressed in a seat. If that is the case, the body probably has other issues as well and may need replaced.

[@henrique4361]

thanks. what is the web name place for order kit?

[@QuadrajetPowerLLC]

www.quadrajetpower.com

[@musclesquares242]

I have a little bearing in mine and i cant find where it goes

[@65metal]

It is the check ball for the throttle pump, it goes in the hole between the throttle pump and the throttle jet assembly. It prevents the fuel from returning so there is a supply of fuel readily available when you press the accelerator.

[@reginaldallen4875]

I have the same carburetor but I can't find a flot cover can you help me please

[@QuadrajetPowerLLC]

Hi, we don’t have any spare float covers left. They are not reproduced and getting harder to find.

[@S4flynlow]

Buy a junk carb for parts from a swap meet or eBay.

[@dantheman1998]

is the kit E85 safe?

[@QuadrajetPowerLLC]

Yes, everything we sell is.

[@Coodeville]

How do you repair a leaking fuel inlet?

[@QuadrajetPowerLLC]

First, try a new gasket for the filter housing. Get our good quality gaskets not the thin cheap ones from a parts store. What year is your carb?

[@Coodeville]

@@QuadrajetPowerLLC 1973 Cadillac Commercial Chassis - Miller Meteor 3 Way

[@QuadrajetPowerLLC]

@@Coodeville This is the gasket you need: quadrajetpower.com/fuel-inlet-fitting-gasket-72-and-later-nylon-style/

[@Coodeville]

@@QuadrajetPowerLLC i tried buying a few things and you're site is telling me my credit card is no good. I don't have Paypal anymore

[@Coodeville]

Now for some reason it worked. All last night it was being rejected

[@scottolisar456]

What is the best product to soak , clean the body ? We used to use a nasty product in a metal pail and basket . I’m sure that’s illegal now !

[@QuadrajetPowerLLC]

Today, we use a carb soak for all the parts and body. Soak 12 hours and rinse, then ultrasonic clean. Then we will lightly blast before color. Not many good options these days.

[@scottolisar456]

@@QuadrajetPowerLLC I read that Pinesol is a good soaker but be careful . I guess it’s more powerful than you think ?

[@QuadrajetPowerLLC]

@@scottolisar456 It will destroy the body and air horn. The internet will tell you a million different ways to clean them. I only go by what I have used and trust, and what I have seen others use. We had a body and air horn sent to us that was cleaned in Pinesol. It has holes eaten completely through the air horn. It broke down the material. You can use spray carb cleaner or brake cleaner.

[@scottolisar456]

@@QuadrajetPowerLLC thats good enough for me .

[@damnflinks]

I just wanted to say thank you. I've wanted to learn how to this since I was a kid. Finally had the chance and found this video. Thank you for sharing!

[@joelcooks2093]

How much do you charge for a rebuild

[@QuadrajetPowerLLC]

Complete rebuild starts at $350 plus shipping. We have several options depending on needs. quadrajetpower.com/quadrajet-rebuild-service/

[@ShawnKelso-xq4ki]

How do I get phone # so I can get TY some info/& buy some parts

[@QuadrajetPowerLLC]

email us at [e-mail]

[@derrickpotter3909]

Only thing I wish for the video is a quick camera shot of each part. I’m literally building this Quadra jet as I’m watching the video and it’s hard to see exactly what piece goes to what. Thanks for the video though

[@andylappin4801]

What about the jets?.

[@Avenged188ify]

Right?

[@williamb454]

U rebuild them?

[@QuadrajetPowerLLC]

Yes. www.quadrajetpower.com

[@williamb454]

@@QuadrajetPowerLLC I rebuilt mine ,using your parts,and it runs super rich! 19 inches of vacuum too, 23 weeks ?? How much does it cost??

[@trevorbullock6000]

Son of a bitch! I never thought of hammering the check ball in place.

[@conradpons9238]

I don't have a computer, what State are y'all in? And do you have a phone number to call. I have a 67,Cadillac in need of a quadrajet rebuild or rebuild kit. I'm old school so phone number or address works for me. Good information y'all have. Thanks ✌👍😃

[@williammartin4648]

I pulled the base and there were two gaskets. One atop the other. I have two in the kit. Is that right? Do i put both on? Thanks.

[@QuadrajetPowerLLC]

You should only use one gasket. If the kit has two, chose the correct one for your application.

[@conradpons9238]

I don't have a computer, what State are y'all in? And do you have a phone number to call. I have a 67,Cadillac in need of a quadrajet rebuild or rebuild kit. I'm old school so phone number or address works for me. Good information y'all have. Thanks ✌👍😃

[@superduty4556]

How did you post on KZbin without a computer? Your phone is a computer.