When the choke is closed (active), the idle must be set off the fast idle cam adjustment screw. Most people don’t understand that. Good video Mark. Thank you.
Good video. I knew all this from my 79 Trans Am I tinkered with back in 85, but now I'm refreshing because I'm facing the same thing on an 87 Camaro that has a bad choke element or something, not opening all the way and causing all the related problems.
Thanks for your knowledge! I've had the opportunity to learn what to do on a couple of large Carter quad carbs. Awesome design I had a 1971 Chevy Monte Carlo with a stock 454cu in, the first run Super Sport model for the Monte Carlo.
The primary choke blade on my Rochester 17059222 has a little slop to it and it rests at about 100degree - not straight up at 90degree. It's rod wiggles too. Been trying to correct my choke action and idle after i apparently bugured it up some how. This is a one wire e- choke. The e- cover is at about 2 o'clock when it is set. The vacuum pull works at start up as does the choke itself- but at start the idle was way to high. I had to counter clockwise the screw on passenger side and this brought the excessive high idle at start up down to a reasonable level. 80outside temp. When this first happened i could not get it to step down in normal fashion by gooseing rpms But i found this post of yours. Subscribed. Thanks Any other pointers.how factory set fast idle. Suggestion - how primary choke linkages are connected and work together to smooth start these late 70's e-chokes. Thanks
Unless we are doing a correct original restoration, we typically eliminate the secondary lockout. If choke is engaged at all secondaries won’t open. Most people prefer to have them open on demand. I will make a note for a future video.
good video but it's a pity that you no longer send material to Spain, here there is no where to buy the custom kits and we can't find them anywhere else. I hope you send them again. Thank you
Do you know what the factory specs were for RPMs at the different steps on the high idle cam? I.e. Choke closed (barely open with vacuum break), what should the RPM be at? Then, with choke off/all the way open, what should the RPM be for a warmed up engine? 1984 Chevy C20 454, Quadrajet 4BBL is what I have.
I'll be honest I was considering sending you guys a Q-Jet to rebuild but then I saw where the main page on the website said 30+ week turn around. Now I'm just considering buying a reman one.
We do stay very busy. We build them right, specific for the application. Most commercial reman units are generic built and aren't able to be tuned for specific application, so be careful.
What should you do if the main idle screw does not lower the idle enough? I’m at 750 rpm on my 442 for the main idle and it won’t go down anymore. I have triple checked and there are no vacuum leaks and the car runs very well. Should you just turn the idle mixture screws in?
Make sure there isn't anything preventing the throttle blades from closing all the way. It is getting air from somewhere. Sometimes rear blades will stick open some. Also look at timing and vacuum advance, you may need a ported vacuum for advance.
Quadrajet Power LLC isn’t ported vacuum what the factory did for advance? I’m running 13-14 initial advance which is 1-2 degrees more than the factory recommended for the premium tune. The motor seems to really like a little bit more advance and is not pinging at all.
Quadrajet Power LLC I’ve never understood that. At WOT you are actually removing advance if you go manifold. Thanks for the tips. I think I am going to leave my quadrajet alone. I am idling at 700 which is the factory spec, it’s just without the idle screw touching the blades. Otherwise the carb runs great.
Good info. I didn't know before seeing this. Thanks. How/what do you set to keep the engine from stalling when coming to a stop while in "Drive" with auto trans.
@@QuadrajetPowerLLC Yes, that appears to be my problem. Bought a new float from you and installed it. Old float was "dead" and was much heavier than the new float. Installed new float and rebuilt carb. Still have to install carb on engine, adjust, and test-run the car. Will try to remember to let you know how it all turns out. Thanks again.
Good vidio, The air/ fuel mix screws say to bottom them out then turn each one out 3 to 3and 1/2 turns each to start. Where is a good start point for the fast idle screw
Do these adjustments work the other way too? I had to adjust my choke thermostat clocking and vacuum pull off a while ago, and ever since then, my fast idle is really high and stays there for a very long time (5 mins or so before finally dropping down a bit). Is it possible that, by making these adjustments, I tightened up the fast idle cam?
Just got a 86 regal with 36k miles on it. Car is prefect except for the fast idle. It's getting hung up and I'm having to flip it down some morning to get it to idle down. It's barely getting hung up. I barely touch it and it falls down. What could cause this? Any tips?
I just bought a 1970 Buick GS 455. When my choke is active the rpms are 1,000. The problem I have is, even when the engine is warm, the fast idle does not drop. When I'm in drive (TH400 Trans) tye rpms are 650 to 700 and thth's fine, but when I'm in park the rpms increase to 1,000 and when I put it in drive, I get a not so nice jerk. I have adjusted the fast and slow idle screws serveral times but can't get the fast idle to decrease. What I'm I doing wrong?
Make sure the fast idle cam moves freely, and will fall to bottom when choke isn’t engaged. Also, make sure your choke is fully released, primary flap fully open when engine is warm. You may need to adjust choke, by bending choke rod to make sure it will fully release.
Good video. All your videos have been helpful for me. Question. 1986 c20 suburban. 350, non ac truck, manual transmission. carb #17085003 The idle solenoid stays engaged keeping it at a high idle. I can’t find any info on this issue. What is the purpose of the solenoid ? I thought those were for a/c equipped rigs anyways..? What could the cause of it staying on be ? Thanks in advance for any info.
Make sure your fast idle cam follower isn’t getting hung up on anything and that your throttle cable isn’t too tight. My car had same issue, turned out to be the cam follower (piece that swings down as choke opens) on the passenger side was getting caught on something. You will not be able to use all 4 barrels unless this cam falls out of the way. Too much tension on the throttle cable can also cause your issue.
@@frankalbano7333 Thanks. I already checked both those things. It kicks down off the cold high idle correctly. No hang ups. The cable has enough slack at idle. They are definitely not the issue. It idles fine with the solenoid unhooked. Sits right on the idle adjustment screw. I can physically see the solenoid move the linkage up to a high idle when you plug it in. I’ve just unplugged it for now. It works, but I want to keep it stock and can’t find info on the purpose of the solenoid on a factory NON A/C truck.
@@frankalbano7333 That’s what I thought too. It puzzles me cause the truck is as original and stock as you’ll ever see. Factory no A/C. Very basic model. Every factory vacuum line is in place. Both smog pumps. The wiring for the solenoid is factory. As far as I can tell the only thing that had ever been changed was the rad hoses, one heater hose, filters and the fluids. I put a starter and a distributor in it. It was ordered new for Oregon DOT. The guy I bought it from drove it when he worked for the Oregon dot, and then bought it from them in 1999. He sold it to me last year with 148,000 original miles. I put 20,000 miles on it in the year I’ve owned it driving it all over the country. Maybe it was some high idle system for idling with flashing lights and radio running..? It did have those.
Hi, great video. Question: when my car is warmed up, the choke blade still is not totally vertical in the up position. What do I have to adjust? Its a Quadrajet in a Corvette 1978. Thanks!
My Quadrajet on my old pickup put it to the floor four-barrel kicks in but it doesn't really accelerating acts like it needs more gas. How do I do that
Hi, would anyone know if the fast idle screw below the fast idle cam shown in the video can be ordered and what the part # is. I lost mine. I do have the curb idle screw.
When the choke is closed (active), the idle must be set off the fast idle cam adjustment screw. Most people don’t understand that. Good video Mark. Thank you.
Thank you!
Well done.straight to the point with the carb on the bench. Din’t have to fight with camera and mirror’s to show where screws were located..
Great video, had someone out to tune my quadrajet and messed it up, after watching this was able to re tune it and drives awesome
Nice work!
Good video. I knew all this from my 79 Trans Am I tinkered with back in 85, but now I'm refreshing because I'm facing the same thing on an 87 Camaro that has a bad choke element or something, not opening all the way and causing all the related problems.
do some common trouble shooting vids on chock issues...cleaning /correcting..
Thanks for your knowledge! I've had the opportunity to learn what to do on a couple of large Carter quad carbs. Awesome design I had a 1971 Chevy Monte Carlo with a stock 454cu in, the first run Super Sport model for the Monte Carlo.
This is precisely what I needed. Thanks so much!!
Glad to help. Thank you.
thank you that was what i needed for my 85 trans am to pass the emissions test in Colorado
The primary choke blade on my Rochester 17059222 has a little slop to it and it rests at about 100degree - not straight up at 90degree.
It's rod wiggles too. Been trying to correct my choke action and idle after i apparently bugured it up some how.
This is a one wire e- choke. The e- cover is at about 2 o'clock when it is set. The vacuum pull works at start up as does the choke itself- but at start the idle was way to high. I had to counter clockwise the screw on passenger side and this brought the excessive high idle at start up down to a reasonable level. 80outside temp.
When this first happened i could not get it to step down in normal fashion by gooseing rpms
But i found this post of yours. Subscribed.
Thanks
Any other pointers.how factory set fast idle.
Suggestion - how primary choke linkages are connected and work together to smooth start these late 70's e-chokes.
Thanks
Very Helpful, would have like to have seen the secondary lockout and how that works with the fast idle cam.
Unless we are doing a correct original restoration, we typically eliminate the secondary lockout. If choke is engaged at all secondaries won’t open. Most people prefer to have them open on demand. I will make a note for a future video.
good video but it's a pity that you no longer send material to Spain, here there is no where to buy the custom kits and we can't find them anywhere else. I hope you send them again. Thank you
When car is fully warmed up and choke is off the fast idle cam doesnt go down all the way. What could cause this and how do you fix it?
Do you know what the factory specs were for RPMs at the different steps on the high idle cam? I.e. Choke closed (barely open with vacuum break), what should the RPM be at? Then, with choke off/all the way open, what should the RPM be for a warmed up engine? 1984 Chevy C20 454, Quadrajet 4BBL is what I have.
Look up your specs. For mine, a 83 350 class C. 500-700 fully warmed up. Fast idle should be around 1000-1100 rpms. Thereabouts.
I'll be honest I was considering sending you guys a Q-Jet to rebuild but then I saw where the main page on the website said 30+ week turn around. Now I'm just considering buying a reman one.
We do stay very busy. We build them right, specific for the application. Most commercial reman units are generic built and aren't able to be tuned for specific application, so be careful.
What should you do if the main idle screw does not lower the idle enough? I’m at 750 rpm on my 442 for the main idle and it won’t go down anymore. I have triple checked and there are no vacuum leaks and the car runs very well. Should you just turn the idle mixture screws in?
Make sure there isn't anything preventing the throttle blades from closing all the way. It is getting air from somewhere. Sometimes rear blades will stick open some. Also look at timing and vacuum advance, you may need a ported vacuum for advance.
Quadrajet Power LLC isn’t ported vacuum what the factory did for advance? I’m running 13-14 initial advance which is 1-2 degrees more than the factory recommended for the premium tune. The motor seems to really like a little bit more advance and is not pinging at all.
@@totalyep yes, typically factory was ported and may be best for stock engine. Many people do use manifold for quicker advance which can raise idle.
Quadrajet Power LLC I’ve never understood that. At WOT you are actually removing advance if you go manifold. Thanks for the tips. I think I am going to leave my quadrajet alone. I am idling at 700 which is the factory spec, it’s just without the idle screw touching the blades. Otherwise the carb runs great.
Thank You very much for this video. It has really helped me.
Thank you!
Thank you for your video! Do you have some video showing the jet adjust with vaccum?
very helpful, thank you
Good info. I didn't know before seeing this. Thanks.
How/what do you set to keep the engine from stalling when coming to a stop while in "Drive" with auto trans.
check your float height. Sudden stops or acceleration should not cause engine to stall when quadrajet is set up properly.
@@QuadrajetPowerLLC Yes, that appears to be my problem. Bought a new float from you and installed it. Old float was "dead" and was much heavier than the new float. Installed new float and rebuilt carb. Still have to install carb on engine, adjust, and test-run the car. Will try to remember to let you know how it all turns out. Thanks again.
Good vidio, The air/ fuel mix screws say to bottom them out then turn each one out 3 to 3and 1/2 turns each to start. Where is a good start point for the fast idle screw
Awesome Video.... thank you very much!!
Thank you. I need to do this today, this will be a great help
Do these adjustments work the other way too?
I had to adjust my choke thermostat clocking and vacuum pull off a while ago, and ever since then, my fast idle is really high and stays there for a very long time (5 mins or so before finally dropping down a bit).
Is it possible that, by making these adjustments, I tightened up the fast idle cam?
When the choke is activated on the fast idle cam and runs at higher rpm is it possible to make it run smoother at that high idle speed? Thanks.
Just got a 86 regal with 36k miles on it. Car is prefect except for the fast idle. It's getting hung up and I'm having to flip it down some morning to get it to idle down. It's barely getting hung up. I barely touch it and it falls down. What could cause this? Any tips?
I just bought a 1970 Buick GS 455. When my choke is active the rpms are 1,000. The problem I have is, even when the engine is warm, the fast idle does not drop. When I'm in drive (TH400 Trans) tye rpms are 650 to 700 and thth's fine, but when I'm in park the rpms increase to 1,000 and when I put it in drive, I get a not so nice jerk. I have adjusted the fast and slow idle screws serveral times but can't get the fast idle to decrease. What I'm I doing wrong?
Make sure the fast idle cam moves freely, and will fall to bottom when choke isn’t engaged.
Also, make sure your choke is fully released, primary flap fully open when engine is warm. You may need to adjust choke, by bending choke rod to make sure it will fully release.
I have the same thing on my 69 Impala.
Awesome
Good information. Thank you!
Thank you.
Good video. All your videos have been helpful for me.
Question.
1986 c20 suburban.
350, non ac truck, manual transmission.
carb #17085003
The idle solenoid stays engaged keeping it at a high idle.
I can’t find any info on this issue.
What is the purpose of the solenoid ?
I thought those were for a/c equipped rigs anyways..?
What could the cause of it staying on be ?
Thanks in advance for any info.
Make sure your fast idle cam follower isn’t getting hung up on anything and that your throttle cable isn’t too tight. My car had same issue, turned out to be the cam follower (piece that swings down as choke opens) on the passenger side was getting caught on something. You will not be able to use all 4 barrels unless this cam falls out of the way. Too much tension on the throttle cable can also cause your issue.
@@frankalbano7333 Thanks. I already checked both those things. It kicks down off the cold high idle correctly. No hang ups. The cable has enough slack at idle. They are definitely not the issue.
It idles fine with the solenoid unhooked. Sits right on the idle adjustment screw.
I can physically see the solenoid move the linkage up to a high idle when you plug it in.
I’ve just unplugged it for now. It works, but I want to keep it stock and can’t find info on the purpose of the solenoid on a factory NON A/C truck.
Solenoid was used to bump up the idle some 100 rpm if the a/c was on. Could be a swapped carburetor off of a truck with factory a/c.
@@frankalbano7333
That’s what I thought too.
It puzzles me cause the truck is as original and stock as you’ll ever see. Factory no A/C. Very basic model.
Every factory vacuum line is in place. Both smog pumps. The wiring for the solenoid is factory.
As far as I can tell the only thing that had ever been changed was the rad hoses, one heater hose, filters and the fluids. I put a starter and a distributor in it.
It was ordered new for Oregon DOT.
The guy I bought it from drove it when he worked for the Oregon dot, and then bought it from them in 1999.
He sold it to me last year with 148,000 original miles.
I put 20,000 miles on it in the year I’ve owned it driving it all over the country.
Maybe it was some high idle system for idling with flashing lights and radio running..?
It did have those.
Many carbs had a solenoid for anti dieseling purposes, it should pull back when key is off to prevent idle run on.
Appreciate you
Hi, great video. Question: when my car is warmed up, the choke blade still is not totally vertical in the up position. What do I have to adjust? Its a Quadrajet in a Corvette 1978. Thanks!
You can bend the internal choke rod straighter to make it longer so it will help open the choke flap. That is best starting point.
Good info! Thanks
Great Videos
I would like to see how it is assembled, mine does not function correctly, and I'd like to know how it would be properly assembled.
My Quadrajet on my old pickup put it to the floor four-barrel kicks in but it doesn't really accelerating acts like it needs more gas. How do I do that
Make sure you have good fuel pressure and supply to carb.
Thanks for the info!!
Nice
Tanks for sharing
Hi, would anyone know if the fast idle screw below the fast idle cam shown in the video can be ordered and what the part # is. I lost mine.
I do have the curb idle screw.
How do you do this on an 87 CCC carb?
Helped me out thanks
Thank you
It is an idle stop screw, not an idle speed screw.
Idle is way ,way to fast ,so fast it is red lining quick.😮
you pointed out where the screws are but not how to adjust them
Turn screw to right, clockwise, to increase fast idle speed.
He did. Curb idle speed adjust at 3:15.