Secondaries don't open...
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Joined: Aug 2000
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From: Kingsville, ON, Canada
Secondaries don't open...
I have no idea where to look. :) The worked until the car sat for 4 months getting bodywork done on it. The choke was pretty much disabled before, and I'm suspecting the bodyshop guy noticed and thought he was being helpful. The mechanic that set it up this way, just said the carb acts like its always hot and ready to rock... any ideas on how he did that?
Eric
Eric
Safety Car
Joined: Jun 2001
Posts: 4,004
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From: Severna Park Md
Re: Secondaries don't open... (Smokester)
The mechanic may have just adjusted the choke housing all the way to the lean side. This would have a dis-abling effect of the choke but it shouldnt effect the secondaries. How have you determined that your secondaries are not working and what kind of carb do you have?
Melting Slicks
Joined: Jun 2002
Posts: 2,844
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From: Orrtanna Pa.
Re: Secondaries don't open... (Jvette73)
There's a lockout tang located on the choke side of the carb,that hits the secondary linkage when the engine is cold,preventing the secondaries from opening.My electric choke quit working so I tyewrapped the tang so as to prevent the lockout from working.(Also tyewrapped the choke wide open.)
Racer
Joined: Aug 2003
Posts: 351
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From: here oh
Re: Secondaries don't open... (The Money Pit)
:withstupid:
I think my choke went out. Light in the dash is always on for it accompianied by a buzz. Time to disconnect the wire to the choke.
I bubbized mine open with a piece of vacuum line shoved in between the choke and secondaires.
I think my choke went out. Light in the dash is always on for it accompianied by a buzz. Time to disconnect the wire to the choke.
I bubbized mine open with a piece of vacuum line shoved in between the choke and secondaires.
Thread Starter
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Joined: Aug 2000
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From: Kingsville, ON, Canada
Re: Secondaries don't open... (Riceater)
The car shifts at 2500 RPM again, and has no ***** at all. heh. When I start the car, the vacuum part that locks the secondaries closed pulls in, and stays in. Should the secondaries open if you're revving the engine while not driving as well? (I can tell just by driving it that they aren't opening up too, just wondering if they open in while in park so I will know when I find the problem.) :)
Its a Quadrajet carb, brand new last year.
Eric
Its a Quadrajet carb, brand new last year.
Eric
Burning Brakes
Joined: Nov 2000
Posts: 948
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From: Johnston Iowa
Re: Secondaries don't open... (Smokester)
I will be the first to admit I'm not a quadrajet expert but are you sure that you can get the secondaries to open by reving the car up in park?
I know that you can't get the secondaries on a vacuum operated secodary Holley carb to open with the car sitting in park and then reving it up.
Are the secondaries operated by vacuum or mechanical?
If vacuum operated could it be the diaphram?
Maybe I'm totally off since its a quadrajet.
I know that you can't get the secondaries on a vacuum operated secodary Holley carb to open with the car sitting in park and then reving it up.
Are the secondaries operated by vacuum or mechanical?
If vacuum operated could it be the diaphram?
Maybe I'm totally off since its a quadrajet.
Thread Starter
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Joined: Aug 2000
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From: Kingsville, ON, Canada
Re: Secondaries don't open... (Riceater)
I wasn't sure about the secondaries while in park, but you can easily tell the secondaries aren't working when you floor it and it shifts at 2500rpm... when they're working, it shifts around 4000-4500rpm.
To force the choke open, thats the plate that would cover the primaries right? For it to be open, the plate sits verticle in the carb? (If so, the choke is open)
Eric
To force the choke open, thats the plate that would cover the primaries right? For it to be open, the plate sits verticle in the carb? (If so, the choke is open)
Eric
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Joined: Jul 2001
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From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: Secondaries don't open... (Smokester)
I will never use any vacuum secondaries carbs again... Only problems with them... On mechanical secondaries carbs - your secondaries will always open unless the linkage is broken...(which is very unlikely)
Safety Car
Joined: Jun 2001
Posts: 4,004
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From: Severna Park Md
Re: Secondaries don't open... (Smokester)
Winging the throttle while the car is parked is not a good way to check for vacuum secondary operation. For the vac secs to work the engine needs to be under heavy load which causes the vacuum to drop. on a q-jet, the choke pull off also acts as a secondary controll. You mentioned that when you start the car that diaphram pulls and holds. Thats because there is high vacuum at idle. Now when you floor the throttle while driving the engine is under heavy load and the vacuum drops. Thats when the vacuum diaphram releases and allows the secondaries to open. When you wing the throttle in neutral there is not much of a load so the vacuum doesnt drop far enough to check for secondary operation. Flooring the gas in neutral is a good way to blow the engine. I wouldnt do it. A safer way to check for secondary operation is to dis-able them and test drive to see if there is a difference. If you notice a difference then they were working before. Wire them shut and test drive again. The early transmission upshift(2500rpm) could be a trans related problem. What year car are you working on and what trans does it have?
Pro
Joined: Sep 2002
Posts: 541
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From: Epping NH
Re: Secondaries don't open... (Smokester)
Haven't seen this mentioned.
After major engine work, my car just did not seem to accelerate properly. I had a sense that my accelerator cable seemed to be binding. I took my air cleaner off and had my daughter step on the gas. I watched the throttle linkage go from 10 o'clock (idle) to 12 o'clock position. I then grabbed the cable and pulled the linkage to 2 o'clock by hand. Ah, hah! The accelerator cable seems to have either slipped or stretched to the point where even when putting the pedal to the metal, I was not getting full acceloration. I adjusted the cable (pulled it back until I could see the linkage start to move, then tightened the clamp) and it now runs like a champ. Of course, your mileage may vary. Good luck.
Mark
After major engine work, my car just did not seem to accelerate properly. I had a sense that my accelerator cable seemed to be binding. I took my air cleaner off and had my daughter step on the gas. I watched the throttle linkage go from 10 o'clock (idle) to 12 o'clock position. I then grabbed the cable and pulled the linkage to 2 o'clock by hand. Ah, hah! The accelerator cable seems to have either slipped or stretched to the point where even when putting the pedal to the metal, I was not getting full acceloration. I adjusted the cable (pulled it back until I could see the linkage start to move, then tightened the clamp) and it now runs like a champ. Of course, your mileage may vary. Good luck.
Mark
Le Mans Master
Joined: Oct 2002
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From: Las Vegas - Just stop perpetuating myths please.
Re: Secondaries don't open... (Smokester)
:( Sorry. I wanted to say something here but every time I start thinking about Q-jets I get some sort of diarrea. :U
Burning Brakes
Joined: Feb 2000
Posts: 770
Likes: 283
From: Middleton, Id
Re: Secondaries don't open... (cardo0)
Q jets have mechanical secondaries. The only vacuum operated part is the air valve which is very hard to get to open by reving the car in neutral. Secondaries will not open when choke is closed.
Thread Starter
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Joined: Aug 2000
Posts: 56
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From: Kingsville, ON, Canada
Re: Secondaries don't open... (Burgundy 69)
Burgandy 69: Thanks man. It wasn't quite that... the body shop guys noticed there were 2 floormats on the passenger side of the car, and decided to be helpful and move it back.... they're just generic aftermarket ones that are really too big. I'd forgotten about that, and didn't notice it. Removed the mat, and voila, all is well again. Something simple. :) It was your post that made me think of it.
At least I didn't spend money taking it to the mechanic for that. hehe
At least I didn't spend money taking it to the mechanic for that. hehe
