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Secondaries on quad

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Old Oct 25, 2018 | 10:05 PM
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Default Secondaries on quad

Of course, another redundant commonly asked question.... When I am in 1/2 gear on the street when the car is cold, it fluctuates between running good and 'bogging' down. I use the term lightly because it just seems like it speeds up, slows down, speeds up etc...;; When it's warm no problems. Now, when in 4th gear on the highway and I'm causing around at 60-70 mph, and I punch it, there's a slight hesitation (bog) before it takes off like a rocket ship. But it does indeed take off. Is this a secondary air valve adjustment? I know that I must unscrew the allen screw first, and then adjust the adjustment screw. With my symptoms, which way would I go 1/8 of a turn? Is there supposed to be a hesitation son ra millisecond and then jerk when doing 60-70 on the highway and flooring it?
THANKS!

Last edited by BarretHC1; Oct 25, 2018 at 10:15 PM.
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Old Oct 26, 2018 | 08:59 AM
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Originally Posted by BarretHC1
Of course, another redundant commonly asked question.... When I am in 1/2 gear on the street when the car is cold, it fluctuates between running good and 'bogging' down. I use the term lightly because it just seems like it speeds up, slows down, speeds up etc...;; When it's warm no problems. Now, when in 4th gear on the highway and I'm causing around at 60-70 mph, and I punch it, there's a slight hesitation (bog) before it takes off like a rocket ship. But it does indeed take off. Is this a secondary air valve adjustment? I know that I must unscrew the allen screw first, and then adjust the adjustment screw. With my symptoms, which way would I go 1/8 of a turn? Is there supposed to be a hesitation son ra millisecond and then jerk when doing 60-70 on the highway and flooring it?
THANKS!
Ok couple things, it most likely isn't a secondary adjustment issue when it is cold and bogging (unless you are going Wide open throttle on a cold engine ?!?!). The secondaries on the Qjet open mechanically, but the secondary air door opens in response to vacuum. So the first thing to do is check your throttle linkage. Make sure when you push the pedal, your secondary butterfly valves open to a vetical position at WOT (you'll have to manually open the air door to look down).

How do your plugs look? The bogging is most likely a rich condition, especially when the engine is cold. Check your choke adjustment, it may not be fully opening.

As for the 4th gear pulls on the highway, it is possible that is a secondary issue. Don't just loosen the allen head, you have to have a flat head screw driver holding the adjustment screw when you loosen it so you don't lose your position/spring tension. Make small adjustments (half a turn or so).
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Old Oct 26, 2018 | 09:31 AM
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No, not WOT on cold engine. Just cruising gently. Almost feels as if I push the gas let do push the gas let off..... a jerkiness feeling lol.
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Old Oct 26, 2018 | 10:43 AM
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Your cold-run symptoms sound like improper choke pulloff adjustment, which will cause either a lean or rich condition when cold with resultant erratic behavior.

There should not be a bog going into the secondaries. Assuming your choke pulloff is operating correctly and that the secondary airvalve rod is attached, set the secondary spring windup to 3/4 turn. This also assumes your accelerator pump is providing a good fuel shot - check it.

Lars

Last edited by lars; Oct 26, 2018 at 10:43 AM.
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Old Oct 26, 2018 | 03:01 PM
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Hi Lars,
I have the same symptoms, erratic behavior or slight bog when cold but secondaries open up just fine when warm.
So how do I test the choke pull off?
Thanks, Pete.
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