quadrajet question
Thread Starter
Instructor
Joined: Mar 2007
Posts: 110
Likes: 1
quadrajet question
Hi guys, i have a mint 79 L-48 that does not seem to open the secondaries all the time.Choke is opening all the way when hot,
lock-out lever is in the open position,but it seem to take several seconds or forever when passing.Is this common with the 195 hp
350.full pedal off the line and it will catch 2nd still without any
secondary roar and then finally you hear the secondaries open.
secondary spring is set where if you just touch the air valve with
the engine off it will fall open.Any comments? Thanks
lock-out lever is in the open position,but it seem to take several seconds or forever when passing.Is this common with the 195 hp
350.full pedal off the line and it will catch 2nd still without any
secondary roar and then finally you hear the secondaries open.
secondary spring is set where if you just touch the air valve with
the engine off it will fall open.Any comments? Thanks
Tech Contributor
Joined: Aug 1999
Posts: 14,379
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
First, if the airvalve falls open upon the lightest touch, it's too loose. You need to have 3/4 turn windup up the airvalve spring.
Next, check to see if you are getting full secondary throttle opening. Most C3s never get wide open throttle. Have someone press the gas pedal to the floor and observe the secondary throttle shaft and linkage on the driver's side of the carb. With the pedal to the floor, verify that you cannot open the secondary throttle further with your finger. If you can, you either need to remove your floor mat or bend your gas pedal arm.
Finally, check your choke pulloff. Suck it retracted using a long hose and then release the suction. It should fully extend within 2 seconds.
If all items check out okay, your secondaries are working right.
Next, check to see if you are getting full secondary throttle opening. Most C3s never get wide open throttle. Have someone press the gas pedal to the floor and observe the secondary throttle shaft and linkage on the driver's side of the carb. With the pedal to the floor, verify that you cannot open the secondary throttle further with your finger. If you can, you either need to remove your floor mat or bend your gas pedal arm.
Finally, check your choke pulloff. Suck it retracted using a long hose and then release the suction. It should fully extend within 2 seconds.
If all items check out okay, your secondaries are working right.
Racer
Joined: Feb 2001
Posts: 405
Likes: 15
From: Minneapolis
Let's face it, the stock '79 L-48 has about as much kick as a Honda Civic. (or less) 
If your air valve is set properly and you've checked the items previously mentioned, then I'd also take a look at the other components of the system. Remove your distributor cap, and rotor and check to be sure your advance counter weights aren't stuck. (it happened to me) Lube them with some WD-40 to be sure they are completely free.
Then make sure your timing is set properly.
If your air valve is set properly and you've checked the items previously mentioned, then I'd also take a look at the other components of the system. Remove your distributor cap, and rotor and check to be sure your advance counter weights aren't stuck. (it happened to me) Lube them with some WD-40 to be sure they are completely free.
Then make sure your timing is set properly.
