What would keep my secondaries from opening...
Drifting
Joined: Sep 1999
Posts: 1,970
Likes: 91
No. The unwinding of the choke coil as the engine heats ,pushes the choke rod up,(connects through the hole), opening the choke flap. At the same time the choke mechanism all rotates,(as my finger simulates in the video), pushing that lever to unlock the secondaries.
So, to answer your question, it's the setting of the choke that locks out the secondaries. Once the engine is warm and the choke is fully opened, the choke system has nothing to do with the secondaries
BTW a side note: when you push the gas pedal before cranking over the cold engine, everything closes in a sort of reverse order to opening. The only other thing to mention is, at this start up time, the fast idle cam rotates on the closing to set your fast idle. (adjusted with the screw seen in the video)
WHEW!! sounds like describing the mouse trap game.
Thread Starter
Le Mans Master
Joined: Jan 2007
Posts: 5,485
Likes: 7
From: Peekskill NY
Old age. The memory is shot. Anyway, you can divide the operation,(or lack of), the secondaries into mechanical or vacuum. The vacuum side has been discussed. Engine vacuum corresponding to air valve opening. Also the choke operation locking out the secondary throttle plates.
One last thing, moving to the throttle side of the carb. What physically opened the secondary throttle plates is the rod linking the primary throttle lever to the secondary lever. It is possible there's an issue there but its easy enough to check. With the car not running, block the air valve open so you can see the throttle blades.Hold the vacuum lockout open. Then open the throttle linkage. At halfway or so the secondaries should begin to open. With the throttle opened fully the secondaries should be opened to a point just shy of vertical.
One last thing, moving to the throttle side of the carb. What physically opened the secondary throttle plates is the rod linking the primary throttle lever to the secondary lever. It is possible there's an issue there but its easy enough to check. With the car not running, block the air valve open so you can see the throttle blades.Hold the vacuum lockout open. Then open the throttle linkage. At halfway or so the secondaries should begin to open. With the throttle opened fully the secondaries should be opened to a point just shy of vertical.
Glenn
Drifting
Joined: Sep 1999
Posts: 1,970
Likes: 91
Could be a few things here. I'll try to get a pic or two posted of the linkage, but try this. First make sure there's a rod connecting the primary throttle to the secondary.(that's the easy one )
If it is, look where it connects to the secondary throttle linkage. There's a vertical sort of arm that gets pushed against by that rod to open the secondary's.
You can push rearward on that arm to directly open the secondary's.(you'll have to keep that vacuum lock out opened as before). If they open, you have an issue from the primary side to secondary adjustments.
You'll notice some resistance as you push on that arm to check. That is as it should be, since there are 2 springs to open and close the secondary. If ,after you have tried this arm pushing method and you don't feel resistance or the secondary's still don't open, you need to look at all the linkage associated there.
Thread Starter
Le Mans Master
Joined: Jan 2007
Posts: 5,485
Likes: 7
From: Peekskill NY
Could be a few things here. I'll try to get a pic or two posted of the linkage, but try this. First make sure there's a rod connecting the primary throttle to the secondary.(that's the easy one )
If it is, look where it connects to the secondary throttle linkage. There's a vertical sort of arm that gets pushed against by that rod to open the secondary's.
You can push rearward on that arm to directly open the secondary's.(you'll have to keep that vacuum lock out opened as before). If they open, you have an issue from the primary side to secondary adjustments.
You'll notice some resistance as you push on that arm to check. That is as it should be, since there are 2 springs to open and close the secondary. If ,after you have tried this arm pushing method and you don't feel resistance or the secondary's still don't open, you need to look at all the linkage associated there.
If it is, look where it connects to the secondary throttle linkage. There's a vertical sort of arm that gets pushed against by that rod to open the secondary's.
You can push rearward on that arm to directly open the secondary's.(you'll have to keep that vacuum lock out opened as before). If they open, you have an issue from the primary side to secondary adjustments.
You'll notice some resistance as you push on that arm to check. That is as it should be, since there are 2 springs to open and close the secondary. If ,after you have tried this arm pushing method and you don't feel resistance or the secondary's still don't open, you need to look at all the linkage associated there.
Drifting
Joined: Sep 1999
Posts: 1,970
Likes: 91
I did as you suggested and the linkage did just as you described, but the secondaries didn't open. I have to push the arm 1/4 turn more and then they open almost verticle. It's as though the rod is not long enough to push the secondary's open. Is the adjustment in the spring-arm relationship to engage it at an earlier point?
The roe q-jet book would be a great investment. It sounds like your adjustment is way off.
There are easy ways to fix this. First being to bend that rod to simply open the secondary's sooner and further. Not the right way. There are clearance issues you should take into account.
I'll try to get the photo and adjustment procedure later.
Drifting
Joined: Sep 1999
Posts: 1,970
Likes: 91
No problem .I actually enjoy this. Here's adjustments for opening and closing secondary's from the rebuild Q-jet sheets. Shows how to set everything. Have to figure out how to make it larger. Think you can go to my pics and see it larger
Pic of the secondary lever
Pic of the secondary lever
Last edited by dennis; Mar 27, 2007 at 03:58 PM. Reason: added pic
Thread Starter
Le Mans Master
Joined: Jan 2007
Posts: 5,485
Likes: 7
From: Peekskill NY
This is awesome! I went to your pics but it wasen't there to view larger. Can you pm me the scan? I have photoshop on my machine and can blow it up larger to read the text.
Glenn
Glenn
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Drifting
Joined: Sep 1999
Posts: 1,970
Likes: 91
Thread Starter
Le Mans Master
Joined: Jan 2007
Posts: 5,485
Likes: 7
From: Peekskill NY
Thanks, Glenn