i reached down with my finger and tried to pull up on the secondary lever but it didnt move. i tried it at idle and with the throttle opened. you would think it would be really free if just vacuum lifts it. anyone ????????
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i reached down with my finger and tried to pull up on the secondary lever but it didnt move. i tried it at idle and with the throttle opened. you would think it would be really free if just vacuum lifts it. anyone ????????
Ah, that's because the linkages prevent the secondary from opening until the primary butterfly is nearing full open. It's a safeguard to prevent the secondary from cracking open too early and drowning the inlet manifold in fuel. You can shave a little off the primary linkage 'cam' to allow the secondary to open earlier, giving the engine more mid range torque though!
Should've added that you can open the secondary with the engine off by simply twisting the throttle linkage full open, then grabbing the end of the secondary shaft and turning it manually...
Hello,
I'm brand new to my 87, and my secondary setup was pretty bad. The diaphragm had a couple tears in it where the pleats would tend to form on contraction. Cheap bastard over here, so I Dremeled the actuato lip apart and used some small scraps of innertube and some coats of rubber cement to patch, and appears to be holding for now.
My linkage was assembled incorrectly also. The little arm was positioned to the right of the small vacuum pull arm thing mounted above, so the secondary could just flop an eight of a turn or so from closed. I had to remove the throttle plate, pull out the shaft, correctly assemble/position the linkage, and re-assemble. There's a small plastic or rubber roller on the secondary shaft that contacts a plate on the primary shaft (the cam that geezer101 mentions) which rotates out of the way and eventually allows the secondary to rotate open with adequate throttle input. I took a couple pictures, may try to post here later.
Good luck over there, I'm struggling a bit with mine also.
If anyone digs up this thread and cares, I posted pics up of my carb.
https://www.flickr.com/photos/354657...7663531928835/
That one shows the secondary arm hung up, not allowing it to open
The second one shows the arm after adjustment, where the round roller rides against the cam on the primary. Secondary actuator is removed in this pic. When the throttle cable pulls and rotates the primary clockwise that protrusion falls away, allowing the secondary actuator to pull on the arm and open the secondary throttle.
https://www.flickr.com/photos/354657...7663531928835/
Bunch of pics on there if anyone needs to ID something. Hope that helps a bit.
Glad to here you figured it out. Now you are heading to become an expert in carbs. I there not to hard. They just take time to figure out.