Author Topic: secondary not opening  (Read 2579 times)

Offline firedan

  • Newbie
  • *
  • Posts: 4
secondary not opening
« on: November 28, 2012, 02:16:09 PM »
carb is 17058266 on 78 TA W-72 at WOT the mechanical part is not letting the secondary snap open. If i push the linkage behind the choke bowl it will mone the lock out enough and they snap open as should. All this is happening with choke wide open. is the adjustmentthat i am missing...

Offline Shark Racer

  • Jet Head
  • ****
  • Posts: 288
Re: secondary not opening
« Reply #1 on: November 28, 2012, 05:10:28 PM »
If the engine is running the choke pull-off will prevent this from happening at idle. When vacuum drops(heavier accel) the choke pull-off releases and allows the secondary air-valves to open.

This is expected.

The second half of this is the secondary lock-out lever, when the choke is engaged that should have pressure on it to prevent the secondary throttle blades from opening.

Offline firedan

  • Newbie
  • *
  • Posts: 4
Re: secondary not opening
« Reply #2 on: November 28, 2012, 05:54:12 PM »
the vacuum part works normal but the lock out wont let the lower secondary open

Offline 73 Z28

  • Carb lover
  • ***
  • Posts: 73
Re: secondary not opening
« Reply #3 on: November 29, 2012, 09:20:14 AM »
If the lower lockout is preventing the secondaries from opening ,  2 things will cause this. First if the choke element (spring) is malfunctioning it will not heat up and rotate the lockout away from the secondaries.  The other thing that will
cause this is if the pin on the back of the choke housing has worn or gotten loose where it attaches to the lever arm.
Is your choke electric or hot air on this carb?  If it is hot air, check the tube going to the choke housing to make sure it is not rusted out or blocked. If it is electric, make sure that there is no gasket between the choke and the housing and
that with 12volts to it, it heats up and moves the element (spring looking piece). Now if the pin is loose on the lever or just worn down some, you can cut a small piece of vacuum hose and slip it over the pin , just verify that when rotating the choke in the housing (to adjust it) that it will disengage the lockout lever when it is moved to simulate the choke in the full open position.
Paul

Offline firedan

  • Newbie
  • *
  • Posts: 4
Re: secondary not opening
« Reply #4 on: November 29, 2012, 03:19:11 PM »
it is hot air i tore apart and it was binding up and there is a screw adjustment under the choke bowl that i messed with and got lucky as they snap open great now and all seems to work, thanks all for your help...