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Secondaries kick in then out right away?

  • Thread starter Thread starter Crs
  • Start date Start date Nov 20, 2010

Crs

Member
May 7, 2004
182
0
16
San Francisco, CA
Nov 20, 2010
#1
  • Nov 20, 2010
  • #1
When i mash the pedal, the secondaries kick in then out immediately after. I have a Summit 600 electric choke carb. Should i mess with the secondary spring?
Thanks, Chris
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Nov 20, 2010
#2
  • Nov 20, 2010
  • #2
Are you checking it in neutral? Vacuum secondaries will not open w/o load. There is enough in neutral for a split second in neutral but as the rpm goes up, but then they close back.
 

Az Pete

10 Year Member
Mar 30, 2005
711
18
49
Panama City, Fl.
Nov 20, 2010
#3
  • Nov 20, 2010
  • #3
Just what he said......
 

Crs

Member
May 7, 2004
182
0
16
San Francisco, CA
Nov 21, 2010
#4
  • Nov 21, 2010
  • #4
With load..... on the freeway. It is weird, secondaries go in/out, in/out, in/out.
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Nov 21, 2010
#5
  • Nov 21, 2010
  • #5
you sure its not a tranny issue?
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
10
79
Southeastern Pennsylvania
Nov 21, 2010
#6
  • Nov 21, 2010
  • #6
Hmmm… Possibly. What sort of manifold vacuum do you have? Stock or radical cam?

I'm thinking the secondaries are opening too fast, allowing the primary flow to decrease, closing the secondaries, which increases primary flow, opening the secondaries…

Perhaps a stiffer spring in the secondary motor.
 

Crs

Member
May 7, 2004
182
0
16
San Francisco, CA
Nov 21, 2010
#7
  • Nov 21, 2010
  • #7
It is a very mild 289 with an rv type cam, and a 4 barrel Summit combo upgrade. I dont think it is the trans...... it is pretty new, but stanger things have happened. I will give a stiffer spring a shot.
 

Az Pete

10 Year Member
Mar 30, 2005
711
18
49
Panama City, Fl.
Nov 22, 2010
#8
  • Nov 22, 2010
  • #8
Do this....wire the secondaries shut and drive it. With them not operating, you will see if it is the carb or the tranny. Mist of the time, one cannot really "feel" the secondaries.......
 
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