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Unread 02-13-2013, 11:29 AM   #31
Beachcruiser
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1987 YJ Wrangler 
 
Join Date: Feb 2008
Location: Raleigh, NC
Posts: 372
You can also adjust the accelerator pump by varying the hole on the throttle arm in which the rod sits...and bending the rod, itself.

There should be no 'play' at the pump arm. It shouldn't be 'almost touching'...the pump arm should be under spring load (from the internal spring) and have the diaphram just slightly into its range of motion. This ensures a rapid pump shot as soon as you press the pedal.

That pump shot is the first thing you feel on throttle tip in, the power valve fillls in (on aggressive pedal action) after the acc. pump is done.

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Unread 02-13-2013, 01:22 PM   #32
Jax89Jeeper
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1989 YJ Wrangler 
 
Join Date: Mar 2011
Location: Jacksonville, Florida
Posts: 345
Quote:
Originally Posted by Beachcruiser
You can also adjust the accelerator pump by varying the hole on the throttle arm in which the rod sits...and bending the rod, itself.

There should be no 'play' at the pump arm. It shouldn't be 'almost touching'...the pump arm should be under spring load (from the internal spring) and have the diaphram just slightly into its range of motion. This ensures a rapid pump shot as soon as you press the pedal.

That pump shot is the first thing you feel on throttle tip in, the power valve fillls in (on aggressive pedal action) after the acc. pump is done.
Yes, changing the power valve should be done once the accel pump is eliminated from the equation.
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Unread 09-24-2013, 09:28 AM   #33
drespecki
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1983 CJ7 
 
Join Date: Jan 2007
Location: Arizona
Posts: 1,169
Quote:
Originally Posted by CJ51973 View Post
I am 18 in hg at idle with a 7.5 power valve. I have always thought my stumble to be lean. I feather the pedal a little and it takes off. It is much better then it was if you read through this thread. It doesn't exist in low range. I have the 6.5 power valve so maybe I will just stick it in there and see. Perhaps I am a little rich. If it gets worse then I will hunt up a 8.5 and try that.

Did you ever resolve the power valve problem/situation? I am in a similar situation and am looking for comparative fixes so I don't have to pull my carb off so many times..
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Unread 09-24-2013, 03:06 PM   #34
CJ51973
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1988 YJ Wrangler 
 
Join Date: Aug 2004
Location: Versailles, KY
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It did help. Almost perfect. So close I am not messing with it. I plan to remove the POs leaking header and put a cast exhaust manifold back on this winter maybe so I will what the new intake gasket does just in case it's leaking and I couldn't find it
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Unread 09-25-2013, 12:46 PM   #35
drespecki
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Originally Posted by CJ51973 View Post
It did help. Almost perfect. So close I am not messing with it. I plan to remove the POs leaking header and put a cast exhaust manifold back on this winter maybe so I will what the new intake gasket does just in case it's leaking and I couldn't find it


Did you go with the 6.5 pv and the 47 jets? Are you at sea level or?
Thanks..
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Unread 09-25-2013, 05:09 PM   #36
CJ51973
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1988 YJ Wrangler 
 
Join Date: Aug 2004
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Not sure what jets (it's been three years). But yes on the 6.5
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