weber carb idle issue -
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post #1 of 3 Old 01-08-2012, 08:36 PM Thread Starter
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1987 YJ Wrangler 
Join Date: Aug 2010
Location: montreal
Posts: 17
weber carb idle issue

Hello everyone, i installed the weber carb and can't seem to figure out why my idle speeds up when the engine is warm and slower when it is cold.
When the engine is cold it idles at around 500 RPM and when warm at around 900-1000 RPM.
Can anyone please help?
Thank you in advance

4.2l I6

goreboy8 is offline  
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post #2 of 3 Old 01-08-2012, 09:45 PM
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1983 CJ8 
Join Date: May 2008
Location: N.E. Alabama
Posts: 2,649
You have two idle speed screws, a fast idle that should be in play while the choke plates are closed and or during some time while they are opening. The other is the Curb idle speed screw, both control the throttle plate position.

If your fast idle speed screw is set too shallow to reach the fast idle cam or so deep that it cannot 'climb' onto it, either will prevent the function that was intended, faster idle during the warmup.

Likewise the Curb Idle speed screw set too deep could allow the same issue... choke plate in play= slow idle, choke plate open=faster idle speed, if the fast idle screw is out of position.

The cure is to set the screws.

Which "Weber" have you mounted?
mcmud is offline  
post #3 of 3 Old 01-09-2012, 07:55 AM Thread Starter
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1987 YJ Wrangler 
Join Date: Aug 2010
Location: montreal
Posts: 17
i have the WK551-34
goreboy8 is offline  

carb , idle , issue , slow , weber

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