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Unread 07-19-2012, 08:30 AM   #16
Old4X
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Quote:
Originally Posted by befumo View Post
But why would this affect idle speed? Seems to be something funky going on. It refuses to fast idle properly as well.. even though it is set to 1700. (Changed it with the EGR valve hose plugged, second cam etc). It will start up to 1700 then start increasing towards 2,000 rpms.

Went through and checked all vacuum hoses today, all good.


re: Manifold heater: Didn't mean to check the operation, but check the mounting for vacuum leaks. These are known to cause intermittent vac leaks, and are rarely checked as they aren't visible without a mirror.

If your carb won't hold a steady idle when warmed and properly adjusted, check the return springs (2), and check the throttle shaft bushings for wear. Worn shaft bushings will cause the throttle to stick partially open at idle when warm.

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Unread 07-19-2012, 11:04 AM   #17
Wrenchtosser
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1990 YJ Wrangler 
 
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Location: Roseburg, Oregon
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Quote:
Originally Posted by befumo
Not sure what exactly you mean lol. The high idle screw sits on the fast idle cam which sets when you pump the gas before you start it. Then the screws rides up the fast idle cam with the choke, or that is how its supposed to work.

For setting the fast idle go below, its the second cam step up from the bottom by the way. Made that mistake..

http://home.sprynet.com/~dale02/solvac.htm#setting
Great info! Thanks for the picture and the link! Now I have a MUCH better understanding of how that Sol Vac thingie works. Much appreciated!
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Unread 07-19-2012, 12:46 PM   #18
OregonNBeyond
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1990 YJ Wrangler 
 
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Thanks Bef, Should have the clutch job done by tomorrow, ugh, so that will be next on the list. Easy by comparison
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Unread 07-19-2012, 04:54 PM   #19
befumo
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Quote:
Originally Posted by Old4X View Post
re: Manifold heater: Didn't mean to check the operation, but check the mounting for vacuum leaks. These are known to cause intermittent vac leaks, and are rarely checked as they aren't visible without a mirror.

If your carb won't hold a steady idle when warmed and properly adjusted, check the return springs (2), and check the throttle shaft bushings for wear. Worn shaft bushings will cause the throttle to stick partially open at idle when warm.
Return springs i am assuming you mean..



This is how the screw sits on the fast idle cam after the normal two pumps of the accelerator before starting.



Starting to run out of ideas here, just manually tested the vacuum choke pull off and it works.
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Unread 07-19-2012, 04:58 PM   #20
superj
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i had the return spring problem a lot on my weber 34. the springs just wouldn't pull the accelerator arm back enough every time i let off the gas. sometimes that would and sometimes it would stick open at 1000 rpm. it sucked. i had to put some heavy springs on and hten it was so heavy it made it hard to drive the jeep smoothly. i think it was just because my weber 34 was a crappy knock off of a weber or something. it was new when i got this jeep and it still sucked. i never had an issue like that on any other weber i have ever owned or on any of the motorcraft or holleys i have owned
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Unread 07-19-2012, 05:02 PM   #21
befumo
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Well i noticed that some people have two springs. Does anyone else run two springs, is this stock or? I guess i will go ahead and try it.
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Unread 04-24-2013, 12:52 PM   #22
wturner1981
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newbe what does nuttered mean .and how are you getting 22mpg im get 13 mpg on 31x10.50
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