Weber Set-Up and Tune Discussion - Page 33 - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep CJ Forum > Weber Set-Up and Tune Discussion

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineGrizzly Lockers available at Rockridge4wd.comThe ULTIMATE "Selectable" Locker System! Brough

Reply
Unread 08-06-2012, 03:18 PM   #481
svenster
Registered User
1985 CJ7 
 
Join Date: Jul 2008
Location: san rafael, california
Posts: 83
found lean best idle at 1 1/2 on the mixture screw. 1 turn in on the speed screw only gives me 520 rpm with 3 inches of vacuum. what am i doing wrong? the speed screw is in too far is what i am feeling but i don't know how to increase my rpm without adjusting the speed screw. any adjustment on my timing makes it want to shut off.

svenster is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 03:20 PM   #482
Joe73CJ5
Registered User
1973 CJ5 
 
Join Date: Jun 2012
Posts: 179
Check timing.
Joe73CJ5 is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 03:23 PM   #483
svenster
Registered User
1985 CJ7 
 
Join Date: Jul 2008
Location: san rafael, california
Posts: 83
it floats from 8-10. what about it? too...? not enough....?
svenster is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 03:27 PM   #484
uptillnow
Senior Member
 
uptillnow's Avatar
 
Join Date: Mar 2009
Location: Placentia, California
Posts: 504
Quote:
Originally Posted by svenster View Post
things are looking up. finally idles and no dieseling when shut off. idles right around 620-ish rpm +/- 200 rpm fluctuation. timing at 12*, but fluctuating b/w 14-11*. mixture screws at 1 turn out. speed screw in about 1/8 turn. found a vacuum leak under the linkage plate i bolted into the intake. fixing that ASAP. still no s port hooked to dizz and not sure how to tackle the 0 vacuum at s port at idle issue. would love some more help. thanks to everyone for helping me get to where i am now. haven't driven it yet but keeping fingers crossed that i will be pleasantly surprised.
Svenster.
This was your post #460.
It looks like things have changed.
UPTILLNOW
uptillnow is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 03:31 PM   #485
svenster
Registered User
1985 CJ7 
 
Join Date: Jul 2008
Location: san rafael, california
Posts: 83
seems so. i removed a bracket that was bolted into my manifold to eliminate a vacuum leak. i then drove it around and realized it had a huge amount of pre-det. retarded the timing to eliminate the ping and here i am now.
svenster is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 03:38 PM   #486
svenster
Registered User
1985 CJ7 
 
Join Date: Jul 2008
Location: san rafael, california
Posts: 83
things are getting better if i ignore the blatant that slaps my face and focus on the big picture. i have a better jetted carb, i'm sure, and have also acquired a new timing light and vacuum gauge. can't gripe about that. have any suggestions for me? could it be my minimal vacuum line hook-up?
svenster is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 03:53 PM   #487
Matt1981CJ7
Web Wheeler
 
Matt1981CJ7's Avatar
1981 CJ7 
 
Join Date: May 2011
Location: Elbert, CO
Posts: 10,468
The timing at idle should not "float", especially not 2 degrees. Is the manifold vac steady at idle? If so, what does it record?

Everything is pointing to a warn out timing chain, or distributor gear, perhaps a failing module.

Your pics show a vac layout that I'm not familiar with. The PCV doesn't appear correct. Did you ever remove the FPR, and re-plumb your fuel delivery correctly?

Matt
Matt1981CJ7 is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 03:59 PM   #488
svenster
Registered User
1985 CJ7 
 
Join Date: Jul 2008
Location: san rafael, california
Posts: 83
i have not checked manifold vacuum yet, only ported. i have not removed the FPR but i did re-route so the filter is closer to the carb, away from the exhaust manifold, and oriented in the 12' position. will it help if give you a reading of manifold vacuum at idle?
svenster is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 04:13 PM   #489
svenster
Registered User
1985 CJ7 
 
Join Date: Jul 2008
Location: san rafael, california
Posts: 83
all my components are fairly new btw, as i just did a rebuild not too long ago.
svenster is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 04:31 PM   #490
svenster
Registered User
1985 CJ7 
 
Join Date: Jul 2008
Location: san rafael, california
Posts: 83
just say the word and i will check it or try it at this point
svenster is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 04:55 PM   #491
Matt1981CJ7
Web Wheeler
 
Matt1981CJ7's Avatar
1981 CJ7 
 
Join Date: May 2011
Location: Elbert, CO
Posts: 10,468
Svenster,

This is what a manifold vac reading will tell you:

"When using the gauge, hook into a good port directly off of the intake manifold. Any competent engine should be running between 18-22 inches of mercury.

(1) The vacuum gauge can be used to check for a leak in the valve train, intake manifold or head gasket. With the engine at normal idle and at operating temperature, hook up the gauge. Normal operation would have the needle/ pointer holding steady and not fluctuating. If the needle holds steady, than drops an inch or more, and then returns again to normal, and repeats… this signals one or more engine valves are closing but not seating properly, thus creating a leak. Each time the valve doesn't seat properly, the pointer fluctuates. The fluctuation isn't much, maybe 1-3 inches of mercury.

(2) If the pointer drops sharply 5-10 inches from normal, and then returns… this signals a cylinder head gasket. This behavior will repeat itself. If the leak is between two adjacent cylinders, the leak will be more pronounced.

(3) If the pointer/ needle fluctuates constantly at a reading of 3-8 inches of mercury BELOW normal, It indicates intake system leakage.

(4) If you think you may have a "back pressure" issue, get the vehicle at normal operating temperature and slowly bring engine to 2,000 rpms. Close throttle quickly. If no back pressure is present, the pointer will jump past your normal reading and smoothly return to normal, just as fast. If it is slow or uneven return, there is an issue of back pressure. You can also test it another way… hold the engine at 2,000 rpms and watch needle. If it begins to decrease gradually instead of holding steady, there is an exhaust restriction somewhere.

(5) Continuous pointer movement an inch of so above or below normal indicates the need for further checking of the ignition system with electrical test equipment. You may have a weak ignition coil, high tension cable leaks, bad distributor cap, bad spark plug or incorrect spark plug gapping.

From "Petersen's Basic Tune up and Test Equipment."


Matt
Matt1981CJ7 is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 05:36 PM   #492
svenster
Registered User
1985 CJ7 
 
Join Date: Jul 2008
Location: san rafael, california
Posts: 83
manifold vacuum readings... when i increase rpm with speed screw to 820, vacuum reads 16.5, and fluctuates to 16.75 and back. idle rpm jumps between 790-840, but most constant around 820. for some reason in the beginning of the test my timing gun would read 710 in a flash, and then read back to 820ish. when my electric fan kicks on the idle and vacuum drop. does that tell us that i need to test some electrical components?
svenster is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 06:46 PM   #493
swatson454
Mall-crawlin' Hot Rodder
 
swatson454's Avatar
1983 CJ7 
 
Join Date: May 2009
Location: Dripping Springs, TX (soon)
Posts: 4,909
You've got a sneaky gremlin somewhere, buddy. Hopefully not a problem with the rebuild.

I'll try to give it some more thought...


Shawn
__________________
Live in a way that those who know you but don't know God will come to know God because they know you.
swatson454 is offline   Reply With Quote Quick reply to this message
Unread 08-06-2012, 06:52 PM   #494
svenster
Registered User
1985 CJ7 
 
Join Date: Jul 2008
Location: san rafael, california
Posts: 83
thank you. compression test in the thoughts?
svenster is offline   Reply With Quote Quick reply to this message
Unread 08-08-2012, 11:38 AM   #495
svenster
Registered User
1985 CJ7 
 
Join Date: Jul 2008
Location: san rafael, california
Posts: 83
Twitching to make progress...
svenster is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.