1982 (2.5 Iron Duke) cj5 open or closed loop carb - JeepForum.com
LinkBack Thread Tools
post #1 of 3 Old 09-25-2011, 10:07 AM Thread Starter
Registered User
1982 CJ5 
Join Date: May 2011
Location: Houston
Posts: 6
1982 (2.5 Iron Duke) cj5 open or closed loop carb

I just bought a non returnable carb for my 82 CJ5 it is an electronic feed back carb or closed loop carb....
(it seems some 80 - 83 cj5's were elect. FB and some weren't)
Now it look like I need an non electronic or open loop carb I have looked into this as far as I can and it seems "The carburetor operates in open loop until the oxygen sensor reaches a certain temperature (approximately 600F). The carburetor also goes into open loop when a richer-than-normal air/fuel mixture is required, such as during warm-up and heavy throttle application"
so is it possible to convert the carb to a open loop or or is there any need to if the carb is not hooked to any electronic feedback sensors should it stay in open loop mode
Or am I just totally off base here

jclaude53 is offline  
Sponsored Links
post #2 of 3 Old 09-25-2011, 12:24 PM
Registered User
2004 TJ Wrangler 
Join Date: Sep 2007
Location: Dallas (Wylie)
Posts: 267
I have dealt with several oxygen sensor equipped systems in the past and all of them, none were Jeeps, operated in a similar manner: The system ran at an "open loop" setting unless it was receiving a signal from the O2 sensor.

For Example: Volswagens are set up to run VERY rich if there is no O2 signal, but they will run. The excuse for this richness is that it will not burn up an engine, like a lean setting will.

A honda that I had would work quite well with no O2 sensor - the engineers set the default open loop pretty close to what was seen in normal operating conditions at sea level.

I would hypothesize that if you set the carburetor to the proper mixture without the O2 sensor hooked up then you would have no issues. The O2 sensor usually serves to lean the mixture for improved emissions and fuel economy. If you get it set right you will just be operating like a normal carb without the leaning benefits of the feedback carb.

Or perhaps I'm talking out of my *** when it comes to Jeeps...
PlaneJob is offline  
post #3 of 3 Old 09-25-2011, 10:24 PM Thread Starter
Registered User
1982 CJ5 
Join Date: May 2011
Location: Houston
Posts: 6
Thanks for your reply that is what I was thinking but needed some confirmation that I'm not totally off base with this theory I could use all the feedback I can get about this again thanks
jclaude53 is offline  

Quick Reply

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:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.

Email Address:


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.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Jeep Forums Replies Last Post
Iron Duke carb and fuel line? SlikRic Jeep CJ Forum 10 05-24-2012 05:41 AM
Carb help 151 iron duke wildbillnv Jeep CJ Forum 4 12-13-2010 10:04 PM
where can i buy a replacement carb for iron duke NinjaTurlteSean Jeep CJ Forum 4 12-23-2009 07:56 PM
Thermostat/ open,closed loop question scooter Jeep CJ Forum 5 11-29-2009 03:45 PM
Carb options on the 4 cyl Iron Duke... Jayson44 Jeep CJ Forum 3 02-29-2008 09:32 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome