Dead spot in accelerator from idle to 1st gear... - JeepForum.com

 
LinkBack Thread Tools
post #1 of 15 Old 11-15-2012, 01:22 PM Thread Starter
matthewleeblair
Registered User
1983 CJ7 
 
Join Date: Oct 2012
Location: Anniston
Posts: 282
Dead spot in accelerator from idle to 1st gear...

1983 CJ7

Carter BBD

256 L6 4.2L

I've recently replaced the fuel filter (though I just read a post where someone said to start the engine before reattaching the new fuel filter to get anything out that may have been in the line). Removed the carburetor venturi assembly, cleaned it out, replaced the worn gaskets on the venturi assembly. I also put some seafoam in the gas tank with some fresh gas and ran it through the engine for about 5 minutes.

It still seems sluggish to dead-spot coming from idle to 1st gear.

Should I take the whole carb off, clean it all out, rebuild, and replace? I'm a little nervous about this. I think I did ok getting the venturi assembly out and cleaned but not so sure about taking the whole thing off.

What do you guys think it is?

Matt B

matthewleeblair is offline  
Sponsored Links
Advertisement
 
post #2 of 15 Old 11-15-2012, 01:56 PM
cjjon7
Registered User
1983 CJ7 
 
Join Date: Dec 2009
Location: Rocklin
Posts: 1,555
Garage
I would put money on it being the carb itself with a multitude of old age problems. I dont think the bbd has an accelerator pump, right?

When I had one on my I6, it gave me problems for years until I finally broke down and replaced it with a Holley, looking back Id have gone tbi with 4.0 head... but nonetheless it solved 99 % of my troubles.
cjjon7 is offline  
post #3 of 15 Old 11-15-2012, 02:09 PM Thread Starter
matthewleeblair
Registered User
1983 CJ7 
 
Join Date: Oct 2012
Location: Anniston
Posts: 282
Funds are low, so a new carb is not possible right now.
matthewleeblair is offline  
post #4 of 15 Old 11-15-2012, 02:13 PM
RustyNutts
Registered User
1994 YJ Wrangler 
 
Join Date: Mar 2012
Posts: 98
I thought the same thing about the carb and dreaded taking it apart for a rebuild. --different carb from yours, Carter YF single barrel
In retrospect, it wasn't nearly as challenging as it seemed beforehand.
Get yourself a rebuild kit, chemical dip for carburetor parts, compressed air, some old toothbrushes, and a digital camera.
Take pics of it before from all angles showing all hookups, hoses, lines, etc.
As you take stuff apart, large or small, take a pic.
It could be the next day (if you soak your parts overnight) before you reassemble, so the pics are key.

It's not hard, but it is tedious and the pics keep you on track. The rebuild kit comes with exploded views of everything and how it goes.
Good Luck.

That being said, have you tried just driving the tee-total sheet out of it for a few minutes? The ol' Italian tune-up!!
RustyNutts is offline  
post #5 of 15 Old 11-15-2012, 02:17 PM
cjjon7
Registered User
1983 CJ7 
 
Join Date: Dec 2009
Location: Rocklin
Posts: 1,555
Garage
Quote:
Originally Posted by RustyNutts View Post

That being said, have you tried just driving the tee-total sheet out of it for a few minutes? The ol' Italian tune-up!!


Never heard that one before thats awesome. I used to do those with the I6 all the time to try and blast something outta that carb. haha
cjjon7 is offline  
post #6 of 15 Old 11-15-2012, 02:32 PM Thread Starter
matthewleeblair
Registered User
1983 CJ7 
 
Join Date: Oct 2012
Location: Anniston
Posts: 282
hahahaha!!! That's a good one. Maybe I can scare the neighbors while I'm at it haha.

Thanks for the encouragement about rebuilding it. I know that's what I should probably do anyway.

Keep learning as I go. One question about the chem dip... after using it for the carb, is it ok to store it and reuse it on something else?
matthewleeblair is offline  
post #7 of 15 Old 11-15-2012, 07:17 PM Thread Starter
matthewleeblair
Registered User
1983 CJ7 
 
Join Date: Oct 2012
Location: Anniston
Posts: 282
Anyone have any other thoughts on what could be causing this problem?
matthewleeblair is offline  
post #8 of 15 Old 11-15-2012, 07:28 PM
davbytrace
Registered User
1979 CJ7 
 
Join Date: May 2011
Location: clinton
Posts: 487
Maybe the accelerator cable is bending and taking up slack (dead spot) rather than moving the throttle linkage at some point in its travel. This will have the appearance of a dead spot.
davbytrace is offline  
post #9 of 15 Old 11-15-2012, 07:37 PM Thread Starter
matthewleeblair
Registered User
1983 CJ7 
 
Join Date: Oct 2012
Location: Anniston
Posts: 282
I'll check that out too. Thanks!
matthewleeblair is offline  
post #10 of 15 Old 11-16-2012, 03:48 AM
86cj74.2L
Web Wheeler
 
86cj74.2L's Avatar
2004 WJ 
 
Join Date: Jul 2006
Location: Stouchsburg, PA
Posts: 10,029
Grab the the bellcrank where the throttle cable attaches to. See how much up and down play it has.

When the bushings get loose the needles and accelerator pump do not track the throttle plate. The butterfly's opening before the accelerator pump arm moves causes a lean hesitation.

Have you ever adjusted your idle mixture screws?
86cj74.2L is offline  
post #11 of 15 Old 11-16-2012, 08:39 AM Thread Starter
matthewleeblair
Registered User
1983 CJ7 
 
Join Date: Oct 2012
Location: Anniston
Posts: 282
I did mess with the idle mixture screws a little after cleaning out the Venturi assembly. I wasn't sure how to set them though. I just tried to put them back like they were.

I'm not sure what the bell crank is. So much I'm trying to learn. I'm a total noob haha. Thanks for the suggestions. I'm planning to have a little time to look at it this afternoon.

How should I have my idle screws set?
matthewleeblair is offline  
post #12 of 15 Old 11-16-2012, 09:47 AM
davbytrace
Registered User
1979 CJ7 
 
Join Date: May 2011
Location: clinton
Posts: 487
It is the thing on the carb that the throttle cable attaches to. There should not be any play. There are two other bellcranks on your jeep. One for your clutch in the engine compartment (if a standard trans), and one for the clutch and brake pedal up under the dash. The gas pedal does not operate on a bellcrank.
davbytrace is offline  
post #13 of 15 Old 11-16-2012, 11:21 AM
Dngrs1
Registered User
1979 CJ7 
 
Join Date: May 2009
Location: Mohave Valley,AZ
Posts: 868
Yes, you can use the chem-dip for other stuff after cleaning the carb in it, as long as the carb isn't 'covered' in dirt, mud, grease, etc. Read the label on the can. When you dispose of it, it is treated as hazardous waste.

I would rather have a tool I don't need, than need a tool I don't have.
Dngrs1 is offline  
post #14 of 15 Old 11-16-2012, 04:55 PM
86cj74.2L
Web Wheeler
 
86cj74.2L's Avatar
2004 WJ 
 
Join Date: Jul 2006
Location: Stouchsburg, PA
Posts: 10,029
Here is a start.

Searching this Fourm you will find two manuals to help you in your journey. One is the FSM and one is a actual Carter repair manual.

Both are better by far then the little piece of paper in the rebuild kits.

When you dissemble the carb make sure you don't forget where the check balls go, as well as which size goes where. Make sure every hole in it is open. If your throttle shaft has play shoot me a pm. I can fix it.

Also Conceder drilling out your idle/emulsion tubes. I have a thread on drilling out the tubes as well as replacing the bushings in the baseplate.
Attached Thumbnails
image-4110104510.jpg  
86cj74.2L is offline  
post #15 of 15 Old 11-16-2012, 05:01 PM
86cj74.2L
Web Wheeler
 
86cj74.2L's Avatar
2004 WJ 
 
Join Date: Jul 2006
Location: Stouchsburg, PA
Posts: 10,029
Quote:
Originally Posted by matthewleeblair
I did mess with the idle mixture screws a little after cleaning out the Venturi assembly. I wasn't sure how to set them though. I just tried to put them back like they were.

I'm not sure what the bell crank is. So much I'm trying to learn. I'm a total noob haha. Thanks for the suggestions. I'm planning to have a little time to look at it this afternoon.

How should I have my idle screws set?
The idle mixture screw adjustment is easy. When engine is fully up to temp slowly turn in each screw 1/8 to 1/4 at a time until the idle drops. Then back them out until the idle just smooths out. If your rpm's creep up while doing it readjust your idle rpm and do the idle mixture adjustment again. Keep doing it until your know longer adjusting your idle rpm.
86cj74.2L is offline  
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.



Email Address:
OR

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.




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



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