BBD adjusting after rebuild and other upgrades

**twoleos617** · 04-23-2009, 10:51 AM

I've Nuttered, T.R.'d, and valve cover gasket replaced lately. I've read many threads including this one... http://www.jeepforum.com/forum/f8/1986-cj7-2-5-litre-tailpipe-backfiring-447008/?highlight=carb+adjust

I have a pic i need a question answered on. what are the adjustments on these screws? are they the diesling screws? The one on right seems to control the level on the plastic flap in front of it but that flap stays in one position no matter where the screw is adjusted to.
http://s692.photobucket.com/albums/vv281/twoleos617/Carb%20rebuild%20after/?action=view&current=carbadj.jpg

I've adjusted the screws on the front of the carb as per the Nutter directions.
I'm getting continous popping/sputtering from the tailpipe upon decel at any speed. Also, getting hard cold starts now. seems as though my electric choke is not working properly. it used to idle at 2k when cold and stayed there until i kicked it down after warming up.

**Mike Romain** · 04-23-2009, 11:10 AM

You should have gotten the kit for $20.00. It comes with a new accelerator pump and float needle and seat as well as great directions on how to set up the carb. The Haynes CJ manual also has great directions.

What nutter directions did you use?

Where did you set the stepper motor's air pins at?

Those screws in the photo are the idle screw and the fast idle screw.

You also appear to be missing the accelerator pump connecting rod and the fast idle cam connecting rod. They go on the left in the photo. And on the right, you are missing the choke connecting rod. OK, that is what the choke is stuck open... It won't start nor run well that way...

To set the fast idle, you warm up the engine and put the plastic cam so the screw hits on the second from the top step. You then adjust the screw until you get 1750 rpm I think it is. This gives you back the cold fast idle when the choke is closed.

The other screw just adjusts the base rpm when the engine is warmed up.

**twoleos617** · 04-23-2009, 12:21 PM

I got the $15 kit from AZ. I thought it had everything I needed. I'll go back through the instructions and Haynes. it came with float needle and seat but the accelerator pump im a little ingnorant on.

I used the Nutter here on JF
http://www.jeepforum.com/forum/f8/how-nutter-bypass-522262/?highlight=nutter

i used the idle mixture screws to adjust the pins. i set them at 4.5 turns out i think. i'll search and double check that setting.

i did reinstall the accelerator pump connecting rod and the fast idle cam connecting rod but after i took the pics.

i'll set the fast idle and base idle screws as per you instruction. i appreciate the help. i think i just about have this whole personal "carb mystery" figured out. this experience is what i needed to get to know how things work.
you've been a big help. thanks.

**Mike Romain** · 04-23-2009, 12:35 PM

The stepper pins need to be set with their shoulder about 1/8" from the back wall or about in the middle of their travel. (Red arrow) You can take off the motor (blue arrow) and move the backing plate in steps until it just fits into the motor's case. When you put the motor back in, the pins should then be right.

After you have those pins set, then reset the mix down front, the screws should be in more usually to get the best lean idle mix.

Oh, it will burble and pop a 'little' when you decelerate, you have the timing fixed at about 9 deg now right and the computer isn't adjusting it any more.

**twoleos617** · 04-23-2009, 01:02 PM

i will check those pins tonight and adjust acordingly. i have everything else you mentioned above set as instructed. i'll recheck all screws front and back after setting the pins too.
I used a timing light to set at 8-9* BTDC.
right now im idleing at 700-800 rpm when warm. i'll listen to burbling on my way home and see how she starts in the morning after your sugesstions. i'll post up with my results in the a.m.

**twoleos617** · 04-24-2009, 07:31 AM

Mike,
made the changes and she fired right up first time. it wasnt as cold as it has been the past few mornings but never-the-less shes running well. upon start up, she instantly idled at 800rpm. i'll have to go over my choke setting b/c i thought it would idle higher until the engine hit N.O.T. maybe it was just the outside temp that didnt pull the idle up but im not complaining. still had some sputtering in the exhaust but if thats to be expected then im certainly ok with that...kinda like the way it sounds anyway! thx for your help...yet again!!