2150 Carb Adjustment

[Dan]

You know those two screws at the base of the carb facing forward? My Chilton basically just says not to mess with them, but there is a Tech Library article on this site that says that you can fully seat the screws, then back them out about 7/8 of a turn (for an AMC360) and that will be about the right adjustment. Anyone have any comments about that?

[DerJeep]

Dan,

Backing the mixture screws out 7/8 of a turn is just a starting point. Not every application will be the same either.

I got excellent results using the vacuum gauge method described at this site: http://www.centuryperformance.com/vacuum.htm

My Wag ran great after doing it, but still narrowly failed the smog test. Had to have it hooked to a sniffer and fine-tuned to pass. Needless to say, it ran a little worse after getting to pass.

If you do not have to go through an emissions test, then the methode described on the site will set you pretty straight.

[wagdriver]

These are idle mixture screws and when our rigs were manufactured they were set at the factory for a condition called lean best idle. They normally would not need any adjustment in a perfect world. If you have rebuilt the carb or done some other work you may have to readjust the idle mixture. When you turn the screws in fully you shut of gas to that venturie for the idle circuit in the carb. Turning them out after seating determines the idle mixture. The 7/8 turn is a ball park starting point for first adjustment, and in a lot of cases works without any futher adjustment.
I have always been instructed to set them to this initial setting and start the engine. Slowly turn them one at a time in until the engines stumbles, then back them out until you obtain the highest idle speed. Then readjust the idle speed until you get the desired rpm for our rigs which is 500 rpms +/- 50 with the solenoid disconnected. This is called base idle. After that adjustment is made then you reattach the solenoid blip the throttle to let it extend and adjust the idle speed with it to 600 rpms +/- 50. This is curb idle. May be one of the other guys has a better way but that is the how I do mine ;)
Well I see that some one does have a better way. We all learn things on this board Thank you for the info. smile.gif

[ December 06, 2001: Message edited by: wagdriver ]

[Dan]

Thanks to you both for the info, and the link to the website. And since our wrestling governor Jesse the Body got elected, we've done away with all emissions testing.

I guess I'll do my best to cope with the 2150 until my wife lets me buy the EFI setup smile.gif .

Oh yeah, one other thing. Does that mean that turning the screws in makes it run leaner?

[ December 06, 2001: Message edited by: Dan ]

[reddog]

Oh yeah, one other thing. Does that mean that turning the screws in makes it run leaner?


Yes, leaner. I would suggest that when you turn the screws in to count how many turns it takes so you know where you started from and not to tighten the screws down hard. Snug is more than enough

Kerry