baffling carburator ajustments...

[Mac]

well, i tried ajusting the "air bleed screw" as mentioned in an earlier post:
viewtopic.php?t=2361

all it seemed to do was make the car stutter again (skip a beat when idling, it didn't do this prior to ajustment) and change the idle, and no matter what direction i tuned the screw engine vacuum remained the same.

I figured i got it right, so then i tried to ajust the idle speed with the screw, then the throttle positioning screw got in the way and i couldn't turn it down enough. it was still stuttering and it was still idling too high.

fed up and tired, i turned the air bleed screw in all the way, unscrewed it roughly 2-3 turns, set the idle speed, put the throttle ajustment screw back to its origional position and took it for a spin. it seems faster, it still stutters, just not as much and it makes alot of intake noise now at WOT.

anyways, i'm hoping someone here knows how to set it properly as the chilton's manual is next to useless. sorry for the unarticulate post, but i'm feeling pretty sleepy and annoyed at the tercel right now.

[waynehoc]

I use the procedure in the FSM on pages FU-28 thru FU-30 which is based on rpm vs vaccuum. I believe this is known as the 'lean drop' method. Didn't have to drill out the (idle) mixture adjusting screw (MAS) plug as was already done. The MAS is what I believe thebigbread is referring to as the 'air bleed screw'. Page FU-4 gives a pretty good idea of what you are doing when adjusting the idle mixture screw.

I found I could adjust it to 650rpm okay by the method in the FSM, but as a last adjustment had to adjust the idle speed screw up a wee bit to about 750 to 800rpm for practical functioning such as running with lights on, brake lights on at stop signs, heater motor running, etc.

On page FU-25 are listed the 'Initial Conditions' required for setting the idle mixture.

[Typrus]

Don't you have a Weber, Mac?
If so, there are tons of adustment things online.

Mine has stuttered as long as I can remember. I always thought it was a weak dist.

[thebigbread]

well, i tried ajusting the "air bleed screw" as mentioned in an earlier post:
viewtopic.php?t=2361

all it seemed to do was make the car stutter again (skip a beat when idling, it didn't do this prior to ajustment) and change the idle, and no matter what direction i tuned the screw engine vacuum remained the same.

I figured i got it right, so then i tried to ajust the idle speed with the screw, then the throttle positioning screw got in the way and i couldn't turn it down enough. it was still stuttering and it was still idling too high.

fed up and tired, i turned the air bleed screw in all the way, unscrewed it roughly 2-3 turns, set the idle speed, put the throttle ajustment screw back to its origional position and took it for a spin. it seems faster, it still stutters, just not as much and it makes alot of intake noise now at WOT.

anyways, i'm hoping someone here knows how to set it properly as the chilton's manual is next to useless. sorry for the unarticulate post, but i'm feeling pretty sleepy and annoyed at the tercel right now.

hmm.. sorry bout that, if the tercel is running fine i would not recommend doing my procedure. my 3ac is in rough condition and running on 2 year old (stale) gas, & was dying constantly at stock settings.

BUT typrus is right, if u have a weber, its probably not best to use my procedure, as i have always had the stock carb.

oops.. i see you have a 4ac as mentioned in you sig, that is probably also the reason it stutters.

edit:
about the intake noise, mine sounds like a souped-up 4AGE taking off on the 1/4 mile

[Mac]

webber is on the "to-do" right now, my experiance isn't first hand per se, I had a friend with webbers on his VW bug in highschool, thuroughly impressive. also, the fact that the stock carb is so finicky is why i think highly of webbers.

waynehoc, would it be possible for you to scan those pages of the FSM? i only have the chiltons manual which dosn't list anything specifically for the 3A/4A-C

[waynehoc]

Mac, all the page references are from the 1985 FSM which is downloadable from the tercel4wd home page here http://tercel4wd.com/ Just click on 'Technical Info' and download away...

[Typrus]

You should see my instructors bug collection... All have at least Weber 32/36's. One has I think a 48mm IDF or something like that. Hes planning a quad-downdraft. Its interesting for sure.