I was reading the manual and the only way they tell me to adjust this is to use an exhaust gas spectrum analyzer thingy or something which I dont have. When I fist did work on the carb I only found the mixture screw, not the idle screw so I just fiddled with that and it really helped the engine and I got it running 100% better after I messed with it and the timing. Now I have found the idle speed screw and re-adjusted everything that it tells me to in the maual and it runs even better. But now the engine seems to "stumble" while its dropping in RPM's (after I rev it up and let it come back to an idle). I tried putting the mixture screw back where it was before I started because I didnt have this problem before I messed with it, but the car wont run with it there now !?!?!? So I was just wondering how far out you take your mixture screws for average performance with no mods.

~T.J.

 

did u rebuild the carb., my air/fuel mix is out 3 turns, also adj the idle to 950 rpms, now i dont worry about the rpms falling ,,,http://pittdp.homestead.com/underhood.html

 

No, I did not rebuild the carb. Plus my car idles beautifully at the manuals reccomended 750 RPM's. It also reves up with 100% better throttle respose (no more putting you foot through the radiator to get 4K RPM's, yes, it was that bad). My problem comes when it drops from being revved to an idle, then it kind of stumbles, but it never did it before I messed with anything... Of course before I messed with anything it was barely running and idleing at about 1500 RPM's and missing constantly. The timing was so far off and there were two vaccum lines disconnected and one big one with a hole in it...After all that fixed I still have just one problem that bothers me, but i guess thats what i get for being a perfectionist. Ill try moving the mixture screw and see if that helps.

~T.J.

 

there is a tps that u can adjust,,between the carb and t-stat housing, on block ,make sure all the wires are snug that control it,,i tweeked mine clockwise about 1 turn, also on the fuel return line from carb u might want to check the little metal looking fuel check valve, mine was clogged, there kinda like a pcv valve i guess,,,,,,,and they go on just one way when u reinstall it,,,,

 

how was it acting , for you to mess with air/fuel, idle screws,,rough ??
like on only one rotor ? if so,,check the decel.valve,, (coasting)valve
there are so many valve's, actuators, elect. connectors,on these carbs
not to mention just the vacum lines,it could drive a person nuts trying
to zero some of those symptons

 

Trust Me...I Know...

~T.J.

 

so whats the problem ? car still don't run right after rebuilding the carb??i'll trust you,,so what do you know ?? get-it ??just trying to help,,
i just went through the same,,i fixed mine first time,,without a rebuild.
car runs perfect

 

Don't use the Haynes proceedure to adjust the mixture or idle on a 1981 or newer.. They were written using a 1979.

Search for my name and "Mixture" or "Idle" and you'll find the proceedure.. Too long to retype. I'll search later and cut n paste if you can't find it... It's been a while.