1985 chevy 305 problems starting

[2dooreighty5]

hey guys, so i have a 1985 caprice with the 305 and recently sprayed the carb with carb cleaner because i saw some dirt build up and wanted to clean it off. A day or two later i noticed that when i would go out in the morning to start it, the car would run like crap...smokes out the tail pipes and sounds like its running either way to lean or way too rich...if i hold the pedal down it still runs like crap but after about a minute it will smooth out and eventually come to the high idle and then back down to normal idle rpms. Im just trying to figure out why at start up its doing that and if maybe it has something to do with cleaning the carb....thats all ive done in last month and before that it was starting fine...the only way i can describe the shitty start up is as if it has way too much gas in the carb or none at all because the whole car shakes and its ideling super rough....any ideas guys??????

[j cAT]

spraying carb cleaner on the carb you must be very careful not to get the rubber destroying cleaner in the choke pull off''s.. these control the cold start choke opening and prevent secondaries from opening when cold. also when these leak you now have vacuum leaks. with a vacuum guage you can check if the internal diaphram is ruptured.

with vac applied these devices should quickly move inward.

the other rubber would be the hoses connected to the carb. these also get damaged.

carb cleaner is only for metal , rubber is destroyed by this product.

[j cAT]

use electronic contact cleaner or minerial spirits paint thinner , to clean the exterior of the carb from oils and dirt. I use low odor minerial spirits to clean parts with rubber and metals with a small brush etc..

[2dooreighty5]

thanks for reply's guys...so do i need to pull the whole carb off and re do the cold start choke rubber...or can i maybe just pull top half of carb off...by the way its a quadrajet...

[j cAT]

Originally Posted by 2dooreighty5

thanks for reply's guys...so do i need to pull the whole carb off and re do the cold start choke rubber...or can i maybe just pull top half of carb off...by the way its a quadrajet...

the choke pull off is mounted on the side of the carb. you replace the whole totally sealed choke pull off.

the mounting is by some screws, disconnect the vac hose.

you do not take take the carb appart or off the engine.

[j cAT]

Originally Posted by 2dooreighty5

thanks for reply's guys...so do i need to pull the whole carb off and re do the cold start choke rubber...or can i maybe just pull top half of carb off...by the way its a quadrajet...

this maybe what you need , this as you can see has 2 mounting holes. this may be exactly the one you need. cost is usually about 25.oo..

check it out http://www.ebay.com/itm/PRIMARY-CHOK...88c677&vxp=mtr

[2dooreighty5]

im pretty sure thats not what i need...that thing is metal like u said...and im pretty sure i didnt spray that with the carb cleaner...i mainly sprayed ontop and into the carb... the car will run for the standard 60 to 120 second and then kick down to low idle, but its just that first minute it runs like crap...Im gonnna have some time this afternoon to check it out...if you have any ideas please dont hesistate guys

[j cAT]

Originally Posted by 2dooreighty5

im pretty sure thats not what i need...that thing is metal like u said...and im pretty sure i didnt spray that with the carb cleaner...i mainly sprayed ontop and into the carb... the car will run for the standard 60 to 120 second and then kick down to low idle, but its just that first minute it runs like crap...Im gonnna have some time this afternoon to check it out...if you have any ideas please dont hesistate guys

that thing is metal on the outside ! that thing controls the fuel mixture to the engine on a cold start.

INSIDE IS A RUBBER DIAPHRAM THAT WITH JUST A SMALL AMOUNT OF CARB CLEANER CAUSES IT TO GET DESTROYED.

PLACE VACUUM ON THAT THING, SEE IF IT MOVES LIKE A MOUSE TRAP. IF it moves slowly /or not at all , it is leaking.

[2dooreighty5]

forsure! thanks for your help man...we will see tomrrow morning...im pretty sure that is the problem because when i manualy pulled that thing in so it wasnt touching the throttle linkage it started fine...so tomrrow on cold start ill see where its at....I aslo have a question about this filter tube thing that sits out infront of the carb which runs to pvc valve and off the carb in 3 places...i wanna eliminate it cuz i dont have any emmisions stuff on the car....ill try to post a photo of it....and ill update on the carb tomrrow

[j cAT]

Originally Posted by 2dooreighty5

forsure! thanks for your help man...we will see tomrrow morning...im pretty sure that is the problem because when i manualy pulled that thing in so it wasnt touching the throttle linkage it started fine...so tomrrow on cold start ill see where its at....I aslo have a question about this filter tube thing that sits out infront of the carb which runs to pvc valve and off the carb in 3 places...i wanna eliminate it cuz i dont have any emmisions stuff on the car....ill try to post a photo of it....and ill update on the carb tomrrow

in front of the carb is a plastic case with a few hoses connected to it. this is part of the fuel evap system. there is a valve inside this which does rupture . then fuel gets sucked into the carb , which is not good.

I would find a replacement rather than try to bypass this. you may find that the vehicle may create fuel odors.

[2dooreighty5]

Ya I figured it was emissions stuff I just figured since I'm done and have everything else related to emissions pulled off the car I could by pass that thing too... But if it has a purpose maybe I'll just leave it...

Update on carb problem: it's nt doing it anymore!!! All I did was mess with the cold start thing and pressed it in or something and now it starts fine even kicks down to low idol nicely... Pretty funny actually

[j cAT]

Originally Posted by 2dooreighty5

Ya I figured it was emissions stuff I just figured since I'm done and have everything else related to emissions pulled off the car I could by pass that thing too... But if it has a purpose maybe I'll just leave it...

Update on carb problem: it's nt doing it anymore!!! All I did was mess with the cold start thing and pressed it in or something and now it starts fine even kicks down to low idol nicely... Pretty funny actually

could be the cold start high speed cam got stuck. this is steel that does get rusty when it ages. then it can stick. if it does the choke will not close fully on a cold start.