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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: DouglasBeale on November 11, 2018, 06:02:58 PM

Title: Carburetor not idling down after emissions delete - choke pull off vacuum hose?
Post by: DouglasBeale on November 11, 2018, 06:02:58 PM
(https://photos.google.com/photo/AF1QipObd9r2qe7Ldb-PQc_zvKM8MyGq_E6jMW9oJDmf)

Should my choke pull off vac hose be going to carburetor or manifold? As you can see it's going to the carburetor, but the carburetor isn't idling down. When I remove the line going to choke pull off, and rev it, it'll idle down. The bottom line off the manifold goes to the carburetor just below the choke, the top hose goes to distributor.  Second picture shows the hose that goes to the choke pull off from the other side. 

I think I got something mixed up doing the emissions delete.



Backside port is plugged

Title: Re: Carburetor not idling down after emissions delete - choke pull off vacuum hose?
Post by: Rapid Roy on November 11, 2018, 08:48:46 PM
WOW...If there are suppose to be pics, then, none seen.
Title: Re: Carburetor not idling down after emissions delete - choke pull off vacuum hose?
Post by: DouglasBeale on November 12, 2018, 06:05:31 AM
WOW...If there are suppose to be pics, then, none seen.

I see the pictures??? Anyone else cant see them?
Title: Re: Carburetor not idling down after emissions delete - choke pull off vacuum hose?
Post by: VileZambonie on November 12, 2018, 07:13:31 AM
no pics
Title: Re: Carburetor not idling down after emissions delete - choke pull off vacuum hose?
Post by: DouglasBeale on November 12, 2018, 05:20:56 PM
Sure hate to have to paint it :)
Title: Re: Carburetor not idling down after emissions delete - choke pull off vacuum hose?
Post by: DouglasBeale on November 12, 2018, 05:52:30 PM
Can you guys see those pics now?
Title: Re: Carburetor not idling down after emissions delete - choke pull off vacuum hose?
Post by: DouglasBeale on November 12, 2018, 07:26:51 PM
I spent some time working on the carb today. ?The kid I bought this truck from said he rebuilt the carburetor?

That vacuum can must be hooked up correctly because it seems to be functioning properly. 

I adjusted the choke and it starts better, although not perfectly.  The choke is electric assets, is getting 14v, and it opens pretty quickly, but I still dont think its idling down correctly.

I also backed off on the "fast idle" screw and everything seems a little better, but I still smell fuel or a rich exhaust I guess???...

On the drivers side - If I push the throttle forward It kind of clicks, (it's touching that little can with the bolt) then it's idling down very nicely.. It sounds like a new car.

+++++++++++Another issue ++++++++++

The little linkage thing that hangs down behind the choke, (it prevents the secondary throttle blade shaft from opening - like a hold closed thing). That thing should back off with the choke, but it doesn't, and I don't think the secondaries are kicking in at all. The only way I can get 4 barrels to fire is to push that thing back with my finger, then I can throttle up and and the secondaries open right up and I can hear it scream. I never hear it when I'm driving so I'm not sure if they open at all. Secondaries are very stiff. The top doors open fine, but the blades seem real stiff just from what I can feel working them by hand.   

I did order a vacuum tester gauge and the carburetor adjusting tool so I can adjust mixture screws too.

One more thing: The basic Idle screw does not touch the linkage at all - It's backed all the way out. 

Title: Re: Carburetor not idling down after emissions delete - choke pull off vacuum hose?
Post by: VileZambonie on November 13, 2018, 04:23:56 AM
This easily explains and shows the secondary lockout. Now if it's not coming off of the fast idle cam and the choke lever isn't fully opening it will not allow the secondaries to open.

https://www.youtube.com/watch?v=_mwX06-3LV8
Title: Re: Carburetor not idling down after emissions delete - choke pull off vacuum hose?
Post by: DouglasBeale on November 14, 2018, 03:03:52 AM
Now if it's not coming off of the fast idle cam and the choke lever isn't fully opening it will not allow the secondaries to open.

Thanks Vile, It looks to me as is the choke is fully open. I'll get a little mirror today and see if I can get a better look behind the choke. Maybe I'll pull the choke off, but that lockout is all willy nilly and definitely not backing off (also not gaped). It doesn't feel like anything is connected to anything, but I'll check it out.

BTW: I don't have that damper assembly on mine???