Author Topic: Just a quick question about idle....  (Read 1416 times)

Offline 1979C20

  • Senior Member
  • ****
  • Posts: 1659
  • Kyle Taulton.
Just a quick question about idle....
« on: January 17, 2011, 09:54:41 PM »
So, I adjusted my carb and timing then my idle, set it at about 650 or 700. Then, just recently, my idle randomly lowered down to like 450 or 500. Its stayed at the lower for the past 3 days, without me adjusting anything. What would change it to randomly lower itself? I'm happy with it there. Just curious as to why? Would colder temp do it? Because its been down in the 60's or so. But today it was like 80 and it was still low.
1979 SCLB C20 Q-jet 350 SM465 14b F.F. 4.10 G80
1989 GMC Suburban V2500 TBI350 TH400 4in lift 35's 14b SF

Offline MITOYZ

  • Newbie
  • Posts: 15
Re: Just a quick question about idle....
« Reply #1 on: January 21, 2011, 06:51:21 PM »
was the motor cold or warm when you adjusted it, good chance that when you adjusted it the carb was at fast idle. There's a little cam on the throttle linkage that will hold it on fast idle. Might want to reset it, but before you do, let it run for 10 minutes, then bump the throttle, then adjust your idle

Offline 1979C20

  • Senior Member
  • ****
  • Posts: 1659
  • Kyle Taulton.
Re: Just a quick question about idle....
« Reply #2 on: January 21, 2011, 07:00:51 PM »
It was at running temp, because i set the timing and idle. It was at about 700 for about a month. then it dropped to 500ish.
1979 SCLB C20 Q-jet 350 SM465 14b F.F. 4.10 G80
1989 GMC Suburban V2500 TBI350 TH400 4in lift 35's 14b SF

Offline MITOYZ

  • Newbie
  • Posts: 15
Re: Just a quick question about idle....
« Reply #3 on: January 21, 2011, 07:09:14 PM »
wonder if it had a carbon build up inside the carb at the throttle blades, holding it open a little