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-   -   Need help with fast idle cam not working (https://67-72chevytrucks.com/vboard/showthread.php?t=812509)

OUbesto 09-27-2020 07:54 AM

Need help with fast idle cam not working
 
I have a Holley 4 bbl model #1850-3 with electronic choke on my '70 C-10 BB. The choke works perfect. However, the fast idle does not kick in when the engine is cold. I Have adjusted the fast idle adjustment screw in both directions (in and out) but it does not change the RPM. Should I be able to slightly rotate the cam by hand when I first cold start the engine and force an increase in RPM?

Any thoughts? Suggestions?

geezer#99 09-27-2020 09:09 AM

Re: Need help with fast idle cam not working
 
Has it been apart?
Try marking the cap position and then rotate it full rich to see if it goes on the high idle step up cam.

OUbesto 09-27-2020 06:20 PM

Re: Need help with fast idle cam not working
 
Quote:

Originally Posted by geezer#99 (Post 8814334)
Has it been apart?
Try marking the cap position and then rotate it full rich to see if it goes on the high idle step up cam.

I'll try your suggestion this weekend.

I did have a local guy rebuild it and it hasn't worked since. I just had it back to him and he said it appeared to be engaging properly but since I drove it there, the engine was too hot to test. The next morning the fast idle did not kick in. Of course when I drove over to his shop Sat morning, he is gone for a week! :devil:

RustyPile 09-27-2020 07:07 PM

Re: Need help with fast idle cam not working
 
The fast idle cannot be accurately adjusted once the choke is fully open as the fast idle cam has fully "retracted".. Here is a link to making preliminary fast idle adjustments.. The procedure will get you pretty close to the correct cold engine fast idle speed..

https://youtu.be/4BTiXcMHdXM


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