Holley 470 Truck Avenger fast idle

[malcolmzilla]

After several attempts to adjust the screw, and removing the carb twice, I still cannot get my 470 TA to fast idle on a cold start.

Can some one confirm the fast idle cam operation for me? It appears that the choke arm that closes the flapper pulls a plastic cam up and thus bumps the spring loaded idle arm (with adjustable screw) into place which catches on a second arm and rotates the main throttle a bit and picks up the idle. A tap on the accelerator bumps the cam to a deep detent and releases the fast idle arm.

After removal and inspection, it appeared that my previous attempts to turn the fast idle screw in (and isn't that easy to get at huh?) had bent the idle arm out so it didn't catch the main throttle plate armature so I backed it out and bent the arm back to catch. Still no fast idle.

Then I thought perhaps I had too much return spring preventing the fast idle spring from moving the main shaft, so I put a softer one on, still no fast idle.

So then I watched the choke and it does fully close the flapper and bump the red cam (out of box setting) so I can't figure WTF the problem is.

Thanks for any tips, or sympathy.

 

[ugly_od_eb]

I got a 670 TA and had the oppisite problem... too high of an idle, i adjusted it by loosing the black cap and rotating it until i was happy with it. Hope this helps

 

[oleguy74]

choke does not move throtle shaft.all it does is operate fast idle cam.when you push throtle down choke closes fron spring tenison from the black choke part.go to holley performance product search.click on holley performance product search.your part # shoud be 0-90470. you can print out all info.save the site to your bookmarks .

 

[broncnaz]

You've got the operation right. Might need to turn the screw in more to catch the step plate also make sure your choke is closing it might need to be adjusted also in warmer weather it may not fully close because its not needed.

 

[malcolmzilla]

Thanks guys, guess I'll keep messing with it...