At 03:35 AM 7/3/2015, SDF ( aka ;jim lahey' - Scott ) wrote:
>try this ..
>it's 'cheating' but 'might' get you the result you need.
>
>What I've found is even when the allen screw loosens properly, and the
>eccentric adjusting feature works..
>sometimes..
>it still won't adjust to the correct setting.  I aim for contact at
>closed throttle and it uncontacting 'just off' idle.

It runs into two problems -- cam wear to some slight extent maybe,
and the throttle plate shaft wandering around as the throttle body
wears.  On a new one you can set it by the book.  On a worn one you
may have to adjust as you mention below and you also may have to set
it with vacuum applied to the throttle body either by running engine
or a shop vac.  You may alsow have to allow for the throttle cable
not *quite* returning to zero in cold weather when released gently.

>I've had to bend the little metal tab thingey that the cam pushes on.
>Like with a needle nose pliers.

That's the operating arm of the switch.  It presses on the little
button/shaft that actually enters the switch and moves the element so
that it snaps from one configuration to the other.  It (the
Microswitch-type switch) is a design of genius, with a stressed
moving contact that holds on to its existing shape until it's pushed
noticeably past center, then abruptly snaps into the other shape.  It
has built-in hysteresis, extremely rapid switching action and stable
and precise actuating points.  On this switch it's operated by that
little lever which is pivoted on little holes in the switch body.  Be
careful not to overstress them when bending the lever.

John's big problem right now is the little adjusting cam has lost its
means of holding on to a hex key, so he has to remove that cam
entirely and move the adjusting plate by hand.   And I forgot to tell
him he might have to bend the switch lever as you said.

Yrs,
d